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1.
J Environ Manage ; 323: 116252, 2022 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-36126600

RESUMO

Bacillus as a predominant genus of enzyme-producing bacteria presents desirable features to fulfill the vast demand of specific industries, whereas the knowledge of the Bacillus communities and their capacities of producing industrial hydrolytic enzymes across the microhabitats of the Paracel Islands is limited. Herein, a total of 193 culturable Bacillus strains belonging to 19 species were isolated across the microhabitats of seawater, sediment, coral and seagrass, covering 39 stations of the Paracel Islands. Each microhabitat displayed its unique species, while the species of Bacillus paramycoides besides being the dominant species with an abundance of 54.94% also was the only species shared by all microhabitats of the Paracel Islands. Of the Bacillus communities, 97.41% of the isolates exhibited the capacity of producing one-or-more types of enzymes with comparatively higher and broader ranges of enzyme activities, including 163 protease-, 27 cellulase-, 118 alginate lyase-, 140 K-carrageenase- and 158 agarose-producing strains. By the correlation analyses of "Bacillus-environmental factors" and "Enzyme-producing Bacillus-environmental factors", the cross-habitat distribution and enzyme-producing capacity pattern of the Bacillus communities were strongly driven by habitat type, and the environmental factors made habitat-dependent differential contributions to that in the Paracel Islands. It's worth noting that the cellulase-producing strain wasn't detected in seagrass due to its survival strategy to prevent cellulose degradation by inhibiting cellulase-producing bacteria, while coral contained more stable microbial metabolic functions to protect against environmental fluctuations. These findings besides providing large quantities of promising enzyme-producing candidates for specific industrial desires, also facilitate the development and utilization of marine microbial resources and the environmental policy- and/or law-making according to environmental features across the microhabitats of the Paracel Islands.

2.
Environ Sci Technol ; 2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36099335

RESUMO

Arsenic (As) is toxic and ubiquitous in the environment, posing a growing threat to human health. As-hyperaccumulator Pteris vittata has been used for phytoremediation of As-contaminated soil. Symbiosis with arbuscular mycorrhizal fungi (AMF) enhances As accumulation by P. vittata, which is different from As inhibition in typical plants. In this study, P. vittata seedlings inoculated with or without AMF were cultivated in As-contaminated soils for 2 months. AMF-root symbiosis enhanced plant growth, with 64.5% greater As contents in the fronds. After exposure to AsV for 2 h, the arsenate (AsV) and arsenite (AsIII) contents in AMF-roots increased by 1.8- and 3.6-fold, suggesting more efficient As uptake by P. vittata with AMF-roots. Plants take up and transport AsV via phosphate transporters (Phts). Here, for the first time, we identified a novel mycorrhiza-specific Pht transporter, PvPht1;6, from P. vittata. The transcripts of PvPht1;6 were strongly induced in AMF-roots, which were localized to the plasma membrane of arbuscule-containing cells. By complementing a yeast mutant lacking 5-Phts, we confirmed PvPht1;6's transport activity for both P and AsV. In contrast to typical AMF-inducible phosphate transporter LePT4 from tomato, PvPht1;6 showed greater AsV transport capacity. The results suggest that PvPht1;6 is probably critical for AsV transport at the periarbuscular membrane of P. vittata root cells, revealing the underlying mechanism of efficient As accumulation in P. vittata with AMF-roots.

3.
BMC Psychiatry ; 22(1): 612, 2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36114485

RESUMO

BACKGROUND: In recent years, the rates of suicide among young people have been increasing, and major depressive disorder (MDD) is regarded to be its main cause. Many factors such as thyroid dysfunction and metabolic abnormalities are thought to mediate this process, but the conclusions are inconsistent. This study investigated the rate of suicide attempts and associated risk factors among young, first-episode and drug-naïve Chinese Han patients with MDD. METHODS: A total of 917 patients with MDD (aged 18 ~ 35 years) were recruited. Demographic and clinical data were collected and thyroid function, fasting blood glucose and lipid profiles were measured. The Hamilton Depression Rating Scale-17 items (HAMD-17), Hamilton Anxiety Rating Scale (HAMA), positive symptom subscale of Positive and Negative Syndrome Scale (PANSS) and clinical global impression of severity scale (CGI-S) were adopted to assess depression, anxiety, psychotic symptoms and disease severity respectively. RESULTS: The rate of suicide attempts was 19.5% in young MDD patients. There were significant differences in age (p = 0.003), education level (p = 0.001), age of onset (p = 0.004) and disease duration (p = 0.001) between patients with and without suicide attempts. Compared with patients without suicide attempts, patients with suicide attempts had significantly higher scores on the HAMD-17, HAMA, PANSS positive symptom subscale and CGI-S (all p < 0.001). Patients with suicide attempts had significantly higher levels of TSH (p < 0.001), TgAb (p = 0.004), TPOAb (p < 0.001), TG (p = 0.016), TC (p < 0.001), LDL (p < 0.001), and fasting glucose (p < 0.001), but significantly lower levels of HDL (p < 0.001). Logistic regression analysis showed that marital status (OR = 0.515, 95%CI: 0.280-0.950, p = 0.515), disease duration (OR = 1.100, 95%CI: 1.013-1.194, p = 0.024), HAMA score (OR = 1.313, 95%CI: 1.205-1.430, p < 0.001), CGI-S score (OR = 1.875, 95%CI: 1.339-2.624, p < 0.001), levels of FT3(OR = 0.717, 95%CI: 0.536-0.959, p = 0.025), TPOAb (OR = 1.004, 95%CI: 1.002-1.006, p < 0.001), TC (OR = 1.330, 95%CI: 1.011-1.750, p = 0.042) and LDL (OR = 0.736, 95%CI: 0.558-0.971, p = 0.030) were all independently associated with suicide attempts in young MDD patients. CONCLUSIONS: In China, the rate of suicide attempts in young patients with MDD is quite high and thyroid dysfunction and metabolic abnormalities may be implicated in its pathogenesis.


Assuntos
Transtorno Depressivo Maior , Tentativa de Suicídio , Adolescente , Glicemia , China , Humanos , Lipídeos , Fatores de Risco , Tireotropina
4.
Exp Hematol Oncol ; 11(1): 57, 2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36114573

RESUMO

The combination of rituximab, lenalidomide, and Bruton's tyrosine kinase inhibitor (BTKi) ibrutinib, followed by chemotherapy, has shown high efficacy in patients with newly diagnosed diffuse large B-cell lymphoma (DLBCL) in Smart Start trial. We aimed to evaluate the efficacy, safety of SMART (rituximab + lenalidomide + BTKi) regimen and SMART-START regimen as a first-line treatment in elderly or unfit DLBCL patients. 31 patients were included, 17 used SMART regimen, with median age 82 years, 14 unfit patients received SMART-START regimen. 14/16 (87.5%) patients in SMART group achieved overall response (OR), with 10/16 (62.5%) achieved complete response (CR). 12/13 (92.3%) patients in SMART-START group achieved OR, with 8/13 (61.5%) achieved CR. With a median follow-up of 15.4 (3-29.1) months, median progression-free survival (PFS) and overall survival (OS) have not been reached, 1-year PFS was 81% in SMART group and 84% in SMART-START group. Common grade 3-4 adverse events (AEs) during SMART regimen were neutropenia (8 [25.8%]), infection (6 [19.4%]) and skin rash (3 [9.7%]). Our study shows that SMART regimen is an effective and safe therapy for elderly DLBCL patients, and SMART-START regimen can be used in unfit patients who could not tolerate intensive chemotherapy in the onset.

5.
Stem Cell Res Ther ; 13(1): 449, 2022 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-36064647

RESUMO

BACKGROUND: Increasing studies have reported the therapeutic effect of mesenchymal stem cell (MSC)-derived exosomes by which protein and miRNA are clearly characterized. However, the proteomics and miRNA profiles of exosomes derived from human embryonic stem cells (hESCs) and human-induced pluripotent stem cells (hiPSCs) remain unclear. METHODS: In this study, we isolated exosomes from hESCs, hiPSCs, and human umbilical cord mesenchymal stem cells (hUC-MSCs) via classic ultracentrifugation and a 0.22-µm filter, followed by the conservative identification. Tandem mass tag labeling and label-free relative peptide quantification together defined their proteomics. High-throughput sequencing was performed to determine miRNA profiles. Then, we conducted a bioinformatics analysis to identify the dominant biological processes and pathways modulated by exosome cargos. Finally, the western blot and RT-qPCR were performed to detect the actual loads of proteins and miRNAs in three types of exosomes. RESULTS: Based on our study, the cargos from three types of exosomes contribute to sophisticated biological processes. In comparison, hESC exosomes (hESC-Exos) were superior in regulating development, metabolism, and anti-aging, and hiPSC exosomes (hiPSC-Exos) had similar biological functions as hESC-Exos, whereas hUC-MSCs exosomes (hUC-MSC-Exos) contributed more to immune regulation. CONCLUSIONS: The data presented in our study help define the protein and miRNA landscapes of three exosomes, predict their biological functions via systematic and comprehensive network analysis at the system level, and reveal their respective potential applications in different fields so as to optimize exosome selection in preclinical and clinical trials.


Assuntos
Exossomos , Células-Tronco Pluripotentes Induzidas , Células-Tronco Mesenquimais , MicroRNAs , Exossomos/genética , Exossomos/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Proteômica , Cordão Umbilical
6.
Artigo em Inglês | MEDLINE | ID: mdl-36127506

RESUMO

The factors associated with suicide attempts in major depressive disorder (MDD) patients with comorbid glucose disturbances remain unclear. To the best of our knowledge, this is the first study with a large sample size to examine risk factors of suicide attempts in first-episode drug-naïve (FEDN) MDD patients with comorbid glucose disturbances, including clinically relevant factors, metabolic parameters, and thyroid hormone levels. A total of 1718 FEDN MDD patients were enrolled. The Hamilton Depression Scale (HAMD), Hamilton Anxiety Scale (HAMA), and Positive and Negative Syndrome Scale (PANSS) were used to assess the clinical symptoms of patients. Fasting blood glucose, metabolic parameters, and thyroid hormone levels were measured. After controlling for HAMA and HAMD scores, the suicide attempt rate was 1.88 times higher in MDD patients with glucose disturbances than in MDD patients without glucose disturbances. Compared to non-suicide attempters, suicide attempters among the MDD patients with glucose disturbances had higher scores on HAMD and HAMA, PANSS positive symptoms, as well as higher levels of systolic and diastolic blood pressure, TC, LDL-C, thyroid stimulating hormone (TSH), TgAb, and thyroid peroxidases antibody (TPOAb). The combination of positive symptom score, HDL-C, systolic blood pressure, and marital status distinguished suicide attempters from non-suicide attempters. In addition, HAMA score, HAMD score, and TPOAb were associated with the number of suicide attempts in MDD patients with comorbid glucose disturbances. Our results suggest a high incidence of suicide attempts in MDD patients with comorbid glucose disturbances. Several clinically relevant factors, metabolic parameters, and thyroid hormone function have an impact on suicide attempts in MDD patients with comorbid glucose disturbances.

7.
J Thromb Haemost ; 2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36128771

RESUMO

BACKGROUND AND OBJECTIVES: Platelets are affected by many factors, such as infectious or aseptic inflammation, and different inflammatory states may induce either thrombocytopenia or thrombocytosis. Tumor necrosis factor α (TNFα) is an important inflammatory cytokine that has been shown to affect the activity of hematopoietic stem cells. However, its role in megakaryocyte (MK) development and platelet production remains largely unknown. This study aimed to investigate the effects of TNFα on MK and platelet generation. METHODS AND RESULTS: The ex vivo study with human CD34+ cells demonstrated that TNFα differentially modulated commitment toward the MK lineage. Specifically, a low concentration of 0.5 ng/mL TNFα promoted MK maturation, proplatelet formation, and platelet production, whereas a high concentration of 10 ng/mL or more TNFα exhibited a substantial inhibitory effect on MK and platelet production. The distinct effect of TNFα on MKs was mainly dependent on TNFα receptor 1. TNFα differentially regulated the MAPK-ERK1/2 signaling pathway and the cytoskeletal proteins cofilin and MLC2. The in vivo study with Balb/c mice indicated that low-dose or high-dose TNFα administration differentially affected short-term platelet recovery after bone marrow transplantation. CONCLUSIONS: Our study revealed distinct roles for TNFα in megakaryopoiesis and thrombopoiesis and may provide new insights regarding the treatment for platelet disorders.

8.
Artigo em Inglês | MEDLINE | ID: mdl-36094649

RESUMO

Transarterial embolization (TAE) constitutes the gold standard for the treatment of hepatocellular carcinoma. The effect of combination of TAE and peglated-H1/HGFK1 nanoparticles was explored on hepatocellular carcinoma. MTT and Annexin V-FITC were used to determine the cell viability and apoptosis of HepG2, ml-1, LO2, and VX2 cells after the treatment of HGFK1. Next, the orthotopic rabbit was selected to establish the in situ models of VX2 hepatocellular carcinoma. Nanoparticles were synthesized with peglated-PH1 and used to deliver HGFK1 overexpressing plasmids. MRI was performed to monitor tumor volume after being treated with TAE. The protein expression levels of CD31, CD90, and Ki67 were determined by immunohistochemistry. H&E and TUNEL staining were used to determine the necrosis and apoptosis in vivo. HGFK1 significantly inhibited the proliferation and increased the apoptosis of HepG2 and ml-1 cells (P < 0.05). MRI on 14 days after modeling suggested that the tumor showed ring enhancement. MRI on 7 days and 14 days after interventional therapy showed that tumor volume was significantly inhibited after the treatment with TAE and HGFK1 (P < 0.05). The immunohistochemical results 7 days after interventional therapy indicated that the expressions of CD31, CD90, and Ki67 were significantly lower after treatment with TAE and HGFK1 (P < 0.05). TAE and HGFK1 all extended the survival period of rabbits (P < 0.05). PH1/HGFK1 nanoparticle is an innovative and effective embolic agent, which could limit angiogenesis post-TAE treatment. The combination of TAE with PH1/HGFK1 is a promising strategy and might alter the way that surgeons manage hepatocellular carcinoma (HCC).

9.
Plant Physiol ; 2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36130298

RESUMO

Softening is a key step during fruit ripening that is modulated by the interplay between multiple phytohormones. The antagonistic action of abscisic acid (ABA) and auxin determines the rate of fruit ripening and softening. However, the transcription factors that integrate ABA and auxin signals to regulate fruit softening remain to be determined. In this study, we identified several DNA-binding with One Finger (Dof) transcription factors essential for ABA-promoted fruit softening, based on transcriptome analysis of two sweet cherry (Prunus avium L.) varieties with different fruit firmness. We show that PavDof6 directly binds to the promoters of genes encoding cell wall-modifying enzymes to activate their transcription, while PavDof2/15 directly repress their transcription. Transient overexpression of PavDof6 and PavDof2/15 in sweet cherry fruits resulted in precocious and delayed softening, respectively. In addition, we show that the auxin response factor PavARF8, the expression of whose encoding gene is repressed by ABA, activates PavDof2/15 transcription. Furthermore, PavDof2/6/15 and PavARF8 directly bind to the 9-cis-epoxycarotenoid dioxygenase 1 (PavNCED1) promoter and regulate its expression, forming a feedback mechanism for ABA-mediated fruit softening. These findings unveil the physiological framework of fruit softening and establish a direct functional link between the ABA-PavARF8-PavDofs module and cell wall-modifying genes in mediating fruit softening.

10.
Medicine (Baltimore) ; 101(37): e30337, 2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36123904

RESUMO

BACKGROUND: Left ventricular non-compaction (LVNC) is a rare disease with a poor prognosis. Efforts to improve prognosis are limited by the quality and scope of the available evidence on prognostic factors. METHODS: Pubmed, Embase, China National Knowledge Infrastructure, Cochrane Library, Wanfang, and Baidu Scholar were searched and all relevant studies that examined factors related to LVNC prognosis, published before January 2021, were retrieved. Study quality evaluation and data extraction were independently completed by two authors. Statistical analyses were performed using STATA 15.0 software. RESULTS: A total of 20 cohort studies were included in this study, with a total of 1910 patients. The results of the meta-analysis are as follows: New York Heart Function Association (NYHA) class III/IV (hazard ratio [HR] = 3.93, 95% confidence interval [CI]: 1.66-9.29), (NT-proBNP) increased (HR = 1.98, 95% CI: 1.10-3.58), left ventricular ejection fraction (LVEF) decreased (HR = 1.04, 95% CI: 1.03-1.06), left ventricular end-diastolic diameter (LVEDD) increased (HR = 1.03, 95% CI: 1.01-1.06) was an independent poor prognostic factor, and body mass index (HR = 0.80, 95% CI: 0.64-0.98) was an independent protective factor. Creatinine (CR) level (HR = 1.09, 95% CI: 0.95-1.25) and late gadolinium-enhanced (LGE) imaging (HR = 3.1, 95% CI: 0.85-11.31) has no statistical significance in the prognosis of LVNC. CONCLUSION: In LVNC patients, NYHA class III/IV, elevated N-terminal pro-brain natriuretic peptide (NT-proBNP) levels, decreased LVEF, and increased LVEDD may lead to poor prognosis, and increased body mass index may improve the prognosis of LVNC. Further clinical research with large sample sizes and long-term follow-ups should be conducted. PROSPERO REGISTRATION NUMBER: 42020152706.


Assuntos
Gadolínio , Função Ventricular Esquerda , Creatinina , Humanos , Prognóstico , Volume Sistólico
11.
Curr Psychol ; : 1-9, 2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-36068881

RESUMO

The present study was designed to investigate the association and the underlying mechanism between parental conflict and adolescent depression during the COVID-19 pandemic. In a longitudinal study, a total of 655 Chinese adolescents ranging from 13 to 16 years old completed a three-wave survey (W1, W2, W3) via a survey website. The data was collected three times: March 15-20, 2020 (W1, the outbreak period of the COVID-19 pandemic in Mainland China), June 20-25, 2020 (W2, the trough stage), and December 15-20, 2020 (W3, six months after the trough stage). The SPSS 16.0 software was used to investigate the relationships among study variables. The findings showed that a double-hump effect was found for depression detection among adolescents during the pandemic, with depression rates in W1 (26.9%) and W3 (29%) were higher than that in W2 (21.9%). The parental conflict subscales of content and resolution had a greater impact on adolescent adjustment than other subscales. The parental conflict had direct and indirect impacts (through reducing family support and increasing burdensomeness) on adolescent depression symptoms in W3. It was concluded that when the COVID-19 pandemic was in a trough curve for more than six months, adolescent adjustment was significantly impacted by the pandemic, and parental conflict was an important risk factor in predicting individual adjustment. Therefore, family intervention is recommended when improving adolescent adjustment during the COVID-19 pandemic.

12.
J Oncol ; 2022: 2813938, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36081671

RESUMO

Homoharringtonine- (HHT-) based HHT, aclarubicin, and cytarabine (HAA) induction regimen is the first-line therapy for nonelder acute myeloid leukemia (AML) patients in China. However, drug resistance is a new challenge, and little attention has been devoted to excavating resistant mechanisms. This study used the classic method to construct six HHT-resistant cell lines with a gradually increasing resistance index (RI) to discover HHT drug resistance mechanisms dynamically. After HHT resistance, the cell growth rate decreased, cell cycle delayed, and P-glycoprotein (p-gp, CD243) expression levels increased. Furthermore, we explored the changes in transcriptomics between HHT-sensitive and HHT-resistant cells using RNA-sequence. Through Kyoto Encyclopedia of Genes and Genomes (KEGG), Gene Ontology (GO), and hub gene analyses, we found that immune activity, especially G-protein coupled receptor (GPR) and related molecules, may mediate HHT resistance. Moreover, Calcitonin Receptor-Like (CALCRL) and G Protein Subunit Alpha I1 (GNAI1), which belong to GPRs, were stimulated in HHT-resistant cell strains in vitro and vivo, indicating that they may play a critical role in HHT resistance. In addition, these two genes have prognostic significance for AML patients. Taken together, we successfully constructed HHT-resistant cell lines with dynamic RIs and explored the resistance mechanisms, which will help identify new drugs for HHT-resistant AML patients.

13.
Parkinsonism Relat Disord ; 103: 122-128, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36108429

RESUMO

OBJECTIVE: Depression and cognitive impairment are both common non-motor symptoms of Parkinson's disease (PD). Brain-derived neurotrophic factor (BDNF) may play an important role in both cognitive function and depression. In this study, we examined BDNF levels, cognitive function, and the relationship between BDNF and cognitive function in PD patients with and without depressive symptoms, which has not been reported yet. METHODS: We recruited 96 PD patients with (n = 46) and without depression (n = 50) and 102 controls and examined the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and BDNF levels in all groups. The Zung Self-Rating Depression Scale (SDS) was used to assess the severity of depression and the Hoehn-Yahr staging test was used to assess motor abilities in PD patients. RESULTS: BDNF levels were lower in patients with depressive symptoms than in patients without depressive symptoms (p<0.01). The RBANS total score and the immediate memory, language and attention scores were lower in patients with depressive than in patients without depressive (all p < 0.05). Multiple regression analysis showed that BDNF was independent contributor to immediate memory, language and RBANS total score in the patients with depressive symptoms. BDNF and SDS were independent contributors to attention, and SDS was an independent contributor to delay memory (all p < 0.001). CONCLUSIONS: BDNF may be involved in the pathophysiology of PD patients with depressive symptoms. Moreover, the association between BDNF and cognitive performance only in patients with depressive symptoms suggest a close relationship in BDNF, cognition and depressive symptoms in PD patients.

14.
Materials (Basel) ; 15(18)2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36143743

RESUMO

In recent years, conductive polymer composites have been widely studied for their electrical conductivity and electromagnetic shielding effects due to their advantages of light weight, simple preparation methods, and structural design versatility. In this study, oxidized multi-walled carbon nanotubes/waterborne polyurethane composites (OCNT/WPU) were prepared by grafting oxidized carbon nanotubes onto polyurethane molecular chains through in situ polymerization, using environmentally friendly waterborne polyurethane as the polymer matrix. Then, the OCNT/WPU structure was broken by high shear force, and the loading of CNTs was increased by adsorption, and a new composite structure was designed (denoted by OCWPU). The structure and morphology of OCNT/WPU and OCWPU were characterized by FT-IR and SEM. The structure and morphology of OCWPU with different multi-walled carbon nanotube loadings (CNTs/OCWPU) were characterized by SEM, Raman. Finally, the electrical conductivity and the electromagnetic shielding properties of the composites were investigated. It was found that after application of high shear force, the structure of OCWPU was disrupted and the surface activity of the material increased. With the increase in CNTs content, CNTs formed a rosette structure in the polyurethane matrix and covered the surface, and its electromagnetic shielding effect in X-bond (8.2-12.4 Ghz) would be able to reach 23 dB at 5% CNTs/OCWPU and 66.5 dB at 50% CNTs/OCWPU to meet the commercial needs. With 50% CNTs/OCWPU, an electrical conductivity of 5.1 S/cm could be achieved. This work provides a novel idea for the structural design of conductive polymer composites, which can achieve greater performance with the same carbon nanotube content.

15.
Ying Yong Sheng Tai Xue Bao ; 33(9): 2413-2421, 2022 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-36131657

RESUMO

The situations are complex and variant in the three stages of "carbon emission peak", "rapid reduction of carbon emission" and "deep decarbonization for carbon neutrality" in China's carbon neutralization roadmap. Forest carbon sequestration is an important means to achieve the goal of carbon neutralization in China. Its intertemporal allocation is a vital way to balance industrial emission reduction and forest carbon sequestration, reduce the cost of carbon neutrality, and gradually achieve the goal of carbon neutrality based on optimal cost. Based on the cost optimization allocation theory, we simulated the cost change process of three stages of carbon neutralization in China by quoting the theory of marginal carbon sequestration cost and combining with the existing domestic marginal abatement cost theory. The results showed that annual forest carbon sequestrations with the optimal cost in China was 20 million t, 775 million t and 1.982 billion t respectively in the three stages of "carbon emission peak", "rapid reduction of carbon emission" and "deep decarbonization for carbon neutrality", accounting for 1.8%, 17.5%, and 37.6% of the total emission reduction in each period. Compared with the way relying only on industrial emission reduction, forest carbon sequestration under the optimal cost design reduced the total cost by 48, 79136, and 909253 million US$ in the three stages of carbon neutralization, respectively. Due to the limited cost advantage of forest carbon sequestration, industrial emission reduction should be emphasized in the "carbon emission peak" stage. In the "rapid reduction of carbon emissions" stage, the cost advantage of forest carbon sequestration will be increasingly prominent. In the stage of "deep decarbonization for carbon neutrality", it is necessary to fully exploit the cost advantage of forest carbon sequestration to achieve the goal of "zero carbon" to avoid the risk of high costs, especially for industries with high decarbonization cost or that will never be completely decarbonized. The optimal cost design for forest carbon sequestration can save 988.437 billion US $ in carbon-neutral costs.


Assuntos
Sequestro de Carbono , Gases de Efeito Estufa , Carbono/análise , Dióxido de Carbono/análise , China , Florestas
16.
Comput Biol Med ; 150: 106076, 2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36137320

RESUMO

Segmentation of the liver and tumours from computed tomography (CT) scans is an important task in hepatic surgical planning. Manual segmentation of the liver and tumours is a time-consuming and labour-intensive task; therefore, a fully automated method for performing this segmentation is particularly desired. An automatic two-step liver and tumour segmentation method is presented in this paper. A cascade framework is used during the segmentation process, and a fully connected conditional random field (CRF) method is used to refine the tumour segmentation result. First, the proposed fractal residual U-Net (FRA-UNet) is used to locate and initially segment the liver. Then, FRA-UNet is further used to predict liver tumours from the liver region of interest (ROI). Finally, a three-dimensional (3D) CRF is used to refine the tumour segmentation results. The improved fractal residual (FR) structure effectively retains more effective features for improving the segmentation performance of deeper networks, the improved deep residual block can utilise the feature information more effectively, and the 3D CRF method smooths the contours and avoids the tumour oversegmentation problem. FRA-UNet is tested on the Liver Tumour Segmentation challenge dataset (LiTS) and the 3D Image Reconstruction for Comparison of Algorithm Database dataset (3DIRCADb), achieving 97.13% and 97.18% Dice similarity coefficients (DSCs) for liver segmentation and 71.78% and 68.97% DSCs for tumour segmentation, respectively, outperforming most state-of-the-art networks.

17.
Org Lett ; 24(37): 6851-6856, 2022 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-36103354

RESUMO

Triacylamines with Cs symmetry have been explored in asymmetric organocatalysis, leading to the development of a novel catalytic enantioselective desymmetrization of prochiral triacylamines by methanolysis under the catalysis of chiral pseudopeptidic guanidine-guanidinium salt having a weakly coordinating anion. This organocatalytic methodology provides an effective approach to the synthetically useful chiral imide-esters with a 1,5-dicarbonyl moiety, and its synthetic potential has been manifested in the asymmetric synthesis of two GABA analogue drugs, (R)-Baclofen·HCl and (S)-Pregabalin.

18.
Emerg Med Int ; 2022: 7806659, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36059558

RESUMO

Objective: To determine the role of Jinhuang Powder to prevent adverse effects of subcutaneous injection of enoxaparin sodium. Methods: The clinical data of 97 patients with cervical cancer who were treated with subcutaneous injection of enoxaparin through the lower margin of the deltoid muscle of the upper arm in Zhejiang Tumor Hospital from August 2020 to August 2021 were retrospectively analyzed. All patients were divided into the control group (n = 39) and the research group (n = 58) according to the different use time periods of Jinhuang Powder. The research group was treated with Jinhuang Powder and enoxaparin sodium at the same time. The control group started to use Jinhuang Powder after the adverse reactions occurred. The induration, subcutaneous bleeding events, and pain were statistically analyzed. Results: The incidence of induration (3.4% vs 15.4%, P=0.036) and subcutaneous hemorrhage (37.9% vs 76.9%, P=0.003) in the research group was significantly lower than that in the control group. The pain in the research group was lighter than that in the control group (grade 0-4 pain: 70% vs 28.2%, 19% vs 30.8%, 8.6% vs 23.1%, 1.7% vs 12.8%, 1.7% vs 5.1%, P=0.001). Conclusion: Preventive use of Jinhuang Powder can significantly reduce the incidence of subcutaneous induration and subcutaneous bleeding and can effectively alleviate the local pain of injection. It is worthy of further study to clarify its role and mechanism.

19.
Artigo em Inglês | MEDLINE | ID: mdl-36082970

RESUMO

Oxidative N-heterocyclic carbene (NHC) organocatalysis, typically leading to the formation of acyl azolium reactive intermediates, constitutes one of the most important activation strategies for the NHC-catalyzed chemical transformations. Here, we report an unprecedented oxidative radical NHC catalysis by using peroxyester as the external single-electron oxidant to realize divergent difunctionalization of olefins. The key to success of this chemistry is the catalytic generation of oxygen radicals that could trigger an intermolecular hydrogen atom transfer to activate the inert C-H bonds, thereby enabling the productive radical relay process. With this protocol, commonly used general chemicals could serve as radical precursors to allow efficient synthesis of value-added products in a straightforward and cost-effective manner. Preliminary mechanistic investigations, including control experiments and DFT calculations, shed light on the NHC organocatalytic radical reaction mechanism.

20.
Artigo em Inglês | MEDLINE | ID: mdl-36078660

RESUMO

The prevalent air pollution along the Yangtze River Economic Belt (YREB) possesses a significant threat to the natural environment, which further affects nearby tourism destination development. The paper seeks to assess the impact of air pollution on tourism in this region through a 2002-2012 panel data of 31 prefecture-level cities, along with geographic information system (GIS) and cluster analyses. The results reveal that air pollution is negatively associated with the number of inbound tourists along the YREB. In general, when air pollution intensifies by 1%, the number of inbound tourists decreases by 1.171%. This impact is more evident when air pollution is more severe, in the long term, and in areas that are larger, more central, and with more tourism resources. The paper contributes to the literature by addressing common limitations in previous studies and providing a more comprehensive evaluation of air pollution's impact on inbound tourism in the YREB. Practical implications regarding public policies and development directions based on air pollution periods, regions, and tourism resource allocations are provided.


Assuntos
Poluição do Ar , Rios , Poluição do Ar/análise , China , Cidades , Desenvolvimento Econômico , Turismo
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