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1.
Water Environ Res ; 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33565667

RESUMO

Researchers are trying to tackle water scarcity in numerous ways. One of those ways is the use of nanotechnology in water processing and purification. The current work involves the fabrication and optimization of activated carbon and graphene-based hybrid water purification system. Five different concentrations of methylene blue and deionized water (DI) water dye solutions were used, and they were filtered in three different cycles. For the potential usage on the consumer side, a small-scale, low-cost water filter is developed using activated carbon, commercial filter paper, and graphene nanoplatelets. The filter paper is used to hold mixtures of the activated carbon and graphene nanoplatelets within the water filter. The conductivity, TDS, and pH are measured for the feed water and the processed water using an Oakton EcoTestr and Apera Instruments PH60 Premium Pocket pH meter respectively. A UV-Vis spectrometer is used to measure the absorption of solutions. The distribution and adsorption of the dye particles were observed by scanning electron microscopy.

2.
Sci Total Environ ; 774: 145198, 2021 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-33611007

RESUMO

Biodiversity-biomass relationships have been debated for decades and remain subject to controversy. Understanding the relationship between biodiversity and biomass will be crucial for soil and water conservation of the whole basin of the Yellow River. The positive effects of biodiversity on aboveground biomass are altered via two fundamental mechanisms-niche complementarity and selection effects-and are modulated by environmental context and community structure in natural communities. Most studies of biodiversity-biomass relationships have focused on grasslands and forests, rather than on shrublands. We combine multiple biotic variables (biodiversity, functional identity and community structural attributes) and environmental context with aboveground biomass across shrubland habitat types (temperate hilly, temperate montane and subtropical montane) at neighbourhood and community spatial scales, to evaluate the effects of these factors on shrubland aboveground biomass, in the Yellow River basin. We found aboveground biomass was influenced primarily by the community-weighted mean plant maximum height, followed by species richness and community-weighted mean specific leaf area. Furthermore, individual plant size inequality, mean annual precipitation and water availability either directly or indirectly influenced aboveground biomass. The biodiversity-aboveground biomass relationship was stronger at the broader spatial scale. Thus, our findings indicate that both niche complementarity and selection effects shape the effects of biodiversity on shrubland aboveground biomass, although selection effects are more important. Moreover, they indicate that water is the most important environmental factor for determining aboveground biomass, and suggest that community structure and spatial scale could influence shrubland aboveground biomass and its response to biodiversity.

3.
Chem Commun (Camb) ; 57(12): 1474-1477, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33443248

RESUMO

For prevention of the coronavirus disease 2019 caused by the novel coronavirus SARS-CoV-2, an effective vaccine is critical. Herein, several potential peptide epitopes from the spike protein of SARS-CoV-2 have been synthesized and covalently linked with the cross-reactive material (CRM197). Immunization of mice with the resulting conjugates induced high titers of IgG antibodies against the spike protein. Importantly, the post-immune sera effectively neutralized SARS-CoV-2 pseudovirus, suggesting the epitopes identified are protective, and these conjugates are promising leads for anti-SARS-CoV-2 vaccine development.

4.
Atherosclerosis ; 317: 10-15, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33333343

RESUMO

BACKGROUND AND AIMS: The impact of residual cholesterol risk (RCR) on plaque characteristics is not fully understood. The study aims to explore the relationship between RCR and plaque features in patients presenting with acute coronary syndrome (ACS). METHODS: All ACS patients undergoing pre-intervention optical coherence tomography (OCT) with high-sensitivity C-reactive protein (hs-CRP) <2 mg/L on admission were retrospectively enrolled from January to December 2017, at Beijing Anzhen Hospital, Capital Medical University. RCR was defined as low density lipoprotein cholesterol (LDL-C) ≥1.8 mmol/L. Patients were divided into the RCR and non-RCR groups according to baseline LDL-C. RESULTS: A total of 90 patients (94 vessels) were included, with 50 in the RCR group and 40 in the non-RCR group, respectively. Compared with the non-RCR group, patients in the RCR group were younger (54.0 ± 11.04 vs. 58.4 ± 9.59, p = 0.049) and had a higher incidence of multivessel disease (6.0% vs. 2.5%, p = 0.028). With regard to plaque characteristics, fibrous plaque (0.0% vs 12.5%, p = 0.003) was less and fibroatheroma (79.6% vs. 50.0%, p = 0.028) was more frequently seen in the RCR group. Patients in the RCR group were more prone to present with plaque rupture (24.1% vs 5.0%, p = 0.008). Cholesterol crystal (22.2% vs 12.5%, p = 0.226) and thin-cap fibroatheroma (25.9% vs. 12.5%, p = 0.109) were more common in the RCR group, though without statistical difference. Multivariate logistic regression showed that RCR (odds ratio [OR]: 7.95, p = 0.011) and smoking (OR: 4.08, p = 0.026) were independent risk factors of plaque rupture in our patients. CONCLUSIONS: ACS patients with RCR are more likely to have atherosclerotic plaque and plaque rupture, indicating a more vulnerable plaque phenotype.

5.
J Colloid Interface Sci ; 582(Pt A): 112-123, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32814219

RESUMO

Multifunctional cotton fabrics have attracted significant attention as next-generation wearable materials. Herein, we report a facile method for the fabrication of flexible and wearable cotton fabrics with ultra-high electromagnetic interference (EMI) shielding, antibacterial, and superhydrophobic properties. Cotton fabrics were first coated chemically with silver nanoparticles using polydopamine as adhesive and then with hydrophobic polydimethylsiloxane or polyimide. The introduction of polydopamine significantly increased the bond between silver nanoparticles and cotton fibers, thereby preventing silver nanoparticles from falling off the surface. The composite fabrics exhibited a high conductivity of ~1000 S/cm, and their EMI shielding effectiveness increased up to ~110 dB. The composite fabrics exhibited excellent self-cleaning performance and acid-alkali corrosion resistance because of their superhydrophobicity. Notably, the fabric composites showed a significant antibacterial action against Staphylococcus aureus and Escherichia coli.

6.
Front Cardiovasc Med ; 7: 590975, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33304932

RESUMO

Background: The efficacy and safety of transcatheter aortic-valve replacement (TAVR) vs. surgical aortic valve replacement (SAVR) for low- to intermediate-surgical risk patients remains uninvestigated. Objectives: We aimed to investigate the efficacy and safety of transcatheter aortic-valve replacement (TAVR) vs. surgical aortic valve replacement (SAVR) for low-intermediate surgical risk patients. Methods: PubMed, Cochrane Library, and Embase databases were searched to identify potential references. Only randomized controlled trials (RCTs) or observational studies using propensity score matching were eligible for screening. The primary endpoint was all-cause death. The secondary outcomes were bleeding, stroke, myocardial infarction (MI), and other complications of aortic-valve replacement. In addition, we performed subgroup analysis based on surgical risk and study type. Results: Eight RCTs and 13 observational studies covering 12,467 patients were included in the current meta-analysis. For patients with low-surgical risk, compared with SAVR, TAVR was found to be associated with a lower mortality at a follow-up period of 1 year (odds ratio, OR: 0.66, 95% CI: [0.46, 0.96], P = 0.03). This benefit disappeared when the follow-up was extended to 2 years (OR: 0.89, 95% CI: [0.61, 1.30], P = 0.56). For patients with intermediate-surgical risk, TAVR showed to have similar mortality with SAVR regardless of follow-up period (30-day, 1-year, or 2-year). TAVR could reduce the incidence of bleeding, AF, and AKI. For complications, such as MI and stroke, TAVR exhibited to have similar safety with SAVR. However, TAVR was found to be associated with a higher incidence of reintervention, major vascular complication, paravalvular leak, and PPI. Conclusion: For patients with a low-to-intermediate surgical risk, TAVR has at least an equivalent clinical effect to SAVR for 2 years after the procedure.

7.
J Glob Health ; 10(2): 021103, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33312513

RESUMO

Background: To prevent the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), strict control of person-to-person transmission is essential. Family transmission is the most common route of transmission; however, family transmission patterns and outcomes are not well understood. Methods: We enrolled confirmed cases discharged from Wuhan Zhuankou Fangcang Shelter Hospital from February 17, 2020 to March 8, 2020 along with the family members they had contact with, to evaluate baseline characteristics, family transmission patterns and outcomes. The follow-up period lasted until May 8, 2020. Results: This study evaluated 369 participants, which included 100 patients admitted to the shelter hospital and the family members they had contact with. Family transmission occurred in 62% of household, with 190 cases confirmed to have SARS-CoV-2 infection. There were eight patterns of family transmission, and spousal transmission (44/83, 53.0%) was the most common pattern, especially in the middle-age generation group (35/83, 42.2%). The homes of the families in which all members were infected had a smaller per capita area than those of other families (29.1 ± 11.89 cm2 vs 41.0 ± 19.70 cm2, respectively, P = 0.037), and the per capita area was negatively associated with the number of infected family members (R = -0.097, P = 0.048). Of the 190 confirmed cases, the 113 mild or moderate cases were monitored in fangcang (including Wuhan Zhuankou Fangcang and other fangcang), and the 59 severe cases were treated at designated hospitals. By the end of follow-up, 185 patients recovered and returned home after completing at least 14 days of isolation at the community quarantine center, four died in hospitals, and one died at home before hospitalization. Interestingly, four patients had positive nucleic acid test results after previous negative results, though none of these patients were re-hospitalized, and none of their close contacts reported an infection. Conclusions: Our data found eight family transmission patterns, of which spousal transmission was the most common. Some patients were also found to have positive test results during follow-up.


Assuntos
/epidemiologia , Família , Adolescente , Adulto , Idoso , Criança , China/epidemiologia , Comorbidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Unidades Móveis de Saúde , Pandemias , Índice de Gravidade de Doença , Adulto Jovem
8.
Biol Trace Elem Res ; 2020 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-33184740

RESUMO

The objective of this study was to assess the contamination levels of arsenic (As), lead (Pb), chromium (Cr), and cadmium (Cd) in raw milk and the subsequent potential health risk to local consumers close to leather-processing plants in China. The As and Pb concentrations in milk from contaminated areas were 0.43 ± 0.21 and 2.86 ± 0.96 µg/L, respectively, which were significantly higher than in milk from unpolluted farm, with values of 0.20 ± 0.05 and 2.32 ± 0.78 µg/L, respectively. The Cr and Cd levels in milk from contaminated areas were 1.21 ± 1.57 and 0.15 ± 0.04 µg/L, respectively, which were slightly higher than in milk from unpolluted farm, with values of 0.87 ± 0.61 and 0.13 ± 0.04 µg/L, respectively, (P > 0.05). Target hazard quotient (THQ) and hazard index (HI) values for As, Pb, Cr, and Cd from milk consumption were calculated for individuals aged 3 to 69. The THQ followed a descending order of As > Pb > Cr > Cd, with values of 0.0066-0.0441, 0.0033-0.0220, 0.0019-0.0124, and 0.0007-0.0046, respectively. The HI values (0.0124-0.0832) were far below the threshold of 1.

9.
Cancer Lett ; 2020 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-33160002

RESUMO

Localized cranial radiotherapy is a dominant treatment for brain cancers. After being subjected to radiation, the central nervous system (CNS) exhibits targeted effects as well as non-targeted radiation bystander effects (RIBE) and abscopal effects (RIAE). Radiation-induced targeted effects in the CNS include autophagy and various changes in tumor cells due to radiation sensitivity, which can be regulated by microRNAs. Non-targeted radiation effects are mainly induced by gap junctional communication between cells, exosomes containing microRNAs can be transduced by intracellular endocytosis to regulate RIBE and RIAE. In this review, we discuss the involvement of microRNAs in radiation-induced targeted effects, as well as exosomes and/or exosomal microRNAs in non-targeted radiation effects in the CNS. As a target pathway, we also discuss the Akt pathway which is regulated by microRNAs, exosomes, and/or exosomal microRNAs in radiation-induced targeted effects and RIBE in CNS tumor cells. As the CNS-derived exosomes can cross the blood-brain-barrier (BBB) into the bloodstream and be isolated from peripheral blood, exosomes and exosomal microRNAs can emerge as promising minimally invasive biomarkers and therapeutic targets for radiation-induced targeted and non-targeted effects in the CNS.

10.
Artigo em Inglês | MEDLINE | ID: mdl-33085904

RESUMO

Infants born under 1500 grams have an increased incidence of necrotizing enterocolitis in the ileum and the colon which is a life-threatening intestinal necrosis. This is in part due to excessive inflammation in the immature intestine to colonizing bacteria because of an immature innate immune response. Breastmilk complex carbohydrates create metabolites of colonizing bacteria in the form of short-chain fatty acids (SCFAs). We studied the effect of breastmilk metabolites, SCFAs, on immature intestine with regard to anti-inflammatory effects. This showed that acetate, propionate and butyrate were all anti-inflammatory to an IL-1ß inflammatory stimulus. In this study, to further define the mechanism of anti-inflammation, we created transcription profiles of RNA from immature human enterocytes after exposure to butyrate with and without an IL-1ß inflammatory stimulus. We demonstrated that butyrate stimulates an increase in tight-junction and mucus genes and if we inhibit these genes the anti-inflammatory effect is partially lost. SCFAs, products of microbial metabolism of complex carbohydrates of breastmilk oligosaccharides, have been found with this study to induce an anti-IL-1ß response that is associated with an upregulation of tight junctions and mucus genes in epithelial cells (H4 cells). These studies suggest that breastmilk in conjunction with probiotics can reduce excessive inflammation with metabolites that are anti-inflammatory and stimulate an increase in the mucosal barrier.

11.
Toxins (Basel) ; 12(10)2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-32998222

RESUMO

Mycotoxins are fungal metabolites that occur in human foods and animal feeds, potentially threatening human and animal health. The intestine is considered as the first barrier against these external contaminants, and it consists of interconnected physical, chemical, immunological, and microbial barriers. In this context, based on in vitro, ex vivo, and in vivo models, we summarize the literature for compromised intestinal barrier issues caused by various mycotoxins, and we reviewed events related to disrupted intestinal integrity (physical barrier), thinned mucus layer (chemical barrier), imbalanced inflammatory factors (immunological barrier), and dysfunctional bacterial homeostasis (microbial barrier). We also provide important information on deoxynivalenol, a leading mycotoxin implicated in intestinal dysfunction, and other adverse intestinal effects induced by other mycotoxins, including aflatoxins and ochratoxin A. In addition, intestinal perturbations caused by mycotoxins may also contribute to the development of mycotoxicosis, including human chronic intestinal inflammatory diseases. Therefore, we provide a clear understanding of compromised intestinal barrier induced by mycotoxins, with a view to potentially develop innovative strategies to prevent and treat mycotoxicosis. In addition, because of increased combinatorial interactions between mycotoxins, we explore the interactive effects of multiple mycotoxins in this review.

12.
Ther Adv Chronic Dis ; 11: 2040622320961599, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33062238

RESUMO

Background: Patients with type 2 diabetes mellitus (T2DM) have an increased risk of fracture compared with those without T2DM. Some oral glucose-lowering agents may increase the incidence of fracture. Whether sodium-glucose co-transporter 2 inhibitors (SGLT2is) are associated with increased risk of fracture remains unclear. Methods: We retrieved articles from PubMed, Embase, Cochrane Library database, and other sources up to 24 October 2019. We included randomized controlled trials (RCTs) that reported fractures and analyzed the fracture incidence of SGLT2i, canagliflozin, dapagliflozin, and empagliflozin. Subgroup analysis was also performed based on baseline characteristics. Results: A total of 78 RCTs with 85,122 patients were included in our analysis. The overall SGLT2i fracture incidence was 2.56% versus 2.77% in the control group [odds ratio (OR), 1.03; 95% confidence interval (CI) (0.95, 1.12); p = 0.49]. Compared with the control treatment, treatment with canagliflozin led to a higher rate of fractures [OR, 1.17; 95% CI (1.00, 1.37); p = 0.05], but no significant difference was observed when compared with dapagliflozin [OR, 1.02; 95% CI (0.90, 1.15); p = 0.79] or empagliflozin [OR, 0.89; 95% CI (0.73, 1.10); p = 0.30]. Subgroup analysis showed that, in a follow-up of less than 52 weeks, SGLT2i decreased the incidence of fracture by 29% [OR, 0.71; 95% CI (0.55, 0.93); p = 0.01], but this benefit was lost when the follow-up extended to more than 52 weeks [OR, 1.08; 95% CI (0.98, 1.18); p = 0.12]. Conclusion: Canagliflozin seems to increase the risk of fracture, while other SGLT2is do not result in a higher incidence of fracture.

13.
Artigo em Inglês | MEDLINE | ID: mdl-32920996

RESUMO

AIMS: To analyze the factors affecting the prognosis of hepatoblastoma (HB) with lung metastasis in children. METHODS: The HB patients with lung metastases admitted to Beijing Tongren Hospital, Capital Medical University were collected. The clinical data, overall results, and prognostic factors were analyzed. Multivariate analysis was done by the Cox proportional hazards model for patients' prognosis. RESULTS: Finally, 98 HB patients (64 boys and 34 girls) with lung metastasis met the inclusion criteria, in which 64 patients had lung metastases at diagnosis (median age, 22.3 months) and 34 patients developed lung metastases while on treatment (median time, 6.5 months). The survival time and 5-year survival rate of patients with standard treatment were significantly longer than that of without standard treatment (P < .001). The survival time and 3-year survival rate had no difference between patients underwent lung metastasectomy and without lung metastasectomy (P = .099), between different diagnosis time of lung metastasis in HB patients (P = .37), between each histology type (P = .313), and different PRETEXT stage (P = .353). While the survival time and 3-year survival rate of patients with lung metastasis alone were significantly longer than that of patients with extrapulmonary involvement (P = .007). Multivariate Cox proportional hazards model revealed that the lung metastasis accompanied with extrapulmonary involvement was a risk factor affecting prognosis (HR = 0.460, 95% CI 0.239-0.888). CONCLUSIONS: For HB children with lung metastatic, extrapulmonary involvement might be a high-risk factor of prognosis and standardized treatment with lung metastasectomy might prolong the survival time of them.

14.
J Thorac Dis ; 12(8): 4531-4535, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32944369
15.
J Int Med Res ; 48(8): 300060520942619, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32812463

RESUMO

OBJECTIVE: Bupivacaine is an amide local anesthetic with possible side effects that include an irregular heart rate. However, the mechanism of bupivacaine-induced cardiotoxicity has not been fully elucidated, thus we aimed to examine this mechanism. METHODS: We performed electrocardiogram recordings to detect action potential waveforms in Sprague Dawley rats after application of bupivacaine, while calcium (Ca2+) currents in neonatal rat ventricular cells were examined by patch clamp recording. Western blot and quantitative real-time polymerase chain reaction assays were used to detect the expression levels of targets of interest. RESULTS: In the present study, after application of bupivacaine, abnormal action potential waveforms were detected in Sprague Dawley rats by electrocardiogram recordings, while decreased Ca2+ currents were confirmed in neonatal rat ventricular cells by patch clamp recording. These alterations may be attributed to a deficiency of CaV1.3 (L-type) Ca2+ channels, which may be regulated by the multifunctional protein calreticulin. CONCLUSIONS: The present study identifies a possible role of the calreticulin-CaV1.3 axis in bupivacaine-induced abnormal action potentials and Ca2+ currents, which may lead to a better understanding anesthetic drug-induced cardiotoxicity.

16.
Cell Death Dis ; 11(7): 511, 2020 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-32641707

RESUMO

Our previous work demonstrated that Epithelial Splicing Regulatory Protein 1 (ESRP1) could inhibit the progression of lung adenocarcinoma (ADC). When ESRP1 was upregulated, the interferon (IFN) pathway was activated and Interferon-stimulated gene 15 (ISG15) expression increased exponentially in our microarray result. In this study, we aim to explore the function of ISG15 and its interactions with ESRP1 and to provide new insights for ADC treatment. ISG15 expression in lung ADC tissues was determined by immunohistochemistry (IHC) staining. The effect of ISG15 on lung ADC progression was examined by in vitro and in vivo assays. The mechanism of action on ESRP1 regulating ISG15 was investigated using Western blotting, RT-qPCR, immunofluorescence staining, chromatin immunoprecipitation, and a dual luciferase reporter system. The ISGylation between ISG15 and ESRP1 was detected by co-immunoprecipitation. Patients with high ISG15 expression were associated with higher survival rates, especially those with ISG15 expression in the nucleus. In vitro and in vivo experiments showed that upregulation of ISG15 inhibited EMT in lung ADC. ESRP1 upregulated the expression of ISG15 through CREB with enriched ISG15 in the nucleus. Importantly, ISG15 promoted ISGylation of ESRP1 and slowed the degradation of ESRP1, which demonstrated that ESRP1 and ISG15 formed a positive feedback loop and jointly suppressed EMT of lung ADC. In conclusion, ISG15 serves as an independent prognostic marker for long-term survival in lung ADC patients. We have revealed the protective effect of ISG15 against lung ADC progression and the combinatorial benefit of ISG15 and ESRP1 on inhibiting EMT. These findings suggest that reconstituting ISG15 and ESRP1 may have the potential for treating lung ADC.

17.
J Agric Food Chem ; 68(32): 8580-8588, 2020 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-32689796

RESUMO

Glycyrrhetinic acid (GA), a pentacyclic triterpenoid aglycone, is the major functional component in licorice which mainly exists in the form of functional glycosides in licorice. The introduction of a sugar moiety to the C-3 OH of GA to yield glycosylated derivatives has been reported, but the late-stage glycosylation of GA-3-O-sugar to form rare GA glycosides with more complexed glycosyl decoration has been rarely reported. In this study, a unique UDP-galactosyltransferase GmSGT2 from Glycine max was found to transfer a galactose to the C2 position of the sugar moiety of GA-3-O-monoglucuronide (GAMG) and GA-3-O-monoglucose. In addition to UDP-galactose, GmSGT2 also recognizes UDP-glucose, UDP-xylose, and UDP-arabinose with relative activities of 32.1-89.2%. Based on a test of 12 typical natural products, GmSGT2 showed high specificity toward the pentacyclic triterpenoid skeleton as the sugar acceptor. Molecular docking was performed to elucidate the substrate recognition mechanism of GmSGT2 toward GAMG.

18.
Pharmacol Res ; 159: 104992, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32505833

RESUMO

Chronic infection of Hepatitis B virus (HBV) has long been recognized as a major risk factor in the initiation and development of hepatocellular carcinoma (HCC), contributing to over half the cases of HCC worldwide. Transformation of the liver with HBV infection to HCC mainly results from long-term interaction between HBV and the host hepatocytes via a variety of mechanisms, including HBV DNA integration, prolonged expression of the viral HBx regulatory protein and/or aberrant preS/S envelope proteins, and epigenetic dysregulation of tumor suppressor genes. While there have been several failures in the development of drugs for HCC, the immune-tolerant microenvironment of this malignancy suggests that immunotherapeutic agents could provide benefits for these patients. This is supported by recent data showing that immunotherapy has promising activity in patients with advanced HCC. In this review, we provide an overview of HBV-induced HCC and recent immune based approaches for the treatment of HCC patients.

19.
J Phys Chem A ; 124(27): 5615-5620, 2020 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-32538628

RESUMO

Sulfuryl fluoride (SO2F2) plays an important role in the operation of gas-insulated switchgear (GIS) equipment where it is widely used as the characteristic gas for discharge diagnostics. However, the formation mechanism of SO2F2 is currently unclear, and as a consequence, we have employed a range of ab initio methods to investigate the hydrolysis reaction of SOF4 that is known to afford SO2F2 in the gas phase. These results suggest that two H2O molecules are incorporated into a low energy transition state to afford an H-bond network that facilitates proton transfer during the hydrolysis of SOF4.

20.
Sci Rep ; 10(1): 5826, 2020 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-32242029

RESUMO

Research in recent decades has confirmed that biodiversity influences ecosystem productivity; however, the potential mechanisms regulating this process remain subject to controversy, due to variation across ecosystems. Here, the effects of biodiversity on ecosystem productivity were evaluated using three variables of biodiversity (taxonomic diversity, functional identity, and functional diversity) and surrounding environmental conditions in a coastal saline meadow located on the south coast of Laizhou Bay, China. At this site, the shrub and field layers were primarily dominated by Tamarix chinensis and natural mesic grasses, respectively. Our results showed that functional identity, which is quantified as the community weighted mean of trait values, had greater explanatory ability than taxonomic and functional diversity. Thus, ecosystem productivity was determined disproportionately by the specific traits of dominant species. T. chinensis coverage was a biotic environmental factor that indirectly affected ecosystem productivity by increasing the community weighted mean of plant maximum height, which simultaneously declined with species richness. The present study advances our understanding of the mechanisms driving variation in the productivity of temperate coastal saline meadows, providing evidence supporting the "mass ratio" hypothesis.

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