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1.
ACS Nano ; 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-32003558

RESUMO

A two-dimensional topological insulator features (only) one bulk gap with nontrivial topology, which protects one-dimensional boundary states at the Fermi level. We find a quantum phase of matter beyond this category: a multiple topological insulator. It possesses a ladder of topological gaps; each gap protects a robust edge state. We prove a monolayer of van der Waals material PtBi2 as a two-dimensional multiple topological insulator. By means of scanning tunneling spectroscopy, we directly visualize the one-dimensional hot electron (and hole) channels with nanometer size on the samples. Furthermore, we confirm the topological protection of these channels by directly demonstrating their robustness to variations of crystal orientation, edge geometry, and sample temperature. The discovered topological hot electron materials may be applied as efficient photocatalysts in the future.

2.
J Chem Phys ; 152(4): 044105, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32007075

RESUMO

The Bethe-Salpeter equation (BSE) based on GW quasiparticle levels is a successful approach for calculating the optical gaps and spectra of solids and also for predicting the neutral excitations of small molecules. We here present an all-electron implementation of the GW+BSE formalism for molecules, using numeric atom-centered orbital (NAO) basis sets. We present benchmarks for low-lying excitation energies for a set of small organic molecules, denoted in the literature as "Thiel's set." Literature reference data based on Gaussian-type orbitals are reproduced to about one millielectron-volt precision for the molecular benchmark set, when using the same GW quasiparticle energies and basis sets as the input to the BSE calculations. For valence correlation consistent NAO basis sets, as well as for standard NAO basis sets for ground state density-functional theory with extended augmentation functions, we demonstrate excellent convergence of the predicted low-lying excitations to the complete basis set limit. A simple and affordable augmented NAO basis set denoted "tier2+aug2" is recommended as a particularly efficient formulation for production calculations. We finally demonstrate that the same convergence properties also apply to linear-response time-dependent density functional theory within the NAO formalism.

3.
Sci Total Environ ; 705: 135774, 2020 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-31972934

RESUMO

Soil moisture (SM) is a key variable in the climate system as it regulates the latent and sensible heat partition and influences eco-hydrological processes. A few studies have highlighted the increasing frequency of SM droughts at the river basin scale in China, however, little is known about the SM response to precipitation (P) and near-surface temperature (T) at national and regional scales. In this study, the long-term SM dynamics based on a sophisticated land surface hydrological model (i.e., the Variable Infiltration Capacity, VIC) were identified after model evaluation. A simple but effective sensitivity-based approach was developed to quantify the elasticity (ε) and sensitivity (S) of SM to P and T, and the SM was projected for the near future at the regional scale. The results indicate that China has experienced slightly wetter soil conditions during the past five decades and the SM has increased in the arid and semi-arid regions of China, i.e., the North East (0.11 mm/yr) and the North West (0.047 mm/yr). The elasticity and the sensitivity of SM are the highest in the humid region (i.e., South East China), indicating that small increases of P and T are likely to induce considerable changes in the SM relative to other regions. The sensitivity-based approach could perform SM estimation similar to the complex VIC modeling. This approach projected that North China (-5.05 ± 2.31%) and South West China (-5.95 ± 2.04%) are likely to experience drying with a considerable decline in SM due to reduction in P and rise in T in the near future period from 2020 to 2050. The slightly wet soil conditions in the past and a drying future scenario may imply a contrasting consequence for the regional-scale hydrological cycles.

6.
J Org Chem ; 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-31958946

RESUMO

An approach for the construction of furo[3,2-b]quinolines and furo[2,3-b:4,5-b']diquinolines is developed through a metal-free [4 + 2] cycloaddition of easily available in situ generated aza-o-quinone methides and furans. The reaction tolerates a wide range of aza-o-quinone methides and substituted furans to afford the corresponding dihydro- or tetrahydrofuroquinolines in good to excellent yields. Mechanistic studies reveal that the reaction involves a concerted [4 + 2] cycloaddition pathway and shows a high regioselectivity of cycloaddition for a furan ring. The present method features mild reaction conditions, dearomatization of furans, high regio- and diastereoselectivity, gram-scalable preparations, and diversity of furoquinolines.

7.
Brain ; 143(2): 570-581, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31953931

RESUMO

At least 50% of patients with tuberous sclerosis complex present with intractable epilepsy; for these patients, resective surgery is a treatment option. Here, we report a nationwide multicentre retrospective study and analyse the long-term seizure and neuropsychological outcomes of epilepsy surgery in patients with tuberous sclerosis complex. There were 364 patients who underwent epilepsy surgery in the study. Patients' clinical data, postoperative seizure outcomes at 1-, 4-, and 10-year follow-ups, preoperative and postoperative intelligence quotients, and quality of life at 1-year follow-up were collected. The patients' ages at surgery were 10.35 ± 7.70 years (range: 0.5-47). The percentage of postoperative seizure freedom was 71% (258/364) at 1-year, 60% (118/196) at 4-year, and 51% (36/71) at 10-year follow-up. Influence factors of postoperative seizure freedom were the total removal of epileptogenic tubers and the presence of outstanding tuber on MRI at 1- and 4-year follow-ups. Furthermore, monthly seizure (versus daily seizure) was also a positive influence factor for postoperative seizure freedom at 1-year follow-up. The presence of an outstanding tuber on MRI was the only factor influencing seizure freedom at 10-year follow-up. Postoperative quality of life and intelligence quotient improvements were found in 43% (112/262) and 28% (67/242) of patients, respectively. Influence factors of postoperative quality of life and intelligence quotient improvement were postoperative seizure freedom and preoperative low intelligence quotient. The percentage of seizure freedom in the tuberectomy group was significantly lower compared to the tuberectomy plus and lobectomy groups at 1- and 4-year follow-ups. In conclusion, this study, the largest nationwide multi-centre study on resective epilepsy surgery, resulted in improved seizure outcomes and quality of life and intelligence quotient improvements in patients with tuberous sclerosis complex. Seizure freedom was often achieved in patients with an outstanding tuber on MRI, total removal of epileptogenic tubers, and tuberectomy plus. Quality of life and intelligence quotient improvements were frequently observed in patients with postoperative seizure freedom and preoperative low intelligence quotient.

8.
Environ Pollut ; 256: 113294, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31679877

RESUMO

A novel denitrifying bacterium YSF15 was isolated from the Lijiahe Reservoir in Xi'an and identified as Comamonas sp. It exhibited excellent nitrogen removal ability under low C/N conditions (C/N = 2.5) and 94.01% of nitrate was removed in 18 h, with no accumulation of nitrite. PCR amplification and nitrogen balance experiments were carried out, showing that 68.92% of initial nitrogen was removed as gas products and the nitrogen removal path was determined to be NO3--N→NO2--N→NO→N2O→N2. Scanning electron microscopy and three-dimensional fluorescence spectroscopy were used to track extracellular polymeric substances (EPS). The results show that complete-denitrification under low C/N conditions is associated with EPS, which may provide a reserve carbon source in extreme environments. These findings reveal that Comamonas sp. YSF15 can provide novel basic materials and a theoretical basis for wastewater bioremediation under low C/N conditions.

9.
Nutr Metab Cardiovasc Dis ; 30(2): 265-273, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-31740238

RESUMO

BACKGROUND AND AIMS: The association between lipoprotein(a) [Lp(a)] levels and the risk of cardiovascular disease is of great interest but still controversial. This study sought to investigate the impact of Lp(a) on coronary severity and long-term outcomes of patients who undergo percutaneous coronary intervention (PCI). METHODS AND RESULTS: A total of 6714 consecutive patients who received PCI were enrolled to analyze the association between Lp(a) and coronary severity and major adverse cardiovascular and cerebrovascular events (MACCE). Patients were divided into tertiles according to Lp(a) levels on admission. Coronary severity was evaluated by SYNTAX scoring system. The MACCE included recurrent myocardial infarction, unplanned target vessel revascularization, stent thrombosis, ischemic stroke and all-cause mortality. Significantly, Lp(a) levels were positively associated with coronary severity (p < 0.001). Multivariate logistic regression analyses showed Lp(a) was an independent predictor of intermediate to high SYNTAX score. During an average of 874 days follow-up, 755 patients presented with MACCE (11.25%) were reported. The incidence rates of MACCE, all-cause mortality, cardiac death, target vessel revascularization, recurrent myocardial infarction, stent thrombosis, stroke and bleeding were not statistically different among the Lp(a) tertile groups. Furthermore, both Kaplan-Meier and Cox regression analyses found no relationship between Lp(a) and cardiovascular outcomes (p > 0.05). CONCLUSION: Lp(a) is an independent predictor of the prevalence of more complex coronary artery lesions (SYNTAX score ≥ 23) in patients with PCI. In addition, our study has shown that Lp(a) has no relationship with long-term cardiovascular outcomes in Chinese patients with PCI.

10.
Shock ; 53(2): 217-222, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30998645

RESUMO

OBJECTIVE: The aim of this study was to investigate the changes of bile acids in the liver during hemorrhagic shock (HS) and their potential to attenuate liver injury via activation of SIRT1 (sirtuin 1)-FXR (farnesoid X receptor) signaling. METHODS: A Sprague-Dawley (SD) rat HS model was established, whereas HepG2 cells were hypoxically cultured to simulate HS in vitro. Liver bile acids (BA) were profiled with ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). FXR expression was detected by western blot and immunohistochemistry. The mRNA levels of SIRT1 and FXR were detected by polymerase chain reaction. Protein expression of SIRT1, FoxM1, NF-κB, acetyl-NF-κB, p53, and acetyl-p53 was analyzed by western blot. Hepatocyte apoptosis and proliferation were measured by TUNEL assay and Ki-67 staining, respectively. Serum and supernatant cytokines were analyzed using ELISA assays. Liver injury was also assessed. To investigate the possible mechanisms, SIRT1 agonist (SRT1720), SIRT1 inhibitor (EX527), and FXR inhibitor (Z-guggulsterone) were used. RESULTS: Tauroursodeoxycholic acid (TUDCA) in the liver decreased significantly after HS. SIRT1 and FXR expression was time-dependently downregulated by HS or hypoxia condition. TUDCA upregulated SIRT1-FXR activity, which inhibited expression and acetylation of NF-κB and p53 and increased FoxM1 expression, leading to decreased inflammatory response and apoptosis and increased proliferative capacity in hepatocytes, and attenuation of liver injury. EX527 pretreatment reversed the protective effect of TUDCA. Moreover, Z-guggulsterone supplementation decreased the protective effect of TUDCA in vitro. CONCLUSION: TUDCA in the liver decreased during HS. TUDCA supplementation might attenuate HS-induced liver injury by upregulating SIRT1-FXR signaling.

11.
J Antimicrob Chemother ; 75(2): 309-317, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31702790

RESUMO

OBJECTIVES: Emergent antimicrobial-resistant hypervirulent Klebsiella pneumoniae (hvKp) is an important public health issue. We aimed to investigate resistance mechanisms and hypervirulent traits among tigecycline-non-susceptible (TNS) K. pneumoniae clinical strains, focusing on one hvKp strain with in vivo evolution of tigecycline resistance. METHODS: TNS K. pneumoniae strains causing invasive diseases in a medical centre in Taiwan between July 2015 and April 2018 were collected. Resistance mechanisms were determined and hvKp strains were defined as rmpA/rmpA2-carrying strains. Isogenic strains with and without tigecycline resistance were subjected to WGS and in vivo virulence testing. Further, site-directed mutagenesis was used to confirm the resistance mechanism. RESULTS: In total, 31 TNS K. pneumoniae strains were isolated, including six hypervirulent strains. Tigecycline resistance mechanisms were mostly caused by overexpression of AcrAB and OqxAB together with up-regulation of RamA or RarA, respectively. One TNS hypervirulent strain (KP1692; MIC=6 mg/L) derived from its tigecycline-susceptible counterpart (KP1677; MIC=0.75 mg/L) showed acrAB overexpression. WGS revealed four genetic variations between KP1677 and KP1692. In addition, using site-directed mutagenesis, we confirmed that a 1 bp insertion in the ramA upstream region (RamR-binding site), leading to ramA and acrAB overexpression in KP1692, was responsible for tigecycline resistance. The in vivo virulence experiment showed that the TNS hvKp strain KP1692 still retained its high virulence compared with KP1677. CONCLUSIONS: hvKp strains accounted for 19.4% among TNS strains. We identified alterations in the ramA upstream region as a mechanism of in vivo tigecycline resistance development in an hvKp strain.

12.
J Phys Chem Lett ; 11(1): 229-237, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31829604

RESUMO

Electronic stopping refers to the dynamical energy-transfer process to electrons in matter from highly energetic charged particles such as high-velocity protons. We discuss recent progress in theoretical studies of electronic stopping in condensed matter under ion irradiation, focusing on modern electronic structure theory's role in enabling the study of electronic excitation dynamics that result from the energy transfer. In the last few decades, first-principles simulation approaches based on real-time time-dependent density functional theory have greatly advanced the field. While linear response theory is widely used to study electronic stopping processes, especially for simple solids, novel first-principles dynamics approaches now allow us to study chemically complex systems and also yield detailed descriptions of electronic excitations at the molecular scale. Outstanding challenges for further advancement of electronic stopping modeling are also discussed from the viewpoint of electronic structure theory.

13.
Sci Total Environ ; 705: 135868, 2020 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-31818567

RESUMO

Global urban growth leads to a great increase in the impervious surface area (ISA) such as roads, plazas, airports, and parking lots, and consequently reshapes hydrological regimes in urban basins. Beijing, the capital of China, has experienced rapid urban growth since the 1980s. However, the spatial-temporal variability of the ISA and its impact on flooding risk are unclear. This study monitored urban growth (i.e., the evolution of the ISA) in Beijing for the period of 1980-2015 based on Landsat data, and identified the response of surface runoff yield using a land-surface hydrological model. The modeling at a relatively high spatial resolution (~6 km) was driven with retrieved long-term ISA dynamics, Global LAnd Surface Satellite (GLASS) product, and climate forcings. The results show that the impervious surface fraction (ISF) in Beijing increased from 8.73% (1448.16 km2) in 1980 to 22.22% (3685.92 km2) in 2015. With a demarcation at around the year 2000, the ISA growth presents a new pattern with a northeast-southwest direction from the Core Functional Zone (Core-Zone). Due to the ISA expansion, the simulated runoff coefficient in 2010 is approximately doubled compared to that of 1980. We identified an ISF threshold of approximately 6%, beyond which every 1% increase in the ISF may increase the surface runoff by approximately 5.51 mm/year, and thereby poses a high potential flooding risk even under a moderate rainfall event. In four typical historical storms, the sensitivity coefficients of surface runoff to precipitation and ISF were 0.97 and 0.63, respectively, indicating impervious surfaces dramatically enhanced the potential flooding risk. Our findings have implications for urban planning and the construction of sponge city in Beijing.

14.
J Cardiol ; 75(1): 60-65, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31416781

RESUMO

BACKGROUND: Inflammation plays a pivotal role in coronary artery disease (CAD). Few data from large-size studies are available on the association of high-sensitivity C-reactive protein (hs-CRP) and severity of CAD. Our aim was to investigate their relationship as well as their impact on long-term outcomes in patients undergoing percutaneous coronary intervention. METHODS: In 2013, 10,020 patients were consecutively included. Patients were divided into three groups based on hs-CRP on admission: 0-3mg/L (n=6978, 69.6%), 3.01-10mg/L (n=1997, 19.9%), >10mg/L (n=1045, 10.4%). Disease severity was determined by SYNTAX score (SS). Their differences were assessed in SS and major adverse cardiovascular events (MACEs, including all-cause death, myocardial infarction, revascularization, and in-stent thrombosis) among groups. RESULTS: The mean follow-up period was 874 days. Patients with elevated hs-CRP were older, had more risk factors such as hypertension, cerebrovascular disease, chronic obstructive pulmonary disease, and cigarette smoking. Multivariate regression analysis showed that hs-CRP >10mg/L (OR 1.49, 95% confidence interval 1.21-1.84, p<0.001), age, previous myocardial infarction, serum creatinine, and left ventricular ejection fraction were independent predictors of intermediate-high SS (>22). Subgroup analysis indicated that the relation between hs-CRP and SS was also consistent in acute coronary syndrome and its subtypes. Although elevated hs-CRP was positively associated with increased rates of MACEs (11.0% versus 12.1% versus 14.3%, p=0.006), death (1.0% versus 1.3% versus 3.0%, p<0.001), and revascularization (8.6% versus 10.4% versus 10.0%, p=0.032), it did not show any prognostic effect for adverse outcomes in multivariate regression analyses (all adjusted p> 0.05). While SS>22 remained independently predictive of MACEs and revascularization after adjusting confounders, the risks of which were increased by 56% and 68%, respectively. CONCLUSION: Serum hs-CRP could be a useful biomarker for indicating CAD severity and could aid in risk stratification.

15.
Front Neurosci ; 13: 1239, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31824244

RESUMO

Cognitive dysfunction is a very severe consequence of diabetes, but the underlying causes are still unclear. Recently, the cerebellum was reported to play an important role in learning and memory. Since long-term depression (LTD) is a primary cellular mechanism for cerebellar motor learning, we aimed to explore the role of cerebellar LTD pathways in diabetic rats and the therapeutic effect of gastrodin. Diabetes was induced by a single injection of streptozotocin into adult Sprague-Dawley rats. Motor learning ability was assessed by a beam walk test. Pathological changes of the cerebellum were assessed by Hematoxylin-Eosin (HE) and Nissl staining. Cellular apoptosis was assessed by anti-caspase-3 immunostaining. Protein expression levels of LTD pathway-related factors, including GluR2, protein kinase C (PKC), NR2A, and nNOS, in the cerebellar cortex were evaluated by western blotting and double immunofluorescence. The NO concentration was measured. The cellular degeneration and the apoptosis of Purkinje cells were evident in the cerebellum of diabetic rats. Protein expression levels of GluR2 (NC9W: 1.26 ± 0.12; DM9W + S: 0.81 ± 0.07), PKC (NC9W: 1.66 ± 0.10; DM9W + S: 0.58 ± 0.19), NR2A (NC9W: 1.40 ± 0.05; DM9W + S: 0.63 ± 0.06), nNOS (NC9W: 1.26 ± 0.12; DM9W + S: 0.68 ± 0.04), and NO (NC9W: 135.61 ± 31.91; DM9W + S: 64.06 ± 24.01) in the cerebellum were significantly decreased in diabetic rats. Following gastrodin intervention, the outcome of motor learning ability was significantly improved (NC9W: 6.70 ± 3.31; DM9W + S: 20.47 ± 9.43; DM9W + G: 16.04 ± 7.10). In addition, degeneration and apoptosis were ameliorated, and this was coupled with the elevation of the protein expression of the abovementioned biomarkers. Arising from the above, we concluded that gastrodin may contribute to the improvement of motor learning by protecting the LTD pathways in Purkinje cells.

16.
Int J Biol Macromol ; 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31794823

RESUMO

This study used response surface methodology to determine the optimal conditions for extraction of polysaccharides from Pyracantha. fortuneana (PSPF), and studied the mechanism of PSPF-inducing apoptosis in human ovarian carcinoma Skov3 cells. Response surface methodology (RSM) were adopted to extract PSPF. The maximum value of polysaccharide yield was obtained under these optimal conditions. PSPF had good potential as an antioxidant. Exposure of cells to PSPF resulted in cytotoxicity through the induction of apoptosis, and the reactive oxygen species were increased, mitochondrial membrane potential decreased, DNA damage (detected as γ- H2AX and RAD51 foci) was observed in Skov3 cells. In addition, PSPF could induce apoptosis of cancer cells. Therefore, PSPF should be explored as novel potential antioxidants and an anti-tumor drug in a clinical setting.

17.
Herz ; 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31807789

RESUMO

BACKGROUND: Since readmission rate is an important clinical index to determine the quality of inpatient care and hospital performance, the aim of this study was to explain the causes and predictors of readmission following transcatheter aortic valve implantation (TAVI) at short-term and mid-term follow-up. METHODS AND RESULTS: A systematic review and meta-analysis of all published articles from Embase, Pubmed/MEDLINE, and Ovid was carried out. In all, 10 studies including 52,702 patients were identified. The pooled estimate for the overall event rate was 0.15, and cardiovascular causes were the main reason for 30-day readmission (0.42, 95% confidence interval [CI]: 0.39-0.45). In addition, the pooled incidence of 1­year readmission was 0.31, and cardiovascular events were still the main cause (0.41, 95% CI: 0.33-0.48). Patients with major and life-threatening bleeding, new permanent pacemaker implantation, and clinical heart failure were associated with a high risk for early readmission after TAVI. Moreover, an advanced (≥3) New York Heart Association classification, acute kidney injury, paravalvular leak, mitral regurgitation (≥ moderate), and major bleeding predicted unfavorable outcome to 1­year readmission. Female gender and transfemoral TAVI was associated with a lower risk for unplanned rehospitalization. CONCLUSIONS: This meta-analysis found cardiovascular factors to be the main causes for both 30-day and 1­year rehospitalization. Heart failure represented the most common cardiovascular event at both short-term and mid-term follow-up. Several baseline characteristics and procedure-related factors were deemed unfavorable predictors of readmission. Importantly, transfemoral access and female gender were associated with a lower risk of readmission.

18.
Huan Jing Ke Xue ; 40(12): 5240-5249, 2019 Dec 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854594

RESUMO

The furniture manufacturing industry is a typical industry with high pollution, low added value, relatively outdated technology and low levels of pollution control. The process of furniture manufacturing uses a large number of paints and adhesives, which emit a great quantity of volatile organic compounds (VOCs). The furniture manufacturing industry is a key industry for the control of VOCs in China. The VOCs emission characteristics and environmental impact of the furniture manufacturing industry has been studied in this work, which could be helpful for the Chinese government when formulating VOCs pollution control policy for this industry. In this study, a typical furniture manufacturing enterprise was chosen as the object. The emission concentration level and source profile of VOCs in a typical enterprise was obtained, and an assessment of the environmental impact of furniture manufacturing was developed. The results showed that the concentration of VOCs in the workshop ranged from 9.18 to 181.58 mg·m-3, the concentration of VOCs in the stack was 30.64-155.94 mg·m-3, and the treatment efficiency was 7.43%-67.14%. The main species of VOCs in the workshop were aromatic hydrocarbons, esters, and aldehydes and ketones; the main species of VOCs in the stack are esters and aromatic hydrocarbons, followed by alkanes, and the main VOCs in the industry are sec-butyl acetate, toluene, m-xylene, methylal and ethylbenzene. The average ozone generation potential (OFP) of workshop and stack VOCs was 258.01 and 289.14 mg·m-3, respectively, and the average secondary organic aerosol generation potential (SOAFP) of workshop and stack VOCs was 148.66 and 165.31 mg·m-3, respectively. The most important contribution to the OFP and SOAFP in each emission sector is aromatic hydrocarbons. The OFP and SOAFP in the edge-sealing workshop are large and the VOCs should be controlled. The main malodorous substances at the shop boundary are sec-butyl acetate, m-xylene, butyl acetate, p-xylene, ethylbenzene, 1-ethyl-3-methylbenzene, o-xylene, and toluene; the VOCs at the factory boundary produce almost no odor pollution. Targeted enhanced control of aromatic hydrocarbons and esters should be adopted to achieve effective emission reduction of VOCs in furniture manufacturing.

19.
Huan Jing Ke Xue ; 40(8): 3463-3469, 2019 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854751

RESUMO

Based on the survey of 175 synthetic leather enterprises in Zhejiang Province, China, in 2014, this paper analyzes the control of volatile organic compounds (VOCs) and, ultimately, screened 161 key enterprises for further research. The results showed that most enterprises take measures to control waste gas; however, there is a distinct problem with the efficiency of exhaust gas collection. The industry used Solvent-based materials. The main VOC pollutants were DMF, toluene, methyl acetate, acetone, ethylacetate, and butanone. The VOC emission coefficient of the synthetic leather industry in Zhejiang was 0.168 kg·m-2. The industry includes polyurethane and polyvinyl chloride processes, for which VOC emission coefficients were 0.170 kg·m-2 and 0.142 kg·m-2, respectively. In addition, the emission coefficient of polyurethane wet processes was 0.191 kg·m-2 and that of dry processes was 0.179 kg·m-2. The emission coefficient for VOCs in post-treatment processes was 0.120 kg·m-2.

20.
PLoS Biol ; 17(12): e3000525, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31841517

RESUMO

Ubiquitin-specific protease (USP) 6 is a hominoid deubiquitinating enzyme previously implicated in intellectual disability and autism spectrum disorder. Although these findings link USP6 to higher brain function, potential roles for USP6 in cognition have not been investigated. Here, we report that USP6 is highly expressed in induced human neurons and that neuron-specific expression of USP6 enhances learning and memory in a transgenic mouse model. Similarly, USP6 expression regulates N-methyl-D-aspartate-type glutamate receptor (NMDAR)-dependent long-term potentiation and long-term depression in USP6 transgenic mouse hippocampi. Proteomic characterization of transgenic USP6 mouse cortex reveals attenuated NMDAR ubiquitination, with concomitant elevation in NMDAR expression, stability, and cell surface distribution with USP6 overexpression. USP6 positively modulates GluN1 expression in transfected cells, and USP6 down-regulation impedes focal GluN1 distribution at postsynaptic densities and impairs synaptic function in neurons derived from human embryonic stem cells. Together, these results indicate that USP6 enhances NMDAR stability to promote synaptic function and cognition.

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