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1.
Environ Sci Technol ; 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31891257

RESUMO

Nitrate-N in wastewaters is hard to be recovered because it is difficult to volatilize with an opposite charge to ammonium. Here, we have proved the feasibility of dissimilatory nitrate reduction to ammonia (DNRA) by the easy-acclimated mixed electroactive bacteria, achieving the highest DNRA efficiency of 44%. It was then coupled with microbial electrolysis to concentrate ammonium by a factor of 4 in the catholyte for recovery. The abundance of electroactive bacteria in the biofilm before nitrate addition, especially Geobacter spp., was found to determine the DNRA efficiency. As the main competitors of DNRA bacteria, the growth of denitrifiers was more sensitive to C/N ratios. The DNRA microbial community contrarily showed a stable and recoverable ammoniation performance over C/N ratios ranging from 0.5 to 8.0. A strong competition of the electrode and nitrate on electron donors was observed at the early stage (15 d) of electroactive biofilm formation, which can be weakened when the biofilm was mature on 40 d. Quantitative PCR showed a significant increase in nirS and nrfA transcripts in the ammoniation process. nirS was inhibited significantly after nitrate depletion while nrfA was still upregulated. These findings provided a novel way to recover nitrate-N using organic wastes as both electron donor and power, which has broader implications on the sustainable wastewater treatment and the ecology of nitrogen cycling.

2.
J Phys Chem Lett ; 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31912740

RESUMO

Mechanoresponsive luminescent materials have attracted widespread attention for their potential applications, especially for these behaving pressure-induced emission enhancement (PIEE). Designing and seeking for systems with high-efficiency PIEE is desirable and crucial for material science. Here, the mechanism of different piezo-responsive luminescence of 2,3,4,5-tetraphenylthiophene (TPT) and 2,3,4,5-tetraphenylfuran (TPF) crystals are explored. The experimental results combined DFT theory calculation indicated that PIEE phenomenon is possibly exhibited in V-shape arrangement for the reason of the weak π-π interactions. This study not only gains deep insight into the relationship between optical properties and structural evolution, but also puts forward a strategy for designing PIEE materials from the point of molecular arrangement.

3.
Nanoscale ; 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31912845

RESUMO

Halide perovskites have attracted great attention owing to their outstanding performance in optoelectronic applications and solar cells. Recently, two-dimensional (2D) Cs3Sb2I9 nanocrystals (NCs) have attracted sustained interest due to their potentially useful photovoltaic behavior. However, their practical application is impeded by the large bandgap. In this study, the bandgap of 2D Cs3Sb2I9 NCs is successfully narrowed from 2.05 eV to 1.36 eV by means of a high pressure with a measurable rate of 33.7%. Optical changes of 2D Cs3Sb2I9 NCs originate from Sb-I bond contraction and I-Sb-I bond angle changes within the [SbI6]3- octahedra, which determines the overlap of orbitals. Angle dispersive synchrotron X-ray diffraction spectra and Raman spectra of Cs3Sb2I9 NCs indicate that the structural amorphization gradually begins at about 14.0 GPa and the changes are reversible once pressure is completely released. The band gap is slightly smaller after decompression than that under the initial ambient conditions, resulting from the incomplete recrystallization process. First-principles calculations further elucidate that variations in band gaps are mainly governed by the orbital interactions associated with the distortion of the Sb-I octahedral network upon compression. The research enhances the fundamental understanding of 2D Cs3Sb2I9 NCs and is expected to greatly advance the research progress of perovskites in band gap interception at high pressures. Meanwhile, this study demonstrates that pressure processing can be used as a robust strategy to improve materials-by-design in applications.

5.
Huan Jing Ke Xue ; 41(1): 460-468, 2020 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854949

RESUMO

The effects of a single application of three amendments (biochar, lignite, and chicken manure) on the fraction transformations of soil Cd and Ni and uptake by winter wheat are reported to provide reference for passivation and the remediation of heavy metals in soil. Field experiments were conducted to investigate the effects of different passivators on the forms of Cd and Ni in soils at different growth stages of winter wheat, and to analyze the contents of Cd and Ni in different organs of wheat. The results showed that biochar increased soil pH and that lignite reduced soil pH, but not significantly. Chicken manure significantly reduced soil pH at booting and mature stages, and decreased by 0.23 and 0.20 pH units, respectively. The single application of biochar, chicken manure, or lignite did not reduce the exchangeable Ni content significantly, whereas the effect on the exchangeable Cd was significant. Lignite 2% treatment had the greatest decrease in exchangeable Cd at different growth stages of wheat, which were 30.50%, 43.34%, and 31.20%, respectively. The contents of Cd and Ni in the shoots and underground parts of wheat decreased to some extent, and the extent of these decreases increased with the increase of passivator dosage. The decrease of Cd content in wheat roots was the largest under the treatment of lignite 2% at different growth stages, reaching 38.35%, 58.00%, and 50.20% respectively. The greatest decline of Ni content in wheat roots occurred in the lignite 2% treatment at the booting (41.33% decline) and mature stages (51.35%). All the three amendments reduced the availability of Cd and Ni in slightly alkaline soil, and the passivation effect on Cd was better than that of Ni. All three amendments also effectively reduced the content of Cd and Ni in different organs of wheat plants in different growth period. The order of decreasing effect of Cd in wheat organs was lignite > biochar > chicken manure at the same dose of these three passivators.

6.
RNA Biol ; : 1-14, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31885317

RESUMO

Emerging evidence has suggested that long noncoding RNAs (lncRNAs) play an essential role in the tumorigenesis of multiple types of cancer including gastric cancer (GC). However, the potential biological roles and regulatory mechanisms of lncRNA in response to cisplatin, which may be involved in cisplatin resistance, have not been fully elucidated. In this study, we identified a novel lncRNA, cisplatin resistance-associated lncRNA (CRAL), that was downregulated in cisplatin-resistant GC cells, impaired cisplatin-induced DNA damage and cell apoptosis and thus contributed to cisplatin resistance in GC cells. Furthermore, the results indicated that CRAL mainly resided in the cytoplasm and could sponge endogenous miR-505 to upregulate cylindromatosis (CYLD) expression, which further suppressed AKT activation and led to an increase in the sensitivity of gastric cancer cells to cisplatin in vitro and in preclinical models. Moreover, a specific small molecule inhibitor of AKT activation, MK2206, effectively reversed the cisplatin resistance in GC caused by CRAL deficiency. In conclusion, we provide the first evidence that a novel lncRNA, CRAL, could function as a competing endogenous RNA (ceRNA) to reverse GC cisplatin resistance via the miR-505/CYLD/AKT axis, which suggests that CRAL could be considered a potential predictive biomarker and therapeutic target for cisplatin resistance in gastric cancer.

7.
J Dairy Sci ; 103(1): 87-97, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31677844

RESUMO

Previous research reported that fermented yak milk had a diverse microbial composition. For this study, raw yak milk, qula, and fermented yak milk samples were collected from the Aba Tibetan autonomous region of China. The genus and species microbial composition of these samples were analyzed by high-throughput sequencing of 16S rRNA and groEL gene amplicons, and the volatile profile of the samples was quantified by gas chromatography-mass spectrometry. The results indicated variation in abundance of microbiota at the genus level among the fermented yak milk samples, with Lactobacillus as the most abundant genus in the majority of samples, ranging from 41.6 to 98.3%. The volatile profile of the samples varied among those collected from different villages. Correlations between bacterial composition and volatile compounds of the samples were also observed. Lactobacillus displayed a significant correlation with volatile compounds such as benzaldehyde, 2,3-pentanedione, ethanol, and ethyl acetate, whereas the samples with relatively high abundance of Streptococcus and Lactococcus displayed relatively low contents of volatile compounds.

8.
J Dairy Sci ; 103(1): 166-171, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31704010

RESUMO

The ability to use lactose is critical for the application of Streptococcus thermophilus in fermented dairy products. Most studies have evaluated the use of lactose of S. thermophilus by measuring lactose utilization, but its correlation with ß-galactosidase and urease has rarely been investigated. In this study, 10 strains of S. thermophilus isolated from fermented yak milk exhibited a diversity of ß-galactosidase and urease activities, growth, and acid production in de Man, Rogosa, and Sharpe-lactose. Among the strains, 15G5 possessed the highest ß-galactosidase activity and showed the highest cell growth, lactic acid production, and titratable acidity during fermentation. In contrast, 7G10, with the weakest ß-galactosidase activity, produced the lowest lactic acid content and change in titratable acidity. Further investigation indicated that ß-galactosidase activity of S. thermophilus showed significant positive correlations with the growth of cell densities, the production of lactic acid, and titratable acidity, and urease activity of S. thermophilus showed a significant correlation with the use of lactose and the production of lactic acid and acetaldehyde. These findings suggest that the differences of ß-galactosidase and urease activities are essential for the performance in the lactose metabolism, growth, and acid production of S. thermophilus, providing new insights into strain selection and application.

9.
Artigo em Inglês | MEDLINE | ID: mdl-31831444

RESUMO

This article deals with the recursive filtering issue for a class of nonlinear complex networks (CNs) with switching topologies, random sensor failures and dynamic event-triggered mechanisms. A Markov chain is utilized to characterize the switching behavior of the network topology. The phenomenon of sensor failures occurs in a random way governed by a set of stochastic variables obeying certain probability distributions. In order to save communication cost, a dynamic event-triggered transmission protocol is introduced into the transmission channel from the sensors to the recursive filters. The objective of the addressed problem is to design a set of dynamic event-triggered filters for the underlying CN with a certain guaranteed upper bound (on the filtering error covariance) that is then locally minimized. By employing the induction method, an upper bound is first obtained on the filtering error covariance and subsequently minimized by properly designing the filter parameters. Finally, a simulation example is provided to demonstrate the effectiveness of the proposed filtering scheme.

10.
Clin Cancer Res ; 2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31831555

RESUMO

PURPOSE: Long non-coding RNAs (lncRNAs) has been observed in various cancer types. Our bioinformatic analysis of existing database demonstrated overexpression of lncRNA THAP9-AS1 in pancreatic ductal adenocarcinoma (PDAC). We aimed to investigate the roles and mechanisms of THAP9-AS1 in PDAC. EXPERIMENTAL DESIGN: The overexpression of THAP9-AS1 in samples of pancreatic cancer patients was characterized and was associated with clinical outcomes. The non-protein coding property of the THAP9-AS1 was verified. Various in vitro and in vivo experiments were performed to investigate the interaction between THAP9-AS1 and YAP signaling. RESULTS: We demonstrated that lncRNA THAP9-AS1 is overexpressed in PDAC in multiple patient sample sets, which is significantly associated with poor outcome of PDAC patients. THAP9-AS1 promotes PDAC cells growth both in vitro and in vivo THAP9-AS1 exerts its effects via enhancing YAP signaling. Ectopic YAP expression overcame the effects of THAP9-AS1 knockdown. Inversely, YAP knockdown diminished the effects of THAP9-AS1 overexpression. THAP9-AS1 acts as a competing endogenous RNA for miR-484, leading to YAP upregulation. Moreover, THAP9-AS1 binds to YAP protein and inhibits the phosphorylation mediated inactivation of YAP by LATS1. Reciprocally, YAP/TEAD1 complex promotes THAP9-AS1 transcription to form a feed-forward circuit. Importantly, THAP9-AS1 level positively correlates with YAP expression in PDAC tissues. YAP overexpression also predicts a poor outcome of PDAC patients. CONCLUSIONS: Our findings indicate that THAP9-AS1 plays an important role in PDAC growth via enhancing YAP signaling which in return also modulates THAP9-AS1 transcription. THAP9-AS1/YAP axis may serve as a potential biomarker and therapeutic target for PDAC treatment.

11.
Artigo em Inglês | MEDLINE | ID: mdl-31832959

RESUMO

In recent years, countries both developed and developing ones have experienced a rapid economic globalization expanding economic activities. Although this economic globalization process is fruitful for the economy; however, what role it plays in the promotion of the human development index is still unknown. To this end, the study tries to explore the linkage among economic globalization, real income, and human development index in Asian countries from 1990 to 2015. The advanced econometric techniques that allow dependencies across countries are employed. The panel cointegration approach, Westerlund (2007) panel cointegration test, confirms the cointegration relationship among study variables, and the study estimates long-run cointegration parameters. Results reveal that economic globalization has not a significant impact on human development. However, real income promotes human development in Asian countries.

12.
Ying Yong Sheng Tai Xue Bao ; 30(12): 4169-4176, 2019 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-31840462

RESUMO

We investigated the effects of different drip irrigation quotas on leaf area index (LAI), diffuse non-interceptance (DIFN), light interception rate (LIR), canopy apparent photosynthetic rate (CAP), and cotton yield of Xinluzao 45 in field of north Xinjiang. There were five drip irrigation treatments, i.e. W1: 600 m3·hm-2, W2: 540 m3·hm-2, W3: 480 m3·hm-2, W4: 420 m3·hm-2, W5: 360 m3·hm-2. The results showed that with the decrease in drip irrigation quota, LAI, LIR and CAP of cotton substantially decreased, with the difference between W1 and W2 being not statistically significant from the full squaring to boll opening stage. Moreover, DIFN was enhanced with the reduction in drip irrigation quota. Highest seed and lint yield (6549 kg·hm-2 and 2677 kg·hm-2, respectively) presented in W1. W2 got a 6.5% reduction of seed cotton yield compared with W1, but the irrigation water use efficiency was enhanced by 3.9%. LAI, LIR and CAP were positively correlated with seed cotton yield from full flowering stage to full boll stage. Therefore, drip irrigation quota at 540 m3·hm-2 could increase irrigation water use efficiency, maintain higher leaf area index, increase diffuse non-interceptance, and ensure light interception rate from full flowering stage to full boll stage, which could enhance canopy apparent photosynthetic rate and water use efficiency without sacrificing yield.

13.
Materials (Basel) ; 12(23)2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31816839

RESUMO

In order to match the solid food oxidation during logistics and storage process under severe high temperature, a double-switch temperature-sensitive controlled release antioxidant film embedded with lyophilized nanoliposomes encapsulating rosemary essential oils (REOs) was prepared. The double switch temperature at 35.26 and 56.98 °C was achieved by development of a temperature sensitive polyurethane (TSPU) film. With biaxially oriented polyethylene terephthalate (BOPET) as a barrier layer, the intelligent complex film was prepared via coating the TSPU embedded with lyophilized nanoliposomes encapsulating REOs on BOPET. The results indicate that the REO is well encapsulated in nanoliposomes with encapsulation efficiency (EE) of 67.3%, high stability and lasting antioxidant effect during 60 days. The incorporation of lyophilized nanoliposomes containing REOs into TSPU remains the double-switch temperature-sensitive characteristic of the prepared TSPU. In agreement with porosity and WVTR results, the diffusion coefficient (D) of the antioxidant complex film sharply increases respectively at two switching temperatures, indicating that the intelligent double-switch temperature-sensitive controlled release property is functioning. Furthermore, compared with films directly added with REO, the lower Ds of films added with lyophilized nanoliposomes encapsulating REOs provides a longer-lasting antioxidant activity. Thus, the acquired controlled release antioxidant film sensitive to temperature at 39.56 and 56.00 °C can be potentially applied for protection of solid food during distribution and storage process under severe high temperatures.

14.
Artigo em Inglês | MEDLINE | ID: mdl-31817089

RESUMO

In recent years, the increasing rate of road crashes involving cyclists with a disproportionate overrepresentation in injury statistics has become a major concern in road safety and public health. However, much remains unknown about factors contributing to cyclists' high crash rates, especially those related to personal characteristics. This study aims to explore the influence of cyclist personality traits and cycling behaviors on their road safety outcomes using a mediated model combining these constructs. A total of 628 cyclists completed an online questionnaire consisting of questions related to cycling anger, impulsiveness, normlessness, sensation seeking, risky cycling behaviors, and involvement in crash-related conditions in the past year. After the psychometric properties of the employed scales were examined, the relationships among the tested constructs were investigated using structural equation modeling. The results showed that cyclists' crash risks were directly predicted by risky cycling behaviors and cycling anger, and the effects of cycling anger, impulsiveness, as well as normlessness on crash risks, were mediated by cycling behaviors. The current findings provide insight into the importance of personality traits in impacting cycling safety and could facilitate the development of evidence-based prevention and promotion strategies targeting cyclists in China.

15.
Cancer Manag Res ; 11: 9843-9848, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31819621

RESUMO

Background: The objective of this study was to evaluate the efficiency and safety of microwave thermal ablation in the treatment of skip metastases in extremity osteosarcomas. Osteosarcoma of extremities with skip metastases has a poor prognosis, and thus, microwave thermal ablation presents an attractive minimally invasive option in this patient group. Methods: A retrospective review included a cohort of 76 patients with extremity osteosarcoma in one institute, of which five cases (6.6%) showed skip metastases. Skip lesions located in proximal femur and primary sites were distal femur in all five patients. The authors treated skip lesions using microwave thermal ablation after primary tumors were removed at wide margins. Procedural efficacy and safety were determined with postoperative MSTS score and follow-ups of 12-62 months (median 22 months). Results: The ablation time was five to nine minutes (mean seven minutes). Taking advantage of Microwave-induced hyperthermia, wide resections of distal femur and endoprosthesis reconstructions were performed instead of total femoral resection and replacement in four patients, and above-knee amputation was performed instead of hip disarticulation in one patient. The postoperative hip functions were intact and the mean lower extremity MSTS score was 26. Three patients died at 12-22 months after definitive surgery because of pulmonary metastases, and two patients remained disease-free at 44 and 62 months after surgery, respectively. No local recurrence either at sites of primary tumors or skip lesions was found at time of the latest follow up. Conclusion: Microwave thermal ablation is efficacious in treating skip metastases of osteosarcoma in extremities. The modality has promise for good local control of tumors, less invasive surgeries, and intact and satisfied lower extremity functions in these relatively poor prognosis patients. Level of evidence: Therapeutic Level III.

16.
J Agric Food Chem ; 2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31822063

RESUMO

Enzymatic production of xylitol is a promising alternative to the chemical hydrogenation process. However, it encounters problems that are largely due to protein susceptibility to environmental factors. In this study, to develop a robust, practical enzymatic process for xylitol production, a coupled enzyme system consisting of formate dehydrogenase (FDH), glucose dehydrogenase (GDH), and xylose reductase (XR) was constructed, wherein the alkaline product produced by FDH and the acidic product produced by GDH could neutralize each other during cofactor regeneration. After optimization of conditions, a pH-neutralization, redox-balanced process was developed that could be carried out in pure water requiring no pH regulation. As a result, a xylitol production of 273.6 g/L that is much higher than those yet reported was obtained from 2 M xylose in 24 hours, with a relatively high productivity of 11.4 g/L/h. The strategy demonstrated here can be adapted for production of other NADH-consuming products.

17.
Sci Total Environ ; : 135690, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31784166

RESUMO

Wastewater is widely recognized as a sink of active nitrogen and phosphorus, and the recovery of both nutrients as fertilizers is widely studied in recent years. Electroactive bacteria increasingly attract attentions in this area because they are able to produce an electric field in microbial electrochemical systems to concentrate ammonium and phosphate for recovery. Importantly, these unique bacteria are able to convert nitrate and nitrite directly to ammonium, maximizing the active nitrogen species capable of recovery. Ferric ions produced by electroactive bacteria can be precipitated with phosphate to recover as vivianite in neutral wastewaters. All these processes employed electroactive bacteria as both nitrate and iron reducer and bioelectric field generator. The mechanism as well as technologies are summarized, and the challenges to further improve their performance are discussed.

19.
J Therm Biol ; 86: 102451, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31789239

RESUMO

The aim of this study was to investigate the physiological and perceptual responses of the human body wearing stab-resistant body armor (SRBA) in a hot and humid environment. The responses of five healthy male volunteers wearing SRBA were compared with those under a Control condition (wearing T-shirt) in a hot and humid environment (38 °C and relative humidity of 60%). The participants walked on a treadmill at a speed of 6 km/h for 60 min and this was followed by 60 min of recovery. The physiological responses (core temperature, skin temperature, heart rate, oxygen consumption) and perceptual parameters (thermal sensation, thermal comfort, rate of perceived exertion (RPE), and restriction to movement) were recorded throughout the tests. The results showed that the use of SRBA resulted in higher values of core temperature, mean skin temperature, heart rate, and oxygen consumption during exercise, and a significant difference (p < 0.05) between the SRBA and Control trials in terms of oxygen consumption was observed. The subjects wearing SRBA exhibited higher RPE and restriction to movement during exercise when compared with those in the Control condition, and a significant difference (p < 0.05) between the two trials in terms of restriction to movement was observed. Moreover, no significant differences (p > 0.05) in terms of thermal sensation and thermal comfort were observed between the SRBA and Control trials. It was concluded that the use of SRBA imposed high thermoregulatory and cardiovascular strain, reduced perceived exertion, and restricted movement during exercise in the hot and humid environment, whereas its effect on thermal sensation and thermal comfort was negligible when compared with those in the Control condition.

20.
Artigo em Inglês | MEDLINE | ID: mdl-31790190

RESUMO

Perovskites have become important OER electrocatalysts. Herein, as-prepared La0.8Sr0.2Co0.8Fe0.2O3-δ (LSCF-0) is chosen as a sample to exhibit the superimposed effect of surface reconstruction accompanied by reduction of Co3+ to Co2+ on the further improvement of its activity and stability. As-synthesized LSCF-0 perovskite is chemically treated by simply immersing in an aqueous solution of NaBH4 for 1.0 h at room temperature. The optimized LSCF (LSCF-2) owns an amorphous layer consisting of nanosized particles of ∼20 nm (vs smooth bulk crystalline surface for untreated LSCF), which exhibits superior OER performance to LSCF-0. LSCF-2 has an overpotential of 248 mV (10 mA cm-2) and a Tafel slope of 51 mV dec-1 (vs 355 mV and 76 mV dec-1 for LSCF-0 and 381 mV and 91 mV dec-1 for LCO) and an excellent cycle stability for 20 h running. This work supplies a new strategy to enhance OER performance through surface reconstruction of as-prepared perovskites.

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