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1.
J Environ Manage ; 355: 120504, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38447513

RESUMO

Ammonia-oxidation process directly contribute to soil nitrous oxide (N2O) emissions in agricultural soils. However, taxonomy of the key nitrifiers (within ammonia oxidising bacteria (AOB), archaea (AOA) and complete ammonia oxidisers (comammox Nitrospira)) responsible for substantial N2O emissions in agricultural soils is unknown, as is their regulation by soil biotic and abiotic factors. In this study, cumulative N2O emissions, nitrification rates, abundance and community structure of nitrifiers were investigated in 16 agricultural soils from major crop production regions of China using microcosm experiments with amended nitrogen (N) supplemented or not with a nitrification inhibitor (nitrapyrin). Key nitrifier groups involved in N2O emissions were identified by comparative analyses of the different treatments, combining sequencing and random forest analyses. Soil cumulative N2O emissions significantly increased with soil pH in all agricultural soils. However, they decreased with soil organic carbon (SOC) in alkaline soils. Nitrapyrin significantly inhibited soil cumulative N2O emissions and AOB growth, with a significant inhibition of the AOB Nitrosospira cluster 3a.2 (D11) abundance. One Nitrosospira multiformis-like OTU phylotype (OTU34), which was classified within the AOB Nitrosospira cluster 3a.2 (D11), had the greatest importance on cumulative N2O emissions and its growth significantly depended on soil pH and SOC contents, with higher growth at high pH and low SOC conditions. Collectively, our results demonstrate that alkaline soils with low SOC contents have high N2O emissions, which were mainly driven by AOB Nitrosospira cluster 3a.2 (D11). Nitrapyrin can efficiently reduce nitrification-related N2O emissions by inhibiting the activity of AOB Nitrosospira cluster 3a.2 (D11). This study advances our understanding of key nitrifiers responsible for high N2O emissions in agricultural soils and their controlling factors, and provides vital knowledge for N2O emission mitigation in agricultural ecosystems.


Assuntos
Ecossistema , Solo , Solo/química , Amônia/química , Carbono , Oxirredução , Archaea , Nitrificação , Microbiologia do Solo
2.
Small ; 19(34): e2300801, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37072877

RESUMO

Sub-10 nm nanoparticles are known to exhibit extraordinary size-dependent properties for wide applications. Many approaches have been developed for synthesizing sub-10 nm inorganic nanoparticles, but the fabrication of sub-10 nm polymeric nanoparticles is still challenging. Here, a scalable, spontaneous confined nanoemulsification strategy that produces uniform sub-10 nm nanodroplets for template synthesis of sub-10 nm polymeric nanoparticles is proposed. This strategy introduces a high-concentration interfacial reaction to create overpopulated surfactants that are insoluble at the droplet surface. These overpopulated surfactants act as barriers, resulting in highly accumulated surfactants inside the droplet via a confined reaction. These surfactants exhibit significantly changed packing geometry, solubility, and interfacial activity to enhance the molecular-level impact on interfacial instability for creating sub-10 nm nanoemulsions via self-burst nanoemulsification. Using the nanodroplets as templates, the fabrication of uniform sub-10 nm polymeric nanoparticles, as small as 3.5 nm, made from biocompatible polymers and capable of efficient drug encapsulation is demonstrated. This work opens up brand-new opportunities to easily create sub-10 nm nanoemulsions and advanced ultrasmall functional nanoparticles.

3.
Macromol Rapid Commun ; 43(11): e2200127, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35334130

RESUMO

Biological polyampholytes are ubiquitous in living organisms with primary functions including serving as transporters for moving chemical molecular species across the cell membranes. Synthetic amphoteric macromolecules that can change their phase states depending on the environment to simulate some properties of natural polyampholytes are of great interest. Here, the implementation of synthetic pseudo polymeric ampholytes is explored with ion-recognition-triggered conformational change. The phase transition behaviors of the ion-recognition-creative polyampholytes that contain deprotonated carboxylic acid groups as negative charges and 18-crown-6 units for forming positively charged host-guest complexes are systematically investigated. The ion-recognition-triggered phase transition behaviors of pseudo polyampholytes significantly depend on cation species and concentrations. Only those specific ions such as K+ , Ba2+ , Sr2+ and Pb2+ ions that can form 1:1 host-guest complexes with 18-crown-6 units in polymers enable control over conformational change like that of traditional pH-dependent polyampholytes. By regulating the content of carboxylic acid groups to match the content of ion-recognized positive charges provided by the host-guest complexes, the pseudo polyampholytes are more sensitive to the recognizable cations. Such ion-recognition-triggered amphoteric characteristics make the pseudo polyampholytes act like biological proteins, nucleic acids, and enzymes as molecular transporters, genetic code storage, and biocatalysts in artificial systems.


Assuntos
Ácidos Carboxílicos , Polímeros , Íons/química , Conformação Molecular , Transição de Fase , Polímeros/química
4.
BMC Musculoskelet Disord ; 23(1): 192, 2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35236301

RESUMO

BACKGROUND: Though radiotherapy has been widely used for knee pigmented villonodular synovitis (PVNS), there is few literatures about radiotherapy for the treatment of PVNS hip. Thus, the purpose of this study was to analyze the clinical outcomes of endoscopic synovectomy with/without radiotherapy postoperatively of PVNS hip. METHODS: We performed a retrospective study of patients who underwent endoscopy in our hospital from November 2010 to January 2021. Inclusion criteria was patients with magnetic resonance image (MRI) signs, endoscopic findings and/or histological evidence of PVNS. Exclusion criteria was patients lost follow-up. All patients underwent synovectomy endoscopically and were divided into two groups depending on receiving postoperative radiotherapy or not. The primary outcome measurements were the recurrence of PVNS, receiving revision, and/or converting to total hip arthroplasty (THA). The secondary outcome measurements were the patient-reported outcome (PRO) collected at pre- and post-operation, which consist of Hip Outcome Score Activities of Daily Living (HOS-ADL), modified Harris Hip Score (mHHS), International Hip Outcome Tool-12 (IHOT-12), Non-arthritic Hip Scale (NAHS), and visual analog scale (VAS). RESULTS: In a case series of 16 patients (8 cases of male, 50%), 4 (25%) cases were localized type and 12 (75%) cases were diffuse type. The average follow-up was 44.8 ± 38.2 months (range,3 to 110). 8 (50%) cases (6 diffuse cases and 2 localized cases) received radiotherapy postoperatively, and the rest (6 diffuse cases and 2 localized cases) received endoscopic treatment alone. At the latest follow-up, 3 (18.75%) cases (2 diffuse cases and 1 localized case) who did not receive radiotherapy converted to arthroplasty. The preoperative HOS-ADL, mHHS, IHOT-12, NAHS, VAS scores of remaining 13 patients were 63.1 ± 19.1 (range,32.0 to 98.8), 54.8 ± 20.1 (range, 10.0 to 77.0), 50.9 ± 15.4 (range, 31.0 to 76.6),51.6 ± 15.9 (range, 20.0 to 84.4), 6.0 ± 1.4 (range,4.0 to 8.0) points, respectively. The latest HOS-ADL, mHHS, IHOT-12, NAHS, VAS scores of the 13 patients were 79.7 ± 10.8 (range, 58.0 to 97.6), 78.6 ± 9.1 (range,55.0 to 87.0), 74.7 ± 9.7 (range, 55.6 to 91.0), 78.9 ± 18.7 (range,20.0 to 92.5), 3.1 ± 1.2 (range,2.0 to 6.0) points respectively. CONCLUSION: Endoscopic synovectomy can achieve satisfactory PRO in PVNS hip patients. Besides, postoperative adjuvant radiotherapy can achieve higher hip survivability than synovectomy alone in this present study.


Assuntos
Sinovite Pigmentada Vilonodular , Atividades Cotidianas , Artroscopia/métodos , Endoscopia , Humanos , Masculino , Radioterapia Adjuvante , Estudos Retrospectivos , Sinovectomia/métodos , Sinovite Pigmentada Vilonodular/radioterapia , Sinovite Pigmentada Vilonodular/cirurgia , Resultado do Tratamento
5.
BMC Musculoskelet Disord ; 23(1): 1082, 2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36503498

RESUMO

BACKGROUND: Subspine impingement (SSI) does not have effective diagnostic criteria, especially in patients who also have femoroacetabular impingement (FAI). The classification of anterior inferior iliac spine (AIIS) morphology via three-dimensional CT is controversial. PURPOSE: To propose a method for ultrasound-guided AIIS injection as a way to diagnose SSI and evaluate the accuracy of radiography methods, including 3-D CT and MRI, as well as intraoperative findings. METHODS: Patients diagnosed with FAI between September 2020 and December 2021 were evaluated in this prospective study. Those who met the criteria were included in the ultrasound-guided AIIS injection test. Whether the pain was relieved after injection was recorded in the radiology report. Patients who experienced significant relief of the anterior groin pain (more than 50%) after the AIIS injection were considered positive responders. Among these patients, radiography materials, including AIIS morphology as measured by 3-D CT as well as superior capsular oedema on MRI, were compared. The presence of congestion or bruising on the capsule side of the labrum corresponding to the AIIS during hip arthroscopy was recorded. RESULTS: A total of 73 patients with FAI underwent the ultrasound-guided AIIS injection test. Prevalence rates of 13.70% (10/73), 58.90% (43/73), 23.29% (17/73) and 4.11% (3/73) were recorded for Type I, Type IIA, Type IIB and Type III AIISs, respectively. Thirty-six patients had positive responses to injection, and 37 patients had negative responses to injection. None of the patients with Type I, 23 (53.49%) patients with Type IIA, 11 (64.71%) patients with Type IIB and 2 (66.7%) patients with Type III AIISs had positive responses to the injection. A total of 57.14% of patients with Type II or Type III AIIS had positive responses to the injection. The proportions of patients with superior capsular oedema on MRI in the Type I, Type IIA, Type IIB, and Type III AIIS groups was 0, 30.23, 29.41 and 0%, respectively. Among non-Type I AIIS patients, those who reported positive responses to the injection had a higher incidence of superior capsular oedema (38.89% vs. 14.81%, P = 0.036), but they had no significant differences in the proportion of congestion or bruising of the labrum (47.22% vs. 37.04%, P = 0.419). The results showed that no pairs of methods-ultrasound-guided injection, MRI, and intraoperative findings-achieved good consistency (κ = 0.222, κ = 0.098 and κ = - 0.116). CONCLUSIONS: Radiographic methods including 3-D CT and MRI as well as the intraoperative findings of the labrum cannot be considered an accurate and reliable basis for the diagnosis and treatment of SSI in FAI patients. It is suggested that ultrasound-guided AIIS injections be combined with radiography to better diagnose SSI. LEVEL OF EVIDENCE: IV, case series.


Assuntos
Impacto Femoroacetabular , Humanos , Estudos Prospectivos , Estudos Retrospectivos , Impacto Femoroacetabular/cirurgia , Radiografia , Artroscopia/métodos , Dor , Articulação do Quadril/cirurgia
6.
Macromol Rapid Commun ; 42(15): e2100200, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34028919

RESUMO

Thermochromic poly(N-isopropyl acrylamide) (PNIPAM) photonic crystal gels based on 1D magnetically assembling colloidal nanocrystal clusters have attracted much attention due to its convenient preparation process, striking color response, and good mechanical strength. However, there remain challenges to broaden the thermochromic range and improve the sensitivity for their iridescent color display. Here, a PNIPAM photonic gel with wide thermochromic range and high sensitivity is prepared by using four-arm star poly(ethylene glycol) acrylamide (PEGAAm) as cross-linker at appropriately reduced magnetic field strength as well as cross-linker content. PEGAAm improves the homogeneity of the microstructure in PNIPAM photonic gel and thus maintains the structure colors at a wide temperature range from room temperature to 44 °C. The reduced magnetic field strength of 70 Gs and low cross-linker content (the molar ratio of monomer to cross-linker of 300:1) lead to a large initial lattice spacing of the photonic gel and thus wide diffraction wavelength migration of 194 nm. This optimized PNIPAM gel exhibits vivid iridescent colors from orange-red to indigo blue as temperature increases from 20 to 44 °C with satisfactory repeatability. Therefore, it may be an ideal candidate for temperature sensors and displays with utility and accuracy such as low-temperature burns.


Assuntos
Nanopartículas , Óptica e Fotônica , Géis , Fótons , Temperatura
7.
J Anim Breed Genet ; 138(1): 122-134, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32378263

RESUMO

Back and thigh skin of chickens showed significant differences in the thickness and the feather follicle density and size, which are important traits for slaughtered chickens' appearance. In the present study, global gene expression profiling was conducted in the back and thigh skin of chickens using Microarray technology. The results showed that 676 genes were differentially expressed between back and thigh skin. The expression of the differentially expressed genes (DEGs), including PPP1R3C, IGF1, PTCHD1, HOXB6, FGF9, CAMK4, SHH, BMP8B, FOXN1 and PTGER2, was validated by real-time quantitative polymerase chain reaction (RT-qPCR), and the results were consistent with microarray results. Functional analysis revealed that the DEGs were significantly involved in cell proliferation, differentiation, apoptosis, adhesion and transport process, and the pathways were significantly mapped into the ECM-receptor interaction, peroxisome, focal adhesion, Hedgehog and PPAR signalling pathways. Protein-protein interaction network analysis suggested that signalling pathways related to feathers morphogenesis and development, such as Wnt, FGF, MAPK, SHH and BMP signalling pathways, occupied important positions in the network. Genes involved in these signalling pathways and adhesion molecules might play a vital role in skin and feather follicle development. Further single nucleotide polymorphism (SNP) association analysis of Wnt3A showed that the AC genotype of SNP g.255361 C>A significantly increased the feather follicle density of thigh skin. Our findings may provide new insights on candidate genes and pathways related to skin and feather follicle formation of chickens.


Assuntos
Galinhas , Plumas , Animais , Galinhas/genética , Perfilação da Expressão Gênica/veterinária , Morfogênese , Pele
8.
Med Sci Monit ; 25: 6691-6701, 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31489957

RESUMO

BACKGROUND The small ubiquitin-like modifier 1 (SUMO1) and small ubiquitin-like modifier 1 pseudogene 3 (SUMO1P3) are long noncoding RNAs (lncRNAs). The prognostic significance of SUMO1 and SUMO1P3 expression in non-small cell lung cancer (NSCLC) remains unclear. This study aimed to use clinical, genetic, and survival data from the Cancer Genome Atlas (TCGA), to analyze the prognostic significance of SUMO1 and SUMO1P3 expression in the two main subtypes of NSCLC, lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC). MATERIAL AND METHODS Data were acquired from TCGA and in silico survival analysis was performed. SUMO1 and SUMO1P3 expression were compared between patients with LUAD and LUSC. Patient outcome was assessed as complete remission (CR), partial remission (PR), stable disease (SD), and progressive disease (PD). Recurrence-free survival (RFS) was defined as the survival time from primary surgery to the time of locoregional or distant recurrence of lung cancer. RESULTS SUMO1P3 was significantly increased in LUSC and LUAD tissues compared with adjacent normal lung tissue and was significantly co-expressed with SUMO1. SUMO1P3 expression was significantly increased in patients with LUAD but not LUSC with reduced RFS after primary or follow-up treatment. Although patients with LUAD who had high SUMO1 or SUMO1P3 expression had reduced RFS compared with low expression groups, univariate and multivariate analysis showed that only SUMO1P3 expression was independently associated reduced RFS (HR, 1.418; 95% CI, 1.041-1.930; p=0.027). CONCLUSIONS SUMO1P3 expression was an independent indicator of reduced RFS in patients with LUAD.


Assuntos
Adenocarcinoma de Pulmão/genética , Neoplasias Pulmonares/genética , Pseudogenes , Proteína SUMO-1/genética , Adenocarcinoma de Pulmão/patologia , Idoso , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Progressão da Doença , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/patologia , Masculino , Análise Multivariada , Recidiva Local de Neoplasia/patologia , Proteína SUMO-1/metabolismo , Resultado do Tratamento , Regulação para Cima/genética
9.
Proc Natl Acad Sci U S A ; 113(8): 2023-8, 2016 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-26858435

RESUMO

Real-time online detection of trace threat analytes is critical for global sustainability, whereas the key challenge is how to efficiently convert and amplify analyte signals into simple readouts. Here we report an ultrasensitive microfluidic platform incorporated with smart microgel for real-time online detection of trace threat analytes. The microgel can swell responding to specific stimulus in flowing solution, resulting in efficient conversion of the stimulus signal into significantly amplified signal of flow-rate change; thus highly sensitive, fast, and selective detection can be achieved. We demonstrate this by incorporating ion-recognizable microgel for detecting trace Pb(2+), and connecting our platform with pipelines of tap water and wastewater for real-time online Pb(2+) detection to achieve timely pollution warning and terminating. This work provides a generalizable platform for incorporating myriad stimuli-responsive microgels to achieve ever-better performance for real-time online detection of various trace threat molecules, and may expand the scope of applications of detection techniques.


Assuntos
Dispositivos Lab-On-A-Chip , Chumbo/análise , Técnicas Analíticas Microfluídicas , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos , Sensibilidade e Especificidade
10.
Ann Hum Biol ; 46(3): 272-278, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31208213

RESUMO

Aim: Genetic polymorphisms and the mutation ratio of 19 autosomal short tandem repeat (STR) loci were analysed in 10,000 individuals and 7755 families from Jiangsu Province in Eastern China.Subjects and methods: Nineteen STR loci were amplified by a multiplex amplification system and genotyped on the ABI 3130 Genetic Analyser. Allele frequencies, forensic parameters and mutations for the 19 autosomal STR loci were statistically analysed.Results: In total, 344 genotypes were discovered. No significant deviation from Hardy-Weinberg equilibrium was observed. The combined power of discrimination reached 0.9999999999999999984341, and the combined probability of paternity exclusion was 0.999999989. The pairwise genetic distance and p-values between the Jiangsu and 17 published populations depended on the FST value calculation and are shown by the neighbour-joining evolutionary tree. No statistically significant differences were found, except for the Xinjiang Altay Han (p = 0.01802) population. The average mutation rate of the Jiangsu population across all 19 loci was 1.4 × 10-3. The average mutation rate of the 13 core CODIS STR loci remained below 2 × 10-3 and there was no difference and relatively high consistency (p < 0.001) by correlation coefficient analysis among the six groups.Conclusions: Allelic genetic polymorphisms and mutation data were obtained from a large number of samples, which indicated that the amplification kit is suitable for forensic application and that the Jiangsu population has its own genetic characteristics that are different from those of other ethnic populations.


Assuntos
Repetições de Microssatélites/genética , Taxa de Mutação , Polimorfismo Genético , Adulto , China , Etnicidade/genética , Humanos , Pessoa de Meia-Idade , Adulto Jovem
11.
Small ; 14(18): e1703650, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29611289

RESUMO

A novel thermoresponsive catalytic polyethersulfone membrane with multiscale pores is developed by constructing silver nanoparticles (Ag NPs) loaded poly(N-isopropylacrylamide) (PNIPAM) nanogels on pore walls of cellular pores as thermoresponsive gates and catalysts via vapor-induced phase separation. The Ag NPs are stably immobilized on the PNIPAM nanogels by an in situ reduction method based on the versatile adhesion and reduction properties of polydopamine. The micrometer cellular pores decorated with Ag NPs loaded PNIPAM nanogels are formed throughout the membrane and act as numerous microreactors with a large pore surface. The proposed membrane exhibits both satisfactory thermoresponsive characteristics and stable catalytic properties. The effects of operation temperature and reactant concentration of feed solution on the catalytic properties are investigated systematically. The results show that the apparent kinetic rate constant of catalytic reduction of 4-nitrophenol (4-NP) in water by reductant sodium borohydride (NaBH4 ), is ranging from 3.7 to 37.9 min-1 at temperatures from 20 to 45 ºC and the molar ratio of NaBH4 to 4-NP from 100:1 to 500:1. When the reactant concentration in feed solution fluctuates, the permeability or throughput of the membrane is simply adjusted by virtue of the thermoresponsive characteristics of membranes to achieve high catalytic conversion of reactant.

12.
Chemphyschem ; 19(16): 2025-2036, 2018 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-29539212

RESUMO

A simple device, which is equipped with a non-woven fabric filter medium immobilized with ion-recognizable smart hollow microgels, is developed for facile detection of trace lead(II) ions (Pb2+ ). The ion-recognizable smart microgels are made of poly(N-isopropylacrylamide-co-benzo-18-crown-6-acrylamide) (PNB), in which the 18-crown-6 groups act as the sensors of Pb2+ and the N-isopropylacrylamide groups act as the actuators. The PNB hollow microgels can isothermally change from a shrunk state to a swollen state in response to recognizing Pb2+ in the aqueous environment due to the electrostatic repulsion among the charged 18-crown-6/Pb2+ complex groups and the enhancement of hydrophilicity of the microgels. Due to the hollow structures, the PNB microgels show remarkable isothermal swelling ratio. Thus, the flux of solution pass through the non-woven fabric filter medium decreases significantly because of the remarkable reduction in the space for liquid flowing upon recognizing Pb2+ . The Pb2+ concentration can be detected quantitatively by simply and easily measuring the change of solution flux using the proposed device, which is operated without external power supply or spectroscopic measurements. The strategy proposed in this study provides a promising method for facile detection of trace Pb2+ in aqueous environments.

13.
Appl Microbiol Biotechnol ; 102(20): 8921-8930, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30120520

RESUMO

The effect of sodium chloride (NaCl) on pullulan production by batch culture of Aureobasidium pullulans CCTCC M 2012259 was investigated. NaCl at 3 g/L improved the pullulan titer by 26.7% but reduced the molecular weight of pullulan to only 46.8% of that obtained in the control without NaCl. In order to elucidate the physiological mechanism underlying the effect of NaCl on pullulan production, assays of key enzyme activity, gene expression, energy metabolism, and intracellular uridine diphosphate glucose (UDP-glucose) content were performed. Results indicated that NaCl increased the activities of α-phosphoglucose mutase and glucosyltransferase involved in pullulan biosynthesis, increased the activities of α-amylase being responsible for pullulan degradation, upregulated the transcriptional levels of pgm1, fks, and amy2 genes, enhanced the driving force for ATP supply, and helped to maintain intracellular UDP-glucose at a high level in A. pullulans CCTCC M 2012259. All these results illuminate the reason by which NaCl increases pullulan titer but reduces the molecular weight of pullulan.


Assuntos
Ascomicetos/metabolismo , Glucanos/metabolismo , Cloreto de Sódio/metabolismo , Ascomicetos/química , Ascomicetos/genética , Técnicas de Cultura Celular por Lotes , Fermentação , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Glucanos/química , Peso Molecular , alfa-Amilases/genética , alfa-Amilases/metabolismo
14.
Macromol Rapid Commun ; 38(23)2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28863248

RESUMO

This work reports on a facile and flexible strategy based on the deformation of encapsulated droplets in fiber-like polymeric matrices for template synthesis of controllable microstructured materials from nonspherical microparticles to complex 3D helices. Monodisperse droplets generated from microfluidics are encapsulated into crosslinked polymeric networks via an interfacial crosslinking reaction in microchannel to in situ produce the droplet-containing, fiber-like matrices. By stretching and twining the dried fiber-like matrices, the encapsulated droplets can be flexibly engineered into versatile shapes for template synthesis of controllable nonspherical microparticles and helices. Moreover, magnetic helices can be fabricated by simply dispersing magnetic Fe3 O4 nanoparticles in the droplets to achieve rotational and translational motion under a rotated magnetic field. This work provides a simple and versatile strategy for the template synthesis of advanced functional microstructured materials with flexible shapes.


Assuntos
Microfluídica/métodos , Polímeros/química , Nanopartículas de Magnetita/química , Técnicas Analíticas Microfluídicas , Tamanho da Partícula
15.
Chem Soc Rev ; 45(3): 460-75, 2016 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-26595416

RESUMO

Membranes are playing paramount roles in the sustainable development of myriad fields such as energy, environmental and resource management, and human health. However, the unalterable pore size and surface properties of traditional porous membranes restrict their efficient applications. The performances of traditional membranes will be weakened upon unavoidable membrane fouling, and they cannot be applied to cases where self-regulated permeability and selectivity are required. Inspired by natural cell membranes with stimuli-responsive channels, artificial stimuli-responsive smart gating membranes are developed by chemically/physically incorporating stimuli-responsive materials as functional gates into traditional porous membranes, to provide advanced functions and enhanced performances for breaking the bottlenecks of traditional membrane technologies. Smart gating membranes, integrating the advantages of traditional porous membrane substrates and smart functional gates, can self-regulate their permeability and selectivity via the flexible adjustment of pore sizes and surface properties based on the "open/close" switch of the smart gates in response to environmental stimuli. This tutorial review summarizes the recent developments in stimuli-responsive smart gating membranes, including the design strategies and the fabrication strategies that are based on the introduction of the stimuli-responsive gates after or during membrane formation, and the positively and negatively responsive gating models of versatile stimuli-responsive smart gating membranes, as well as the advanced applications of smart gating membranes for regulating substance concentration in reactors, controlling the release rate of drugs, separating active molecules based on size or affinity, and the self-cleaning of membrane surfaces. With self-regulated membrane performances, smart gating membranes show great power for use in global sustainable development.

16.
Proc Natl Acad Sci U S A ; 110(21): 8375-80, 2013 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-23671096

RESUMO

Synthetic nitrogen (N) fertilizer has played a key role in enhancing food production and keeping half of the world's population adequately fed. However, decades of N fertilizer overuse in many parts of the world have contributed to soil, water, and air pollution; reducing excessive N losses and emissions is a central environmental challenge in the 21st century. China's participation is essential to global efforts in reducing N-related greenhouse gas (GHG) emissions because China is the largest producer and consumer of fertilizer N. To evaluate the impact of China's use of N fertilizer, we quantify the carbon footprint of China's N fertilizer production and consumption chain using life cycle analysis. For every ton of N fertilizer manufactured and used, 13.5 tons of CO2-equivalent (eq) (t CO2-eq) is emitted, compared with 9.7 t CO2-eq in Europe. Emissions in China tripled from 1980 [131 terrogram (Tg) of CO2-eq (Tg CO2-eq)] to 2010 (452 Tg CO2-eq). N fertilizer-related emissions constitute about 7% of GHG emissions from the entire Chinese economy and exceed soil carbon gain resulting from N fertilizer use by several-fold. We identified potential emission reductions by comparing prevailing technologies and management practices in China with more advanced options worldwide. Mitigation opportunities include improving methane recovery during coal mining, enhancing energy efficiency in fertilizer manufacture, and minimizing N overuse in field-level crop production. We find that use of advanced technologies could cut N fertilizer-related emissions by 20-63%, amounting to 102-357 Tg CO2-eq annually. Such reduction would decrease China's total GHG emissions by 2-6%, which is significant on a global scale.


Assuntos
Pegada de Carbono , Indústria Química/métodos , Indústria Química/tendências , Conservação dos Recursos Naturais/métodos , Fertilizantes , Efeito Estufa/prevenção & controle , Nitrogênio , Indústria Química/economia , Indústria Química/legislação & jurisprudência , China , Conservação dos Recursos Naturais/economia , Conservação dos Recursos Naturais/tendências
17.
Appl Microbiol Biotechnol ; 99(1): 211-20, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25277414

RESUMO

In this study, pullulan production was achieved by whole-cell bioconversion with Aureobasidium pullulans CCTCC M 2012259. Response surface methodology was applied to optimize the seed medium for incubating cells with high capability of pullulan bioconversion. Three medium components, namely, yeast extract, MgSO4·7H2O, and glucose were identified by Plackett-Berman design as significant factors affecting the cells' pullulan bioconversion capability. A three-level Box-Behnken design was then employed to determine the optimal levels of the three components. A mathematical model was developed to show the influence of each medium component and its effects on the cells' pullulan bioconversion capability. The model predicted a maximum pullulan bioconversion capability of 32.28 mg/g/h at the optimal yeast extract, MgSO4·7H2O, and glucose concentrations of 3.57, 0.18, and 63.97 g/l, respectively. The validation experiments showed that the cells' pullulan bioconversion capability was improved by 23.1% when the optimal medium was used, as compared with that obtained with the basic medium. Subsequently, the gene expression and activities of the key enzymes involved in pullulan biosynthesis were evaluated. When the optimal medium was employed, the transcriptional levels of pgm1 and fks were up-regulated by 2.5- and 1.2-fold, respectively, and the α-phosphoglucose mutase and glucosyltransferase activities were increased by 17 and 19%, respectively, when compared with those achieved using the basic medium. These results indicated that pullulan bioconversion using A. pullulans CCTCC M 2012259 as the whole-cell catalyst is an attractive approach for efficient pullulan production and can be applied for the production of other polysaccharides.


Assuntos
Ascomicetos/crescimento & desenvolvimento , Ascomicetos/metabolismo , Glucanos/metabolismo , Biotransformação , Meios de Cultura/química , Modelos Teóricos
18.
Zhonghua Nan Ke Xue ; 21(12): 1098-101, 2015 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-26817302

RESUMO

OBJECTIVE: To assess the efficacy and safety of Saw Palmetto Extract Capsules in the treatment of benign prostatic hyperplasia (BPH). METHODS: We conducted a multi-centered open clinical study on 165 BPH patients treated with Saw Palmetto Extract Capsules at a dose of 160 mg qd for 12 weeks. At the baseline and after 6 and 12 weeks of medication, we compared the International Prostate Symptom Scores (IPSS), prostate volume, postvoid residual urine volume, urinary flow rate, quality of life scores (QOL), and adverse events between the two groups of patients. RESULTS: Compared with the baseline, both IPSS and QOL were improved after 6 weeks of medication, and at 12 weeks, significant improvement was found in IPSS, QOL, urinary flow rate, and postvoid residual urine. Mild stomachache occurred in 1 case, which necessitated no treatment. CONCLUSION: Saw Palmetto Extract Capsules were safe and effective for the treatment of BPH.


Assuntos
Extratos Vegetais/uso terapêutico , Hiperplasia Prostática/tratamento farmacológico , Cápsulas , Humanos , Masculino , Extratos Vegetais/efeitos adversos , Qualidade de Vida , Serenoa
19.
Langmuir ; 30(5): 1455-64, 2014 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-24437526

RESUMO

A simple and efficient method is developed to fabricate monodisperse and fast-responsive poly(N-isopropylacrylamide) (PNIPAM) microgels with open-celled porous structure. First, numerous fine oil droplets are fabricated by homogeneous emulsification method and are then evenly dispersed inside monodisperse PNIPAM microgels as porogens via the combination of microfluidic emulsification and UV-initiated polymerization methods. Subsequently, the embedded fine oil droplets inside the PNIPAM microgels are squeezed out upon stimuli-induced rapid volume shrinkage of the microgels; as a result, a spongelike open-celled porous structure is formed inside the PNIPAM microgels. The open-celled porous structure provides numerous interconnected free channels for the water transferring convectively inward or outward during the volume phase transition process of PNIPAM microgels; therefore, the response rates of the PNIPAM microgels with open-celled porous structure are much faster than that of the normal ones in both thermo-responsive shrinking and swelling processes. Because of the fast-responsive characteristics, the microgels with open-celled porous structure will provide ever better performances in their myriad applications, such as microsensors, microactuators, microvalves, and so on.


Assuntos
Resinas Acrílicas/química , Emulsões , Géis , Microscopia Eletrônica de Varredura , Porosidade , Temperatura , Fatores de Tempo
20.
Macromol Rapid Commun ; 35(14): 1280-6, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24719381

RESUMO

Novel dual molecular- and ion-recognition responsive poly(N-isopropylacrylamide-co-benzo-12-crown-4-acrylamide) (PNB12 C4 ) linear copolymers with benzo-12-crown-4 (B12C4) as both guest and host units are prepared. The copolymers exhibit highly selective sensitivities toward γ-cyclodextrin (γ-CD) and Na(+) . The presence of γ-CD induces the lower critical solution temperature (LCST) of PNB12 C4 copolymer to shift to a higher value due to the formation of 1:1 γ-CD/B12C4 host-guest inclusion complexes, while Na(+) causes a negative shift in LCST due to the formation of 2:1 "sandwich" B12C4/Na(+) host-guest complexes. Regardless of the complexation order, when γ-CD and Na(+) coexist with PNB12 C4 , competitive complexation actions of B12C4 as both guest and host units toward γ-CD and Na(+) finally form equilibrium 2:2:1 γ-CD/B12C4/Na(+) composite complexes, and the final LCST values of PNB12 C4 copolymer reach almost the same level. The results provide valuable guidance for designing and applying PNB12 C4 -based smart materials in various applications.


Assuntos
Acrilamida/química , Acrilamidas/química , Éteres de Coroa/química , Polímeros/química , Íons/química , Transição de Fase , Polímeros/síntese química , Sódio/química , gama-Ciclodextrinas/química
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