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1.
Opt Express ; 28(9): 13895-13906, 2020 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-32403855

RESUMO

Compact high-power yellow laser is a critical part for sodium beacon adaptive optical systems. A narrow-linewidth quasi-continuous-wave (QCW) solid-state 589 nm laser with high-power and high beam quality simultaneously is investigated here, operating in hundreds-microsecond pulse duration with a tunable repetition rate of 400 to 1 kHz, which is flexible to allow the telescope to move in observing direction. The laser source is based on employing sum-frequency generation between 1319 and 1064 nm QCW Nd:YAG amplifiers. For a 100 µs pulse duration and 400 Hz repetition rate, the yellow laser provides a highest output power of 86.1 W with beam quality M2 = 1.37. The central wavelength can be precisely tuned to sodium-D2a line at 589.159 nm with a ∼440 MHz linewidth. This is the maximum power-reported for all-solid-state sodium guide star laser demonstrated to date. The result represents a key step toward solving the requirement of multi-conjugate adaptive optics for large adaptive optical telescopes.

2.
Opt Lett ; 45(7): 1818-1821, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32236007

RESUMO

A 100 W level kilohertz repetition-rate microsecond (µs)-pulse all-solid-state sodium beacon laser at 589 nm is demonstrated for the first time, to the best of our knowledge, via combining two independent µs-pulsed lasers. Each beamlet is generated by the sum-frequency mixing of pulsed 1064 and 1319 nm lasers in a lithium triborate (LBO) crystal, which operate at 500 Hz pulse repetition frequency with 61 W $p$p-polarized and 53 W $s$s-polarized output, respectively. An incoherent sequence combining technology of polarized laser beams is employed to add the two beamlets. The average power of the combined beam is up to 107.5 W with a combining efficiency of 94.3%. The combined beam has a 1 kHz repetition rate with ${\sim}{120}\;\unicode{x00B5} {\rm s}$∼120µs pulse duration and beam quality ${M^2} = {1.41}$M2=1.41. The central wavelength with a linewidth of ${\sim}{0.3}\;{\rm GHz}$∼0.3GHz is locked to a sodium ${{\rm D}_{2a}}$D2a absorption line. To the best of our knowledge, this is a record-high power operating at kilohertz for µs-pulsed solid-state sodium beacon lasers.

3.
Int J Biol Macromol ; 150: 1084-1092, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31759003

RESUMO

A water-soluble heteropolysaccharide was isolated and purified from Enteromorpha prolifera by DEAE-52 and Bio-Gel P-2 column chromatography. Fourier transform infrared spectroscopy (FTIR), high performance liquid chromatography (HPLC), multi-angle laser light scattering (MALLS), and nuclear magnetic resonance (NMR) spectroscopy were used to characterize the structure of E. prolifera polysaccharide degradation (EPP-1). Its anti-oxidative activity was determined in Caenorhabditis elegans via modulation of microRNAs. The average molecular weight of EPP-1 was 4.28 kDa. It contained six types of linkage units as →2)-ß-d-GlcpA-(1→, →3,6)-ß-d-Manp-(1→, →4)-α-d-Glcp-(1→, →6)-ß-d-Galp-(1→, ß-l-Rhap-(1→, and →4)-ß-d-GalpA-(1→. The mean lifespan, ultraviolet-induced oxidative stress, and thermotolerance in C. elegans were improved after treatment of EPP-1. Moreover, EPP-1 significantly increased the total superoxide dismutase levels and decreased the malondialdehyde levels in C. elegans. Intracellular reactive oxygen species accumulation and DNA damage were ameliorated by up-regulation of SKN-1 and DAF-16 expression through miR-48 and miR-51 miR-186 down-regulation. In vivo studies demonstrated that EPP-1 might be applied in functional foods as the antioxidative and anti-ageing ingredient.

4.
J Sci Food Agric ; 100(2): 672-681, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31583701

RESUMO

BACKGROUND: Hibiscus sabdariffa is commonly used in daily life and its extract is applied widely in food and cosmetics. However, it has not been evaluated for its anti-aging effects. RESULTS: Hibiscus sabdariffa calyx aqueous extract (HSCAE) has shown potential collagenase activity suppression effects, together with tyrosinase activity inhibition, and anti-oxidation as a free radical scavenger. The current investigation demonstrated that HSCAE was not cytotoxic in skin fibroblasts, and it significantly decreased ultraviolet B (UVB)-induced reactive oxygen species (ROS) on a flow cytometry assay. Moreover, HSCAE reduced matrix metalloproteinase (MMP) expression, increased tissue inhibition of metalloproteinase (TIMP)-1 level, and enhanced collagen content by inhibiting collagenase activity. It also blocked mRNA and protein expressions of melanin production pathway key factors, including the microphthalmia-associated transcription factor (MITF), tyrosinase, tyrosinase-related protein-1 (TRP-1), and dopachrome tautomerase-2 (TRP-2). CONCLUSION: These results demonstrated, for the first time, the potential of HSCAE as a natural antioxidant with the ability to maintain collagen production and to decrease melanin syntheses under UVB radiation, for anti-aging effects. © 2019 Society of Chemical Industry.


Assuntos
Depuradores de Radicais Livres/farmacologia , Hibiscus/química , Extratos Vegetais/farmacologia , Envelhecimento da Pele/efeitos dos fármacos , Animais , Linhagem Celular , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/efeitos da radiação , Humanos , Oxirredutases Intramoleculares/genética , Oxirredutases Intramoleculares/metabolismo , Camundongos , Monofenol Mono-Oxigenase/genética , Monofenol Mono-Oxigenase/metabolismo , Oxirredutases/genética , Oxirredutases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Envelhecimento da Pele/efeitos da radiação , Raios Ultravioleta/efeitos adversos
5.
Medicine (Baltimore) ; 98(49): e18252, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31804356

RESUMO

INTRODUCTION: Lumbar spondylodiscitis is a rare and severe complication of laparoscopic sacrohysteropexy with a polypropylene mesh. However, a case of lumbar spondylodiscitis following laparoscopic sacrohysteropexy has not been reported so far. We present a case of lumbar spondylodiscitis following laparoscopic sacrohysteropexy with a mesh. We also discuss 33 cases of lumbar spondylodiscitis following sacral colpopexy and (or) rectopexy with a mesh. PATIENT CONCERNS: A 46-year-old woman with 3 previous vaginal deliveries underwent laparoscopic mesh sacrohysteropexy for stage III uterine prolapse. One month after surgery, the patient developed persistent symptoms, such as stiffness of the lumbosacral portion, low back pain (LBP), persistent swelling, pain between the right iliac crest and the buttock, inability to bend down, and pain in the right lower limb. Symptoms were alleviated by a nonsteroidal anti-inflammatory drug. However, in the last 7 days, symptoms worsened and she was unable to stand or walk. The patient had very limited leg mobility. DIAGNOSIS: Blood routine examination, erythrocyte sedimentation rate, C-reactive protein, and magnetic resonance imaging (MRI) of the lumbar spine indicated lumbar pyogenic spondylodiscitis. INTERVENTIONS: Removal of mesh and hysterectomy via laparoscopy were performed immediately, and antibiotics were given simultaneously. However, on the basis of MRI findings and persistent symptoms, debridement, laminectomy, spinal canal decompression, bone grafting, and internal fixation via pedicle screw placement were performed 5 months after laparoscopic sacrohysteropexy. OUTCOMES: All symptoms were alleviated 5 days after the operation. The patient could stand in the erect position and raise her lower limbs within 2 weeks. She could resume her normal activities within 2 months after the operation, and her X-ray appeared normal. CONCLUSION: Persistent LBP and radiating pain may be the signals of lumbar spondylodiscitis. MRI is the gold standard diagnostic examination for lumbar spondylodiscitis. Awareness of symptoms, such as LBP and radiating pain symptoms, timely diagnosis, mesh removal, and referral to orthopedists are important to prevent more severe complications. Surgical practice needs to be improved further and any other infections should be treated immediately as the most likely causes of lumbar spondylodiscitis are related to the mesh and other infections.


Assuntos
Discite/etiologia , Discite/cirurgia , Vértebras Lombares , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Telas Cirúrgicas/efeitos adversos , Prolapso Uterino/cirurgia , Parafusos Ósseos , Transplante Ósseo , Desbridamento , Descompressão Cirúrgica , Diagnóstico Diferencial , Discite/diagnóstico , Feminino , Humanos , Laminectomia , Imagem por Ressonância Magnética , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico
6.
Medicine (Baltimore) ; 98(39): e17295, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31574851

RESUMO

BACKGROUND: In this study, investigators will evaluate the efficacy and safety of lactulose for the treatment of irritable bowel syndrome (IBS). METHODS: Literature search for relevant studies up to present will be conducted in MEDICINE, EMBASE, Google Scholar, Web of Science, Cochrane Library, Wangfang, Allied and Complementary Medicine Database, Chinese Biomedical Literature Database, and China National Knowledge Infrastructure. The included studies are randomized controlled trials of lactulose in patients with IBS. We will use RevMan 5.3 software using statistical analysis. RESULTS: This study will provide a high-quality integration of current evidence of lactulose for treating IBS on several aspects including global IBS symptoms, abdominal pain, defecation urgency, stool frequency, stool consistency, quality of life, and adverse events. CONCLUSIONS: This study will provide the evidence for the clinical efficacy and safety of lactulose for the treatment of IBS. PROSPERO REGISTRATION NUMBER: PROSPERO CRD42019140639.


Assuntos
Fármacos Gastrointestinais/uso terapêutico , Síndrome do Intestino Irritável/tratamento farmacológico , Lactulose/uso terapêutico , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Projetos de Pesquisa , Revisões Sistemáticas como Assunto , Resultado do Tratamento
7.
BMC Infect Dis ; 19(1): 762, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31477028

RESUMO

BACKGROUND: Avian influenza A (H5N6) virus poses a great threat to the human health since it is capable to cross the species barrier and infect humans. Although human infections are believed to largely originate from poultry contaminations, the transmissibility is unclear and only limited information was available on poultry environment contaminations, especially in Fujian Province. METHODS: A total of 4901 environmental samples were collected and tested for Avian Influenza Virus (AIV) from six cities in Fujian Province through the Fujian Influenza Surveillance System from 2013 to 2017. Two patient-related samples were taken from Fujian's first confirmed H5N6 human case and his backyard chicken feces in 2017. Chi-square test or Fisher's exact probability test was used to compare the AIV and the viral subtype positive rates among samples from different Surveillance cities, surveillance sites, sample types, and seasons. Phylogenetic tree analysis and molecular analysis were conducted to track the viral transmission route of the human infection and to map out the evolutions of H5N6 in Fujian. RESULTS: The overall positive rate of the H5 subtype AIVs was 4.24% (208/4903). There were distinctive differences (p < 0.05) in the positive rates in samples from different cities, sample sites, sample types and seasons. The viruses from the patient and his backyard chicken feces shared high homologies (99.9-100%) in all the eight gene segments. Phylogenetic trees also showed that these two H5N6 viruses were closely related to each other, and were classified into the same genetic clade 2.3.4.4 with another six H5N6 isolates from the environmental samples. The patient's H5N6 virus carried genes from H6N6, H5N8 and H5N6 viruses originated from different areas. The R294K or N294S substitution was not detected in the neuraminidase (NA). The S31 N substitution in the matrix2 (M2) gene was detected but only in one strain from the environmental samples. CONCLUSIONS: The H5 subtype of AIVs has started circulating in the poultry environments in Fujian Province. The patient's viral strain originated from the chicken feces in his backyard. Genetic reassortment in H5N6 viruses in Fujian Province was indicated. The H5N6 viruses currently circulating in Fujian Province were still commonly sensitive to Oseltamivir and Zanamivir, but the resistance against Amantadine has emerged.


Assuntos
Vírus da Influenza A/isolamento & purificação , Influenza Aviária/virologia , Influenza Humana/epidemiologia , Influenza Humana/virologia , Infecções por Orthomyxoviridae/virologia , Aves Domésticas/virologia , Animais , Embrião de Galinha , Galinhas/virologia , China/epidemiologia , Patos/virologia , Meio Ambiente , Microbiologia Ambiental , Genes Virais , Abrigo para Animais/normas , Humanos , Vírus da Influenza A/genética , Influenza Aviária/diagnóstico , Influenza Aviária/epidemiologia , Tipagem Molecular , Infecções por Orthomyxoviridae/diagnóstico , Infecções por Orthomyxoviridae/epidemiologia , Infecções por Orthomyxoviridae/transmissão , Filogenia , Doenças das Aves Domésticas/diagnóstico , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/virologia , Fatores de Risco
8.
Nat Commun ; 10(1): 3794, 2019 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-31439832

RESUMO

One of the central problems in quantum theory is to characterize, detect, and quantify quantumness in terms of classical strategies. Dephasing processes, caused by non-dissipative information exchange between quantum systems and environments, provides a natural platform for this purpose, as they control the quantum-to-classical transition. Recently, it has been shown that dephasing dynamics itself can exhibit (non)classical traits, depending on the nature of the system-environment correlations and the related (im)possibility to simulate these dynamics with Hamiltonian ensembles-the classical strategy. Here we establish the framework of detecting and quantifying the nonclassicality for pure dephasing dynamics. The uniqueness of the canonical representation of Hamiltonian ensembles is shown, and a constructive method to determine the latter is presented. We illustrate our method for qubit, qutrit, and qubit-pair pure dephasing and describe how to implement our approach with quantum process tomography experiments. Our work is readily applicable to present-day quantum experiments.

9.
Food Chem Toxicol ; 128: 233-239, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30995513

RESUMO

The contributions to hypoglycemic function and gut microbiota regulation by water and ethanol extracts of the microalgae Chlorella pyrenoidosa and Spirulina platensis were determined. An ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry analysis indicated that most of the compounds in the 55% ethanol extracts of C. pyrenoidosa (CP55) and S. platensis (SP55) were polyunsaturated fatty acids. After an 8-week high-fat high-sucrose diet with C. pyrenoidosa and S. platensis supplementation, glucose tolerance was improved, and the composition of the gut microbiota was altered. The diversity of the gut bacterial community was evaluated using 16S rRNA gene pyrosequencing. C. pyrenoidosa supplementation increased the abundance of Ruminococcus, Parasutterella, and Erysipelotrichacea and decreased the abundance of Lactobacillus, Turicibacter, and Blautia; S. platensis supplementation increased the abundance of Oscillibacter, Parasutterella, and Alloprevotella and decreased the abundance of Turicibacter. Moreover, Erysipelotrichacea and Ruminococcus were uniquely increased in C. pyrenoidosa treatment groups. Thus, CP55 and SP55 may be developed as effective natural food materials for preventing diabetes, and Ruminococcus may play a vital role in the treatment of diabetes.


Assuntos
Chlorella/química , Ácidos Graxos Insaturados/análise , Hipoglicemiantes/farmacologia , Spirulina/química , Animais , Cromatografia Líquida de Alta Pressão/métodos , Microbioma Gastrointestinal/genética , Teste de Tolerância a Glucose , Masculino , Espectrometria de Massas/métodos , RNA Ribossômico 16S/genética , Ratos , Especificidade da Espécie
10.
Inorg Chem ; 57(22): 14116-14122, 2018 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-30376302

RESUMO

Water-soluble wheel-like icosanuclear peroxotitanate K16[Ti20(µ-O)8(HO2)8(O2)12( R, R-tart)12]·52H2O (1) chelated by tartrate has been successfully isolated. As the largest peroxotitanate reported, {Ti20} features 20 (hydro)peroxo groups with three kinds of coordination modes in µ-η1:η2, µ-η2:η2, and η2 fashions. The cluster is stable in solution and solid states. It has been tested for the catalytic oxidations of methyl phenyl sulfide and pyridine with hydrogen peroxide, respectively, which shows reversible elimination and the addition of peroxo groups. This provides a rare example of well-characterized titanium peroxide for homogeneous catalysis and mechanism research.

11.
Dalton Trans ; 47(22): 7412-7421, 2018 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-29786717

RESUMO

Glycolato and R,S-lactato imidazole molybdenum(iv) complexes [Mo3SO3(glyc)2(im)5]·im·H2O (1), Na2[Mo3SO3(R,S-lact)3(im)3]·10H2O (2), and [Mo6O10(R,S-lact)2(im)10]·16H2O (3) have been isolated and characterized (H2glyc = glycolic acid, H2lact = lactic acid, im = imidazole). α-Alkoxy coordination with molybdenum [Mo-Oα-alkoxy 1.993(7)av Å] in 1 and 2 showed obvious differences to their counterpart with α-hydroxy coordination [MoIV3S4(PPh3)3(Hlact)2(lact)] [2.204(4)av Å] as shown in M. N. Sokolov, S. A. Adonin, A. V. Virovets, P. A. Abramov, C. Vicent, R. Llusar and V. P. Fedin, Inorg. Chim. Acta, 2013, 395, 11-18. This was also true for the 36 reported structures of FeMo-cofactors in the RCSB protein data bank (Mo-Oav 2.272 Å), which can serve as indirect evidence for the protonation of homocitrate in FeMo-co. The C-OHα-hydroxy bonds were longer than the short C-Oα-alkoxy bonds. Trinuclear Mo3SO3 cores were stabilized by imidazoles and/or α-hydroxycarboxylates, whereas only two glycolates were present in 1. α-Hydroxycarboxylates in 1 and 2 acted as bidentate ligands of Mo(iv) atoms through α-alkoxy and α-carboxy groups, while the imidazoles coordinated monodentately with nitrogen atoms. The lactates in 3 coordinated with Mo(iv) atoms through two oxygen atoms of α-carboxy groups, leaving the α-hydroxy group free. Furthermore, novel hexanuclear oxomolybdenum(v) malate Na6[(Mo2O4)3(mal)4]·5H2O (4) was also isolated (H3mal = malic acid). Solid-state and solution 13C NMR resonances of carbon atoms in α-alkoxy groups appeared in a high-field region (71.6, 77.4 ppm), indicating that α-alkoxy groups were easy to protonate.


Assuntos
Carbonatos/química , Imidazóis/química , Molibdênio/química , Molibdoferredoxina/química , Nitrogenase/química , Glicolatos/química , Ferro/metabolismo , Ácido Láctico/química , Ligantes , Malatos/química , Nitrogênio/metabolismo , Conformação Proteica , Prótons , Ácidos Tricarboxílicos/química
13.
Phys Rev Lett ; 120(3): 030403, 2018 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-29400538

RESUMO

The incoherent dynamical properties of open quantum systems are generically attributed to an ongoing correlation between the system and its environment. Here, we propose a novel way to assess the nature of these system-environment correlations by examining the system dynamics alone. Our approach is based on the possibility or impossibility to simulate open-system dynamics with Hamiltonian ensembles. As we show, such (im)possibility to simulate is closely linked to the system-environment correlations. We thus define the nonclassicality of open-system dynamics in terms of the nonexistence of a Hamiltonian-ensemble simulation. This classifies any nonunital open-system dynamics as nonclassical. We give examples for open-system dynamics that are unital and classical, as well as unital and nonclassical.

14.
Medicine (Baltimore) ; 96(43): e8322, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29069003

RESUMO

BACKGROUND AND STUDY AIMS: The approach to small bowel preparation before capsule endoscopy (CE) is still suboptimal. PATIENTS AND METHODS: One hundred eighty patients were randomly allocated to 3 groups. Patients in Group A took 250 mL 20% mannitol and 1 L 0.9% saline orally at 05:00 hours on the day of the procedure. In Group B the same preparation was taken at 20:00 on the day before, and at 05:00 on the day of CE; in addition, 20 mL oral simethicone was taken 30 minutes before CE. Group C was treated identically to Group B, except that the patients fasted for 3 days and took 3 g senna orally 3 times daily before CE. The length of bowel containing green luminal contents was assessed by ImageJ software and bowel cleanliness was evaluated by computed assessment of the cleansing score. RESULTS: Cleansing of the whole small bowel and the distal small bowel were significantly different between the 3 groups (χ = 22.470, P = .000; χ = 17.029, P = .000, respectively). There were also significant differences between the 3 groups in the length of small bowel and specifically the length of the distal small bowel containing green luminal contents (χ = 12.390, P = .000, χ = 15.141, P = .000, respectively), but not with regard to the proximal small bowel (χ = 0.678, P = .509). CONCLUSIONS: Three days fasting and oral senna, combined with 20% mannitol and simethicone, before CE, can reduce the effects of bile on the small bowel and improve small bowel cleansing, especially in the distal small intestine.


Assuntos
Endoscopia por Cápsula , Catárticos/administração & dosagem , Intestino Delgado , Manitol/administração & dosagem , Extrato de Senna/administração & dosagem , Simeticone/administração & dosagem , Administração Oral , Adulto , Idoso , Endoscopia por Cápsula/efeitos adversos , Endoscopia por Cápsula/métodos , Esquema de Medicação , Jejum , Feminino , Gastroenteropatias/diagnóstico , Humanos , Intestino Delgado/efeitos dos fármacos , Intestino Delgado/fisiopatologia , Masculino , Pessoa de Meia-Idade , Planejamento de Assistência ao Paciente , Resultado do Tratamento
15.
Org Biomol Chem ; 15(25): 5395-5401, 2017 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-28621782

RESUMO

Chiral amino alcohol-copper(ii) catalysts Cu-L1c and Cu-ent-L1c were utilized to promote the diastereoselective nitroaldol reactions of chiral aldehydes (S)-3 or (R)-3 with nitromethane, which respectively led to the preferential formation of certain stereoisomer for nitro diol derivatives 4. Using this catalytic protocol, all the four stereoisomers of the antidepressant reboxetine were divergently prepared. The highest overall yield of this synthetic route reached up to 30.5% from aldehyde (S)-3.


Assuntos
Antidepressivos/química , Antidepressivos/síntese química , Morfolinas/química , Morfolinas/síntese química , Estrutura Molecular , Reboxetina , Estereoisomerismo
16.
Org Biomol Chem ; 15(6): 1530-1536, 2017 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-28116376

RESUMO

Chiral ß-amino alcohol ligands were found effective for the copper(ii)-catalyzed asymmetric Henry reaction of benzofuran-2-carbaldehydes with nitromethane, which led to the formation of (S)-enriched benzofuryl ß-nitro alcohols with satisfactory enantioselectivities (up to 98% ee). Using this catalytic protocol, bioactive (S)-benzofuryl ß-amino alcohols could be conveniently prepared in short steps.

17.
Phys Rev E ; 94(5-1): 052101, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27967118

RESUMO

Photosynthesis has been a long-standing research interest due to its fundamental importance. Recently, studies on photosynthesis processes also have inspired attention from a thermodynamical aspect when considering photosynthetic apparatuses as biological quantum heat engines. Quantum coherence is shown to play a crucial role in enhancing the performance of these quantum heat engines. Based on the experimentally reported structure, we propose a quantum heat engine model with a non-Markovian vibrational mode. We show that one can obtain a performance enhancement easily for a wide range of parameters in the presence of the vibrational mode. Our results provide insights into the photosynthetic processes and a design principle mimicking natural organisms.


Assuntos
Modelos Biológicos , Fotossíntese , Temperatura Alta , Teoria Quântica , Vibração
18.
ACS Appl Mater Interfaces ; 8(33): 21603-11, 2016 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-27491888

RESUMO

Optical imaging-guidance of indocyanine green (ICG) for photothermal therapy (PTT) has great latent capacity in cancer therapy. However, the conventional optical image-guidance mode has caused strong tissue autofluorescence of the living tissue, which leads to the accurate infrared light irradiation cannot be conducted. In this article, ICG and persistent luminescence phosphors (PLPs) coloaded mesoporous silica nanocarriers ((ICG+PLPs)@mSiO2) were first designed and prepared for persistent luminescent imaging-guided PTT. The (ICG+PLPs)@mSiO2 nanocarriers could significantly improve signal-to-noise ratio during luminescence imaging-guided PTT, making the PLP promising for improving the accuracy of the tumor site for photothermal therapy in vivo. This paper is likely to develop a new way for accurately regulating cancer cell death based on luminescence imaging-guided PTT selectively triggered by near-infrared (NIR)-remote.


Assuntos
Luminescência , Verde de Indocianina , Nanoestruturas , Fototerapia , Dióxido de Silício
19.
Sci Total Environ ; 569-570: 1289-1298, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27436775

RESUMO

In order to improve our understanding of bio-activated carbon (BAC) filter, the water quality of influent and effluent treated with BAC in a drinking water treatment plant (DWTP) of Shanghai during 2015 was valued. Combining the results from UV254, SUVA254, dissolved organic carbon (DOC) and scanning electron microscopic (SEM), it is found that performance of BAC treatment will be affected by characteristics of activated carbon (AC), which is relevant to the type of activated carbon (including shape and operating time) in this study. Fluorescence excitation-emission matrix (FEEM) shows that the humification index (HIX) and index of recent autochthonous contribution (BIX) is a reliable indicator to descript the variation of dissolved organic matter (DOM) during BAC process. The pattern of variation in BIX and HIX implies that soluble microbial products (SMPs) are formed and humic-like substances are removed during BAC treatment, which is also confirmed by the change of peaks of FEEM in BAC effluent. Large, positive correlations between SUVA254 and disinfection by-products formation potential yield (DBPFP yield) demonstrate that UV-absorbing DOM is directly related to the generation of DBPs. Poor correlations of HIX with DBPFP suggest that non-humic substances with UV-absorbing properties play an important role in the generation of DBPs in water with low SUVA254. Finally, strong but negative correlations between BIX and DBPFP suggest that vigorous microbial metabolism of BAC results in a decrease in DBPFP. However, the DBPFP yield will be enhanced for the generation of SMPs by BAC, especially in summer.


Assuntos
Carvão Vegetal/química , Desinfetantes/análise , Água Potável/química , Poluentes Químicos da Água/análise , Purificação da Água , Qualidade da Água , China , Cidades , Fluorescência
20.
Opt Lett ; 41(8): 1732-5, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-27082331

RESUMO

A 65 W quasi-continuous-wave microsecond-pulse solid-state sodium beacon laser tuned to the sodium D2a line has been developed with a linewidth of 0.3 GHz, beam quality of M2=1.38, and pulse width of 120 µs at a repetition rate of 500 Hz by sum-frequency mixing 1319 and 1064 nm diode-pumped Nd:YAG master-oscillator power-amplifier systems. The laser wavelength stability is less than ±0.15 GHz through feedback controlling. The laser spiking due to relaxation oscillations is suppressed by inserting frequency doublers in both 1319 and 1064 nm oscillators. Sodium D2b re-pumping is accomplished by tuning the frequency of the electro-optic modulator with the right D2a-D2b offset. A bright sodium laser guide star with a photon return of 1820 photons/cm2/s was achieved with the laser system when a 32 W circular polarized beam was projected to the sky during our field test at the Xinglong Observatory.

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