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1.
IEEE Trans Vis Comput Graph ; 29(12): 5124-5136, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36194712

RESUMO

View synthesis methods using implicit continuous shape representations learned from a set of images, such as the Neural Radiance Field (NeRF) method, have gained increasing attention due to their high quality imagery and scalability to high resolution. However, the heavy computation required by its volumetric approach prevents NeRF from being useful in practice; minutes are taken to render a single image of a few megapixels. Now, an image of a scene can be rendered in a level-of-detail manner, so we posit that a complicated region of the scene should be represented by a large neural network while a small neural network is capable of encoding a simple region, enabling a balance between efficiency and quality. Recursive-NeRF is our embodiment of this idea, providing an efficient and adaptive rendering and training approach for NeRF. The core of Recursive-NeRF learns uncertainties for query coordinates, representing the quality of the predicted color and volumetric intensity at each level. Only query coordinates with high uncertainties are forwarded to the next level to a bigger neural network with a more powerful representational capability. The final rendered image is a composition of results from neural networks of all levels. Our evaluation on public datasets and a large-scale scene dataset we collected shows that Recursive-NeRF is more efficient than NeRF while providing state-of-the-art quality. The code will be available at https://github.com/Gword/Recursive-NeRF.

2.
J Phys Condens Matter ; 33(15)2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33498026

RESUMO

We report growth, electronic structure and superconductivity of ultrathin epitaxial CoSi2films on Si (111). At low coverages, preferred islands with 2, 5 and 6 monolayers height develop, which agrees well with the surface energy calculation. We observe clear quantum well states as a result of electronic confinement and their dispersion agrees well with density functional theory calculations, indicating weak correlation effect despite strong contributions from Co 3delectrons.Ex situtransport measurements show that superconductivity persists down to at least 10 monolayers, with reducedTcbut largely enhanced upper critical field. Our study opens up the opportunity to study the interplay between quantum confinement, interfacial symmetry breaking and superconductivity in an epitaxial silicide film, which is technologically relevant in microelectronics.

3.
IEEE Trans Vis Comput Graph ; 27(7): 3305-3317, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32011257

RESUMO

We present prominent structures in video, a representation of visually strong, spatially sparse and temporally stable structural units, for use in video analysis and editing. With a novel quality measurement of prominent structures in video, we develop a general framework for prominent structure computation, and an efficient hierarchical structure alignment algorithm between a pair of videos. The prominent structural unit map is proposed to encode both binary prominence guidance and numerical strength and geometry details for each video frame. Even though the detailed appearance of videos could be visually different, the proposed alignment algorithm can find matched prominent structure sub-volumes. Prominent structures in video support a wide range of video analysis and editing applications including graphic match-cut between successive videos, instant cut editing, finding transition portals from a video collection, structure-aware video re-ranking, visualizing human action differences, etc.

4.
Artigo em Inglês | MEDLINE | ID: mdl-33136528

RESUMO

A new tadalafil analogue was detected via high-performance liquid chromatography (HPLC)-diode array detection (DAD) during routine screening of health foods suspected of adulteration with erectile dysfunction drugs. The UV absorption spectrum of the unknown was almost identical to that of tadalafil. The analogue was purified by preparative HPLC and structural elucidation carried out by mass spectrometric and NMR spectroscopic experiments. The spectral data revealed that this tadalafil analogue bears a benzyl group instead of the methyl group. The isolated compound was identified as N-benzyl tadalafil. Considering the risk it poses to public health, this new PDE-5 analogues for ED should be included on the inspection list for illegal products.


Assuntos
Café/química , Suplementos Nutricionais/análise , Contaminação de Medicamentos , Contaminação de Alimentos/análise , Inibidores da Fosfodiesterase 5/isolamento & purificação , Tadalafila/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Humanos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Inibidores da Fosfodiesterase 5/química , Tadalafila/análogos & derivados , Tadalafila/química
5.
Huan Jing Ke Xue ; 39(4): 1502-1511, 2018 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-29964974

RESUMO

Based on a dilution sampling system and domestic burning tests, size-segregated particles emitted from burning of three kinds of honeycomb coals (in view of flaming and smoldering burning conditions) and four kinds of raw coals, were collected by cascade impactors (FA-3). The contents of V, Cr, Mn, Co, Ni, Cu, Zn, As, Cd, Sb, and Pb were analyzed to get their emission factors (EFs) in different particle size fractions. Results indicated that:① Zn and Pb dominated the emitted mass of heavy metals from chunk (53.16%-65.76%) and honeycomb (96.08% in 0.43 µm) during the flaming combustion condition. However, the emission of Ni was increased from 30.70% to 52.36% in the smoldering condition. Thus, combustion condition may affect the composition of heavy metals in particle matters. ② In the flaming condition, both chunk and honeycomb emission factors of heavy metals were concentrated under 1.1 µm, while the larger sized particles in the range of 5.8-10 µm were distributed. So, heavy metal components may shift to the larger size of the particles at lower combustion temperatures. ③ Fine particle matters(PM) was divided into three categories based on the size distribution of 11 kinds of heavy metal emission factors. The maximum emission values of As and V fell under the PM size category of 5.8-10 µm. The fourth cycle transition metal elements, such as Cr, Mn, Cu, Ni, and Co, fell in the range of 1.1-2.1 µm and these elements represented similar emission characteristic features. Other elements, such as Pb, Sb, Cd, and Zn, were concentrated in sizes less than 0.43 µm. ④ The additive in the honeycomb during the process may import several kinds of heavy metals and may change the combustion temperature, which remodels the mechanism of heavy metal emission. Thus, honeycomb coal may emit different heavy metals under different combustion conditions.The heavy metal emission mechanism during honeycomb coal combustion needs further investigation and the emission reduction effects (especially of heavy metals) needs to be re-estimated.

6.
IEEE Trans Image Process ; 27(12): 5854-5865, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30047880

RESUMO

Selfie photography from the hand-held camera is becoming a popular media type. Although being convenient and flexible, it suffers from low camera motion stability, small field of view, and limited background content. These limitations can annoy users, especially, when touring a place of interest and taking selfie videos. In this paper, we present a novel method to create what we call a BiggerSelfie that deals with these shortcomings. Using a video of the environment that has partial content overlap with the selfie video, we stitch plausible frames selected from the environment video to the original selfie frames and stabilize the composed video content with a portrait-preserving constraint. Using the proposed method, one can easily obtain a stable selfie video with expanded background content by merely capturing some background shots. We show various results and several evaluations to demonstrate the applicability of our method.

7.
Huan Jing Ke Xue ; 39(8): 3524-3534, 2018 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-29998657

RESUMO

China is one of the most important contributors to the global burden of carbonaceous aerosols, of which domestic coal combustion occupies a large fraction. Uncertainty in the emission factors (EFs) directly influences the accuracy of corresponding emission inventories. In the present study, based on domestic burning tests with a dilution sampling system, nine size-segregated particle classes emitted from the burning of three kinds of honeycomb coals (under flaming and smoldering burning conditions) and four kinds of chunk coals, including bituminous and lignite, were collected via a cascade impactor (FA-3). Organic and elemental carbon (OC and EC, respectively) were analyzed using the thermal-optical method. The EFs of particulate matter (PM), OC, and EC for nine size ranges were obtained. For honeycomb coals, the EFs of OC and EC in PM2.1 were 0.07 g·kg-1 and 0.002 g·kg-1, respectively, under flaming burning conditions and 0.10 g·kg-1 and 0.001 g·kg-1, respectively, under smoldering burning conditions. Carbonaceous particles exhibited higher EFs under flaming burning conditions. For chunk coals, the EFs of OC and EC in PM2.1 were 1.4 g·kg-1 and 0.02 g·kg-1, respectively, which are about one magnitude higher than those for honeycomb coal burning. Particulate matter and its associated carbonaceous components preferred to concentrate in fine particles. The EFs of carbonaceous components peaked at the size of ≤ 0.43 µm and 0.43-0.65 µm for honeycomb coal burning and chunk coal burning, respectively.

8.
J Genet ; 97(1): 319-322, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29666351

RESUMO

The transcription factor forkhead box N1 (Foxn1) plays an important role in the development and function of thymic epithelial cells (TECs) in vertebrates. However, the transcriptional regulation of Foxn1 is still unknown. A series of dual luciferase report vectors were constructed and their relative activities were also detected. The 5'-untranslated regions contains two cis-acting elements, Sp1 and GATA-1, as well as trans-acting elements between positions -332 to -438. Nevertheless, the relative activities of Foxn1 promoter were significantly increased in PK15 cells only when the Sp1 was overexpressed, suggesting that the Sp1 was the most important sequence for Foxn1 transcription activation in the pig. Regrettably, the exact trans-acting elements were not found.


Assuntos
Fatores de Transcrição Forkhead/genética , Fator de Transcrição Sp1/metabolismo , Sus scrofa/genética , Animais , Linhagem Celular , Fatores de Transcrição Forkhead/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Luciferases/metabolismo , Mutação/genética , Regiões Promotoras Genéticas , Sus scrofa/metabolismo
9.
J Nanosci Nanotechnol ; 15(4): 2785-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26353493

RESUMO

The write and read performances of phase-change probe memory were investigated for the first time by a physics-based pure three dimensional model. The written crystalline bit possessed from this developed model demonstrates the potential of phase-change probe memory for ultra-high density, low energy consumption, high data rate, and good readability. The cross-talk effect on the write and read performances of phase-change probe memory, which can not be modelled by previous two dimensional models, is also evaluated. The findings showed that the bit and track pitches should be remained sufficiently long so as to eliminate the undesired interferences. The simulated results exhibited a good agreement with the experimental observations, thus demonstrating the physical reality of the designed model.

10.
Onco Targets Ther ; 8: 1245-50, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26060410

RESUMO

AIM: To retrospectively evaluate the safety and efficacy of ultrasound-guided percutaneous microwave ablation (MWA) combined with simultaneous transarterial chemoembolization (TACE) in the treatment of patients with advanced intrahepatic cholangiocarcinoma (ICC). METHODS: All patients treated with ultrasound-guided percutaneous MWA combined with simultaneous TACE for advanced ICC at our institution were included. Posttreatment contrast-enhanced computed tomography and/or magnetic resonance imaging were retrieved and reviewed for tumor response to the treatment. Routine laboratory studies, including hematology and liver function tests were collected and analyzed. Procedure-related complications were reviewed and survival rates were analyzed. RESULTS: From January 2011 to December 2014, a total of 26 advanced ICC patients were treated at our single institute with ultrasound-guided percutaneous MWA combined with simultaneous TACE. There were 15 males and eleven females with an average age of 57.9±10.4 years (range, 43-75 years). Of 26 patients, 20 (76.9%) patients were newly diagnosed advanced ICC without any treatment, and six (23.1%) were recurrent and treated with surgical resection of the original tumor. The complete ablation rate was 92.3% (36/39 lesions) for advanced ICC. There were no major complications observed. There was no death directly from the treatment. Median progression-free survival and overall survival were 6.2 and 19.5 months, respectively. The 6-, 12-, and 24-month survival rates were 88.5%, 69.2%, and 61.5%, respectively. CONCLUSION: The study suggests that ultrasound-guided percutaneous MWA combined with simultaneous TACE therapy can be performed safely in all patients with advanced ICC. The complete ablation rate was high and there was no major complication. The overall 24-month survival was 61.5%.

11.
Mol Med Rep ; 12(2): 3132-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25936729

RESUMO

Recombinant Streptococcus Protein G (PG) is a cell wall protein, which, when combined with mammal immunoglobulin, is used in separating antibody technology. High-density fermentation technologies using an engineered recombinant PG-producing bacteria as well as PG separation and purification technologies have a direct impact on the availability and application of PG. Through primary and secondary seed cultivation, a recombinant E. coli strain was subjected to high-density fermentation with controlled feed supplement concentration under stimulation with isopropyl ß-D-1-thiogalactopyranoside. The present study investigated the effect of factors including inoculum size, oxygen levels, pH and the cultivating method on the fermentation process, as well as the effect of the separation and purification technologies, including ultrasonication, nickel column affinity chromatography, Sephadex G-25 gel filtration chromatography and diethylaminoethanol-sepharose fast flow ion exchange chromatography on the yield and purity of PG. The efficiency of extraction was detected using SDS-PAGE. High-density fermentation yielded 80-150 g/l of bacteria and 1 g PG was obtained from one liter broth. The present study delivered a highly efficient novel method via which PG can be obtained at a high concentration and a purity >95%.


Assuntos
Proteínas de Bactérias/biossíntese , Escherichia coli/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Cromatografia de Afinidade , Cromatografia em Gel , Eletroforese em Gel de Poliacrilamida , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Fermentação , Expressão Gênica , Engenharia Genética , Concentração de Íons de Hidrogênio , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Sonicação , Tiogalactosídeos/farmacologia
12.
Onco Targets Ther ; 7: 1311-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25071374

RESUMO

The aims of this study were to assess the effect of transarterial chemoembolization (TACE) on circulating tumor cells (CTCs) in the peripheral blood and right atrium of patients with HCC and to evaluate whether perioperative shedding of CTCs affects time to progression of HCC. Before and after TACE, peripheral and right atrial blood samples (7.5 mL) were collected from 42 patients with HCC. CTCs were enriched using EpCAM antibody-conjugated magnetic beads. The number of CTCs was 0-30 and 0-54 in peripheral blood before and after TACE, respectively (P=0.166), and 0-65 and 0-98 in the right atrium before and after TACE, respectively (P=0.102). The number of CTCs was significantly different between the two samples both before (P=0.007) and after (P=0.021) TACE. There was no difference in time to progression between patients with and without an increase in the number of CTCs after TACE in either sample (P>0.05 for both). There were more CTCs in right atrial blood than in peripheral blood. The numbers of CTCs in both samples remained unchanged after TACE. Shedding of tumor cells did not affect time to progression of disease in patients with HCC.

13.
J Cancer Res Clin Oncol ; 140(7): 1125-36, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24756364

RESUMO

PURPOSE: Arsenic trioxide (ATO) has been found effective in several types of cancer cells, including acute promyelocytic leukemia, and recently in hepatocellular carcinoma (HCC). In this study, we investigated the role of ATO in regulating the invasive activity of HCC after transarterial embolization (TAE). METHODS: Cell migration and invasion were observed using Transwell and wound-healing assay. The molecular changes in E-cadherin, N-cadherin, and Vimentin of surviving tumor cells were determined by Western blotting. The effects of ATO on Twist activity of the tumor cells were further analyzed. In animal study, 40 male buffalo rats implanted with McA-RH7777 tumor in the liver were randomly divided into four groups: control, TAE, ATO, and TAE + ATO. TAE procedures were performed on the 14th day after implantation. Lung metastases were observed using fluorescence imaging, and the molecular changes in residual tumor cells were evaluated by Western blotting or immunohistochemistry. Tumor growth and survival analysis were also evaluated. RESULTS: Arsenic trioxide markedly reduced cell migration and invasiveness, which were enhanced by hypoxia after TAE. Western blot analysis revealed ATO inhibited the expression of epithelial-mesenchymal transition (EMT) markers by suppressing Twist. The marked suppression effect of ATO on invasiveness and metastatic potential related to EMT was also shown in tissue. CONCLUSION: The results of this study demonstrated that ATO is an effective anticancer agent in combination with TAE in the treatment of HCC, by suppressing tumor progression and metastasis via selectively inducing tumor cell apoptosis and arresting EMT by inhibiting the Twist activation.


Assuntos
Antineoplásicos/uso terapêutico , Arsenicais/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Embolização Terapêutica/efeitos adversos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Pulmonares/prevenção & controle , Óxidos/uso terapêutico , Proteína 1 Relacionada a Twist/antagonistas & inibidores , Animais , Trióxido de Arsênio , Carcinoma Hepatocelular/secundário , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Neoplasias Hepáticas/patologia , Neoplasias Pulmonares/secundário , Masculino , Metástase Neoplásica , Ratos , Ratos Endogâmicos BUF
15.
J Chem Phys ; 126(15): 154708, 2007 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-17461660

RESUMO

Electronic and magnetic properties of BiCoO(3) have been investigated using the ab initio density-functional calculations with local spin density approximation (LSDA) and LSDA+U methods. The structural stability and the origin of the multiferroism for ferroelectronic and ferromagnetic existence were addressed. It was shown that the stability of the C-type antiferromagnetic (C-AFM) structure is better than that of other possible configurations. The hybridization between Bi-O and Co-O with interplay and a local magnetic moment on the Co(3+) play important roles for the nature of the ferroelectricity and ferromagnetism. Theoretical calculations predict the insulating ground state with a band gap of 2.11 eV in the C-AFM ordering for BiCoO(3) originated from the antiferromagnetic interaction in the ab plane, which is in well agreement with experiments.

16.
J Chem Phys ; 124(17): 174701, 2006 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-16689584

RESUMO

First-principles calculations are employed to study the surface relaxation and electronic structure of the fully relaxed SrTiO(3) (001) oxygen-vacancy surfaces with both Sr and Ti terminations. In contrast to the perfect surface, the larger surface rumples and smaller interlayer distances have been found. Some in-gap Ti 3d states at about -1.13 eV below the Fermi level were observed in the Ti-terminated surface caused by oxygen vacancies. For the Sr-terminated oxygen-vacancy surface, some in-gap Ti 3d states move into the bulk midgap region to become partially occupied. These theoretical results are in agreement with the experimental data.

17.
Yi Chuan ; 28(1): 36-8, 2006 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-16469714

RESUMO

ESR (Estrogen Receptor) gene has been determined to be one of the major genes affecting phenotype of litter size without any genetic negative correlation to growth and carcass trait. Recent studies mainly focused on the PvuII enzyme site found by Rothschild in 1996. An optimized standard PCR-SSCP protocol was employed to detect the exon 7 of ESR gene. The results showed that there were a new mutation site and three genotypes, which may be used as a new DNA marker site to further research.


Assuntos
Polimorfismo Genético/genética , Receptores de Estrogênio/genética , Animais , Éxons/genética , Genótipo , Mutação , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples/genética , Suínos
18.
J Phys Chem B ; 109(20): 9966-9, 2005 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-16852204

RESUMO

The universal models of nucleation thermodynamics and growth kinetics were established for nanowire growth upon metal-catalyst-assisted thermal chemical vapor transport on the basis of vapor-liquid-solid (VLS) mechanism. The thermodynamic and kinetic size limit of nanowire growth was deduced from the proposed model. Theoretical predictions are in agreement with experimental data.

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