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Optimal strategy for low surface brightness imaging with KMTNet

  • Byun, Woowon;Kim, Minjin;Sheen, Yun-Kyeong;Ho, Luis C.;Lee, Joon Hyeop;Jeong, Hyunjin;Kim, Sang Chul;Park, Byeong-Gon;Seon, Kwang-Il
    • The Bulletin of The Korean Astronomical Society
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    • v.43 no.1
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    • pp.42.4-43
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    • 2018
  • Most galaxies are believed to evolve through mergers and accretions. In particular, minor mergers and gas accretion appear to play an important role in galaxy evolution in the present-day Universe. Tidally-disrupted debris from such processes remain as diffuse, low-surface brightness structures because the dynamical timescale in the outskirts is significantly longer than that in the central regions. Although these structures will give us useful insight into the mass assembly history of galaxies, it is difficult to detect them due to their faint surface brightness. In order to investigate the structural properties of outskirts in nearby galaxies, we conduct deep and wide-field imaging survey with KMTNet. We present our observing strategy and an optimal data reduction process to recover faint extended features in the images of KMTNet. Using the imaging data of NGC 1291 obtained from KMTNet, we find that a peak-to-peak sky gradient can be reduced less than 0.4-0.6% of the original sky level in the entire image. We also find that we can reach the surface brightness of ${\mu}_{(B,1{\sigma})}$ ~ 29.5, ${\mu}_{(R,1{\sigma})}$ ~ 28.5 mag $arcsec^{-2}$ in one-dimensional profile, that is mainly limited by the uncertainty in the sky determination. It indicates that deep imaging data of KMTNet is suitable to study the extended faint features of nearby galaxies, such as stellar halos, outer disks, and dwarf companions.

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Carcass Characteristics and Chemical Composition of the Longissimus Muscle of Puruna and 1/2 Puruna vs. 1/2 Canchin Bulls Meat Quality of Bulls

  • Nunes do Prado, Ivanor;Rotta, Polyana Pizzi;Martin do Prado, Rodolpho;Visantainer, Jesui Vergilio;Moletta, Jose Luis;Perotto, Daniel
    • Asian-Australasian Journal of Animal Sciences
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    • v.21 no.9
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    • pp.1296-1302
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    • 2008
  • This work was conducted to study the performance, carcass characteristics, chemical composition and fatty acid profile of the Longissimus muscle (LM) of first-generation Purunã (n = 7, PUR1), second-generation Purunã (n = 9, PUR2), and 1/2 Puruna vs. 1/2 Canchin (n = 13, PUCA) bulls finished in a feedlot. The animals averaged 18 months of age at the beginning of the experiment. The animals were kept in a feedlot from 18 to 22 months of age. They were fed twice a day with corn silage ad libitum, along with soybean meal, cracked corn, urea, limestone and mineral salt. PUR1 bulls had greater (p<0.05) final weight (496.0 kg) than PUCA bulls (449.2 kg). However, there was no difference (p>0.05) between PUR1 and PUR2 (472.0 kg), and between PUR2 and PUCA. Hot carcass weight was similar (p>0.05) among the different genetic groups. Hot carcass dressing percentage was similar (p>0.10) between PUR1 (50.4%) and PUCA (53.8%), and higher (p<0.10) than PUR2 (48.6%). Cushion thickness was greater (p<0.05) in PUCA bulls (27.12 cm). The other parameters were similar (p<0.05) among the three genetic groups. Total lipid and cholesterol contents were higher (p<0.01) in PUR2. Moisture, ash and crude protein contents were similar (p>0.05) among the three genetic groups. Saturated fatty acid (SFA) levels were higher (p<0.10) in PUR1 and PUR2 (51.58% and 50.41%, respectively). Polyunsaturated fatty acid levels were higher (p<0.05) in PUR1 and PUCA (6.50% and 8.29%, respectively). N-6, n-3 and PUFA/SFA ratios were higher (p<0.05) in PUCA. MUFA and n-6/n-3 ratios were similar (p>0.05) among the different genetic groups.

Self-sustained n-Type Memory Transistor Devices Based on Natural Cellulose Paper Fibers

  • Martins, Rodrigo;Pereira, Luis;Barquinha, Pedro;Correia, Nuno;Goncalves, Goncalo;Ferreira, Isabel;Dias, Carlos;Correia, N.;Dionisio, M.;Silva, M.;Fortunato, Elvira
    • Journal of Information Display
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    • v.10 no.4
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    • pp.149-157
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    • 2009
  • Reported herein is the architecture for a nonvolatile n-type memory paper field-effect transistor. The device was built via the hybrid integration of natural cellulose fibers (pine and eucalyptus fibers embedded in resin with ionic additives), which act simultaneously as substrate and gate dielectric, using passive and active semiconductors, respectively, as well as amorphous indium zinc and gallium indium zinc oxides for the gate electrode and channel layer, respectively. This was complemented by the use of continuous patterned metal layers as source/drain electrodes.

Xanthomonas axonopodis pv. eucalyptorum pv. nov. Causing Bacterial Leaf Blight on Eucalypt in Brazil

  • Ferraz, Helvio Gledson Maciel;Badel, Jorge Luis;da Silva Guimaraes, Lucio Mauro;Reis, Bruna Paolinelli;Totola, Marcos Rogerio;Goncalves, Rivadalve Coelho;Alfenas, Acelino Couto
    • The Plant Pathology Journal
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    • v.34 no.4
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    • pp.269-285
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    • 2018
  • Bacterial leaf blight is a major disease of eucalypt, especially under nursery conditions. Different bacterial species have been associated with the disease in several countries, and despite its importance worldwide, it is not clear to date whether similar disease symptoms are caused by the same or by different etiological agents. In this study, 43 bacterial strains were isolated from blighted eucalypt leaves collected in different geographic areas of Brazil and inoculated onto a susceptible eucalypt clone. Polyphasic taxonomy, including morphological, physiological, biochemical, molecular, and pathogenicity tests showed that only certain strains of Xanthomonas axonopodis caused symptoms of the disease. Strains varied in their aggressiveness, but no correlation with geographic origin was observed. MLSA-based phylogenetic analysis using concatenated dnaK, fyuA, gyrB and rpoD gene sequences allocated the strains in a well-defined clade, corresponding to Rademarker's group RG 9.6. Inoculation of nineteen plant species belonging to seven botanical families with representative strain LPF 602 showed it to be pathogenic only on Eucalyptus spp, and Corymbia spp. Based on distinct biochemical and pathogenic characteristics that differentiate the eucalypt strains from other pathovars of the X. axonopodis species, here we propose their allocation into the new pathovar X. axonopodis pv. eucalyptorum pv. nov.

Comparative analysis of physicochemical properties of root perforation sealer materials

  • Orcati Dorileo, Maura Cristiane Goncales;Pedro, Fabio Luis Miranda;Bandeca, Matheus Coelho;Guedes, Orlando Aguirre;Villa, Ricardo Dalla;Borges, Alvaro Henrique
    • Restorative Dentistry and Endodontics
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    • v.39 no.3
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    • pp.201-209
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    • 2014
  • Objectives: This study evaluated the solubility, dimensional alteration, pH, electrical conductivity, and radiopacity of root perforation sealer materials. Materials and Methods: For the pH test, the samples were immersed in distilled water for different periods of time. Then, the samples were retained in plastic recipients, and the electrical conductivity of the solution was measured. The solubility, dimensional alteration, and radiopacity properties were evaluated according to Specification No. 57 of the American National Standards Institute/American Dental Association (ANSI/ADA). Statistical analyses were carried out using analysis of variance (ANOVA) and Tukey's test at a significance level of 5%. When the sample distribution was not normal, a nonparametric ANOVA was performed with a Kruskal-Wallis test (${\alpha}$ = 0.05). Results: The results showed that white structural Portland cement (PC) had the highest solubility, while mineral trioxide aggregate (MTA)-based cements, ProRoot MTA (Dentsply-Tulsa Dental) and MTA BIO ($\hat{A}$ngelus Ind. Prod.), had the lowest values. MTA BIO showed the lowest dimensional alteration values and white PC presented the highest values. No differences among the tested materials were observed in the the pH and electrical conductivity analyses. Only the MTA-based cements met the ANSI/ADA recommendations regarding radiopacity, overcoming the three steps of the aluminum step wedge. Conclusions: On the basis of these results, we concluded that the values of solubility and dimensional alteration of the materials were in accordance with the ANSI/ADA specifications. PCs did not fulfill the ANSI/ADA requirements regarding radiopacity. No differences were observed among the materials with respect to the pH and electrical conductivity analyses.

Optimization of Tannase Production by Aspergillus niger in Solid-State Packed-Bed Bioreactor

  • Rodriguez-Duran, Luis V.;Contreras-Esquivel, Juan C.;Rodriguez, Raul;Prado-Barragan, L. Arely;Aguilar, Cristobal N.
    • Journal of Microbiology and Biotechnology
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    • v.21 no.9
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    • pp.960-967
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    • 2011
  • Tannin acyl hydrolase, also known as tannase, is an enzyme with important applications in the food, feed, pharmaceutical, and chemical industries. However, despite a growing interest in the catalytic properties of tannase, its practical use is very limited owing to high production costs. Several studies have already demonstrated the advantages of solid-state fermentation (SSF) for the production of fungal tannase, yet the optimal conditions for enzyme production strongly depend on the microbial strain utilized. Therefore, the aim of this study was to improve the tannase production by a locally isolated A. niger strain in an SSF system. The SSF was carried out in packed-bed bioreactors using polyurethane foam as an inert support impregnated with defined culture media. The process parameters influencing the enzyme production were identified using a Plackett-Burman design, where the substrate concentration, initial pH, and incubation temperature were determined as the most significant. These parameters were then further optimized using a Box-Behnken design. The maximum tannase production was obtained with a high tannic acid concentration (50 g/l), relatively low incubation temperature ($30^{\circ}C$), and unique low initial pH (4.0). The statistical strategy aided in increasing the enzyme activity nearly 1.97-fold, from 4,030 to 7,955 U/l. Consequently, these findings can lead to the development of a fermentation system that is able to produce large amounts of tannase in economical, compact, and scalable reactors.

Improved Production of Medium-Chain-Length Polyhydroxyalkanoates in Glucose-Based Fed-Batch Cultivations of Metabolically Engineered Pseudomonas putida Strains

  • Poblete-Castro, Ignacio;Rodriguez, Andre Luis;Lam, Carolyn Ming Chi;Kessler, Wolfgang
    • Journal of Microbiology and Biotechnology
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    • v.24 no.1
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    • pp.59-69
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    • 2014
  • One of the major challenges in metabolic engineering for enhanced synthesis of value-added chemicals is to design and develop new strains that can be translated into well-controlled fermentation processes using bioreactors. The aim of this study was to assess the influence of various fed-batch strategies in the performance of metabolically engineered Pseudomonas putida strains, ${\Delta}gcd$ and ${\Delta}gcd-pgl$, for improving production of medium-chain-length polyhydroxyalkanoates (mcl-PHAs) using glucose as the only carbon source. First we developed a fed-batch process that comprised an initial phase of biomass accumulation based on an exponential feeding carbon-limited strategy. For the mcl-PHA accumulation stage, three induction techniques were tested under nitrogen limitation. The substrate-pulse feeding was more efficient than the constant-feeding approach to promote the accumulation of the desirable product. Nonetheless, the most efficient approach for maximum PHA synthesis was the application of a dissolved-oxygen-stat feeding strategy (DO-stat), where P. putida ${\Delta}gcd$ mutant strain showed a final PHA content and specific PHA productivity of 67% and $0.83g{\cdot}l^{-1}{\cdot}h^{-1}$, respectively. To our knowledge, this mcl-PHA titer is the highest value that has been ever reported using glucose as the sole carbon and energy source. Our results also highlighted the effect of different fed-batch strategies upon the extent of realization of the intended metabolic modification of the mutant strains.

Active-treatment effects of the Forsus fatigue resistant device during comprehensive Class II correction in growing patients

  • Cacciatore, Giorgio;Alvetro, Lisa;Defraia, Efisio;Ghislanzoni, Luis Tomas Huanc;Franchi, Lorenzo
    • The korean journal of orthodontics
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    • v.44 no.3
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    • pp.136-142
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    • 2014
  • Objective: To evaluate the active-treatment effects of the Forsus fatigue resistant device (Forsus) during comprehensive correction of Class II malocclusion in growing patients. Methods: Fifty-four patients (mean age, $12.5{\pm}1.2$ years) with Class II division 1 malocclusion were consecutively treated with fixed app-liances in combination with Forsus. Lateral cephalograms were analyzed at the beginning of the fixed treatment (T1), Forsus insertion (T2), its removal (T3), and end of the comprehensive therapy (T4). Statistical comparisons were carried out by repeated-measures ANOVA with Tukey's post-hoc test (p < 0.05). Results: The overall therapeutic effects were mainly dentoalveolar and occurred mostly during the active treatment with Forsus (T2-T3, mean duration = $0.5{\pm}0.1$ years). The overjet and overbite decreased significantly (-3.5 and -1.5 mm, respectively) and the molar relationship improved by 4.3 mm. These changes were associated with significant retroclination of the maxillary incisors ($-3.1^{\circ}$), proclination and intrusion of the mandibular incisors ($+5.0^{\circ}$ and -1.5 mm, respectively), and mesialization of the mandibular molars (+2.0 mm). Conclusions: Forsus had mainly dentoalveolar effects and contributed largely to the overall therapeutic outcome.

Brazilian Test of Concrete Specimens Subjected to Different Loading Geometries: Review and New Insights

  • Garcia, Victor J.;Marquez, Carmen O.;Zuniga-Suarez, Alonso R.;Zuniga-Torres, Berenice C.;Villalta-Granda, Luis J.
    • International Journal of Concrete Structures and Materials
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    • v.11 no.2
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    • pp.343-363
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    • 2017
  • The objective of this work was finding out the most advisable testing conditions for an effective and robust characterization of the tensile strength (TS) of concrete disks. The independent variables were the loading geometry, the angle subtended by the contact area, disk diameter and thickness, maximum aggregate size, and the sample compression strength (CS). The effect of the independent variables was studied in a three groups of experiments using a factorial design with two levels and four factors. The likeliest location where failure beginning was calculated using the equations that account for the stress-strain field developed within the disk. The theoretical outcome shows that for failure beginning at the geometric center of the sample, it is necessary for the contact angle in the loading setup to be larger than or equal to a threshold value. Nevertheless, the measured indirect tensile strength must be adjusted to get a close estimate of the uniaxial TS of the material. The correction depends on the loading geometry, and we got their mathematical expression and cross-validated them with the reported in the literature. The experimental results show that a loading geometry with a curved contact area, uniform load distribution over the contact area, loads projected parallel to one another within the disk, and a contact angle bigger of $12^{\circ}$ is the most advisable and robust setup for implementation of BT on concrete disks. This work provides a description of the BT carries on concrete disks and put forward a characterization technique to study costly samples of cement based material that have been enabled to display new and improved properties with nanomaterials.

ACCRETION-JET MODEL FOR THE HARD X-ray Γ - LX CORRELATION IN BLACK HOLE X-ray BINARIES

  • YANG, QI-XIANG;XIE, FU-GUO;YUAN, FENG;ZDZIARSKI, ANDRZEJ A.;GIERLINSKI, MAREK;HO, LUIS C.;YU, ZHAOLONG
    • Publications of The Korean Astronomical Society
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    • v.30 no.2
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    • pp.565-568
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    • 2015
  • In this work, we study the correlation between the photon index (${\Gamma}$) of the X-ray spectrum and the 2-10 keV X-ray luminosity ($L_X$) for black hole X-ray binaries (BHBs). The BHB sample is mainly from the quiescent, hard and intermediate states, with values of $L_X$ ranging from ${\sim}10^{30.5}$ to $10^{37.5}$ erg $s^{-1}$. We find that the photon index ${\Gamma}$ is positively or negatively correlated with the X-ray luminosity $L_X$, for $L_X$ above or below a critical value, ${\sim}10^{36.5}$ erg $s^{-1}$. This result is consistent with previous works. Moreover, when $L_X{\leq}{\sim}10^{33}$ erg $s^{-1}$, we found that the photon index is roughly independent of the X-ray luminosity. We interpret the above correlations in the framework of a coupled hot accretion flow - jet model. Besides, we also find that in the moderate-luminosity region, different sources may have different anti-correlation slopes, and we argue this diversity is caused by the different value of ${\delta}$, which describes the fraction of turbulent dissipation that directly heats electrons.