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Number of results: 14
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Abstract

In the last two decades several new concepts of photodetectors to improve their performance have been proposed. New strategies are especially addressed to the group of so called high-operating-temperature detectors where - apart from increasing of operating temperature - both the size and power consumption reduction is expected. In this paper a new strategy in the photo-detector design is presented - the barrier detectors: CnBn; CnBnN+, CpBn and unipolar barrier photodiodes. In spite of considering barrier detectors based on AIIIBV bulk compounds and type-II superlattices as having theoretically a better performance than those based on HgCdTe, the latter compound is also used to fabricate barrier detectors. Among many new applications of barrier detectors the detection of explosives can be extremely important due to an increased threat of terrorist attacks. This paper presents the status of the barrier detectors and compares the performance of mid-wave HgCdTe barrier detectors and unipolar barrier photodiodes.

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Authors and Affiliations

P. Martyniuk
W. Gawron
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Abstract

The aim of this work is to develop a numerical model capable of predicting the grain density in the Mg-based matrix phase of an AZ91/SiC composite, as a function of the total mass fraction of the embedded SiC particles. Based on earlier work in a range of alloy systems, we assume an exponential relationship between the grain density and the maximum supercooling during solidification. Analysis of data from cast samples with different thicknesses, and mass fractions of added SiCp, permits conclusions to be drawn on the role of SiCp in increasing grain density. By fitting the data, an empirical nucleation law is derived that can be used in a micro model. Numerical simulation based on the model can predict the grain density of magnesium alloys containing SiC particles, using the mass fraction of the particles as inputs. These predictions are compared with measured data.

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Authors and Affiliations

J. Lelito
H. Krawiec
V. Vignal
B. Gracz
P.L. Żak
M. Szucki
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Abstract

This paper presents the study of microstructure and properties of 8 mol% yttrium stabilized zirconia coating fabricated by Plasma Spray Physical Vapor Deposition technique on commercial pure titanium. The coating was characterized by X-ray diffraction, high resolution scanning electron microscope, profilometer, nanoindentation and nanomachining tests. The X-ray phase analysis exhibit the tetragonal Zr0.935Y0.065O1.968, TiO and α-Ti phases. The Rietveld refinement technique were indicated the changes of crystal structure of the produced coatings. The characteristic structure of columns were observed in High Resolutions Scanning Electron Microscopy. Moreover, the obtained coating had various development of surfaces, thickness was equal to 3.1(1) µm and roughness 0.40(7) µm. Furthermore, the production coatings did not show microcracks, delamination and crumbing. The performed experiment encourages carried out us to tests for osseointegration.

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Authors and Affiliations

J. Barczyk
G. Dercz
I. Matuła
M. Góral
J. Maszybrocka
D. Bochenek
W. Gurdziel
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Abstract

We used artificial hybridization to study the crossability of the noble fir (Abies procera) with Manchurian fir (A. holophylla) and Caucasian fir (A. nordmanniana), and found compatibility between A. procera of North American origin and the Asian species A. holophylla as evidenced by the 14% fraction of filled seeds obtained in A. procera × A. holophylla crossing. Crossing of A. procera with the Mediterranean species A. nordmanniana failed completely, producing only empty seeds.

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Authors and Affiliations

Andrej Kormuták
Božena Vooková
Terézia Salaj
Vladimír Čamek
Martin Galgóci
Peter Maňka
Peter Boleèek
Jaroslav Kobliha
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Abstract

This study aimed to evaluate the concentrations of α1-acid glycoprotein (AGP), haptoglobin (Hp), serum amyloid-A (SAA) and ceruloplasmin (Cp) in healthy and various diseased cats and establish reference intervals (RIs) for these acute phase proteins (APPs) in healthy cats. The animal material of the study consisted of 40 healthy cats and 152 cats with various diseases. The serum APPs in the diseased group were higher than those in the healthy group, and age affected Cp concentration in healthy cats. Also, the systemic inflammatory response syndrome (SIRS) positive (+) group had significantly higher AGP concentrations than the SIRS negative (-) group. In conclusion, this study contributes to the limited number of studies on RIs in serum APPs concentrations in healthy cats. The results of this study suggest that APPs are valuable diagnostic tools for identifying the inflammatory processes of various diseases, and AGP concentration could help determine the severity of the inflammatory condition.
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Authors and Affiliations

G.E. Tuna
1
B. Ulutas
1

  1. Department of Internal Medicine, Veterinary Faculty, Adnan Menderes University, Işıklı St. No: 805, 09020 Efeler/AYDIN09100 Aydın, Turkey
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Abstract

Selective deposition was performed on a micrometer trench pattern using a microcontact printing (μCP) process. Alkanethiols required for selective deposition were analyzed according to the carbon chain by linear sweep voltammetry (LSV). According to the LSV analysis, the effect of inhibiting Cu deposition depending on the length of the carbon chain was observed. During the Cu electrodeposition, the trench could be filled without voids by additives (PEG, SPS, JGB) in the plating solution. A μCP process suppressing the deposition of the sample was used for selective Cu electrodeposition. However, there was oxidation and instability of the sample and 1-hexadecanethiol in air. To overcome these problems, the μCP method was performed in a glove box to achieve effective inhibition.
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Bibliography

[1] P.C. Andricacos, C. Uzoh, J.O. Dukovic, J. Horkans, H. Deligianni, Damascene copper electroplating for chip interconnections, IBM Journal of Research and Development 42 (1998) 567-574.
[2] S.-Y. Chang, C.-W. Lin, H.-H. Hsu, J.-H. Fang, S.-J. Lin, Integrated Electrochemical Deposition of Copper Metallization for Ultralarge-Scale Integrated Circuits, Journal of The Electrochemical Society 151, C81 (2004).
[3] M.J. Kim, Y. Seo, H.C. Kim, Y. Lee, S. Choe, Y.G. Kim, S.K. Cho, J.J. Kim, Galvanostatic bottom-up filling of TSV-like trenches: Choline-based leveler containing two quaternary ammoniums, Electrochimica Acta 163, 174-181 (2015).
[4] V .S. Rao, C.T. Chong, D. Ho, D.M. Zhi, C.S. Choong, L.P.S. Sharon, D. Ismael, Y.Y. Liang, Development of High Density Fan Out Wafer Level Package (HD FOWLP) with Multi-layer Fine Pitch RDL for Mobile Applications, in: 2016 IEEE 66th Electronic Components and Technology Conference (ECTC), 1522-1529 (2016).
[5] F.I. Lizama-Tzec, L. Canché-Canul, G. Oskam, Electrodeposition of copper into trenches from a citrate plating bath, Electrochimica Acta, 56, 9391-9396 (2011).
[6] T.P. Moffat, J.E. Bonevich, W.H. Huber, A. Stanishevsky, D.R. Kelly, G.R. Stafford, D. Josell, Superconformal Electrodeposition of Copper in 500–90 nm Features, Journal of The Electrochemical Society 147, 4524 (2000).
[7] F.Q. Liu, T. Du, A. Duboust, S. Tsai, W.-Y. Hsu, Cu Planarization in Electrochemical Mechanical Planarization, Journal of The Electrochemical Society 153, C377 (2006).
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[9] F.B. Kaufman, D.B. Thompson, R.E. Broadie, M.A. Jaso, W.L. Guthrie, D.J. Pearson, M.B. Small, Chemical‐Mechanical Polishing for Fabricating Patterned W Metal Features as Chip Interconnects, Journal of The Electrochemical Society 13, 3460- 3465 (1991).
[10] N.B. Larsen, H. Biebuyck, E. Delamarche, B. Michel, Order in Microcontact Printed Self-Assembled Monolayers, Journal of the American Chemical Society 119, 3017-3026 (1997).
[11] S.H. Lee, W.-Y. Rho, S.J. Park, J. Kim, O.S. Kwon, B.-H. Jun, Multifunctional self-assembled monolayers via microcontact printing and degas-driven flow guided patterning, Scientific Reports 8, 16763 (2018).
[12] T.E. Balmer, H. Schmid, R. Stutz, E. Delamarche, B. Michel, N.D. Spencer, H. Wolf, Diffusion of alkanethiols in PDMS and its implications on microcontact printing (μCP), Langmuir 21, 622-632 (2005).
[13] M. Hasegawa, Y. Negishi, T. Nakanishi, T. Osaka, Effects of additives on copper electrodeposition in submicrometer trenches, Journal of The Electrochemical Society 152, C221 (2005)
[14] M.H. Schoenfisch, J.E. Pemberton, Air Stability of Alkanethiol Self-Assembled Monolayers on Silver and Gold Surfaces, Journal of the American Chemical Society 120, 4502-4513 (1998).
[15] N.T. Flynn, T.N.T. Tran, M.J. Cima, R. Langer, Long-term stability of self-assembled monolayers in biological media, Langmuir 19, 10909-10915 (2003).
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Authors and Affiliations

Jinyong Shim
1
ORCID: ORCID
Jinhyun Lee
1
ORCID: ORCID
Bongyoung Yoo
1
ORCID: ORCID

  1. Hanyang University, Department of Material Science & Chemical Engineering, Ansan, Korea
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Abstract

Phosphorothioate CpG oligodeoxynucleotides (ODN) are reported to be recognized by the membrane-bound TLR9 and trigger the MyD88-dependent up-regulation of Type I interferons and pro-inflammatory cytokines. Whether plasmids containing multiple CpG motifs stimulate the same signaling pathway is yet to be determined. The present results show that the CpG motifs enrich plasmid pUC18-CpG stimulates RAW 264.7 in vitro, mainly through the TBK1-mediated signaling pathway, causing the up-regulation of IFN-β, and pro-inflammatory cytokines TNF-α and IL-6. When pUC18-CpG is co-administered with the recombinant Echinococcus granulosus antigen, the antigen-specific antibody titers are markedly increased compared to the Quil-A adju- vanted group. Antigen specific cytokine quantification shows that cytokine profiles from the pUC18-CpG adjuvanted-group are switched to a Th1-biased immune response.

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Authors and Affiliations

J. Wu
Q. Chen
T. Xin
Y. Sun
H. Jia
S.H. Hou
X.Y. Guo
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Abstract

One of the actual challenges in tissue engineering applications is to efficiently produce as high of number of cells as it is only possible, in the shortest time. In static cultures, the production of animal cell biomass in integrated forms (i.e. aggregates, inoculated scaffolds) is limited due to inefficient diffusion of culture medium components observed in such non-mixed culture systems, especially in the case of cell-inoculated fiber-based dense 3D scaffolds, inside which the intensification of mass transfer is particularly important. The applicability of a prototyped, small-scale, continuously wave-induced agitated system for intensification of anchorage-dependent CP5 chondrocytes proliferation outside and inside three-dimensional poly(lactic acid) (PLA) scaffolds has been discussed. Fibrous PLA-based constructs have been inoculated with CP5 cells and then maintained in two independent incubation systems: (i) non-agitated conditions and (ii) culture with wave-induced agitation. Significantly higher values of the volumetric glucose consumption rate have been noted for the system with the wave-induced agitation. The advantage of the presented wave-induced agitation culture system has been confirmed by lower activity of lactate dehydrogenase (LDH) released from the cells in the samples of culture medium harvested from the agitated cultures, in contrast to rather high values of LDH activity measured for static conditions. Results of the proceeded experiments and their analysis clearly exhibited the feasibility of the culture system supported with continuously wave-induced agitation for robust proliferation of the CP5 chondrocytes on PLA-based structures. Aside from the practicability of the prototyped system, we believe that it could also be applied as a standard method offering advantages for all types of the daily routine laboratory-scale animal cell cultures utilizing various fiber-based biomaterials, with the use of only regular laboratory devices.

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Authors and Affiliations

Maciej Pilarek
Michał Wojasiński
Klaudia Godlewska
Aleksandra Kuźmińska
Katarzyna Dąbkowska
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Abstract

Hladnikia pastinacifolia RCHB., a narrow endemic, has an extremely restricted distribution in Trnovski gozd (Slovenia), despite the presence of many sites with suitable habitats. We compared the morphological traits of plants from different populations and habitats. The overall pattern showed that the smallest plants, with low fruit number, are found on Èaven (locus classicus or type locality); the largest individuals, with high fruit number, grow in the Golobnica gorge. As judged by plant size and seed set, the optimal habitats are screes. We used RAPD markers to estimate genetic variation between and within populations, as well as between and within the northern and the southern parts of the distribution area. Hladnikia showed only a low level of RAPD variability. AMOVA partitioned the majority of genetic diversity within selected populations. The low genetic differentiation between populations and their genetic depauperation indicates survival in situ, since the Trnovski gozd plateau most likely was a nunatak region in the southern Prealps during Pleistocene glaciations. Later range expansion of extant populations was limited by poor seed dispersal. We also analyzed the cpDNA trnL-F intergenic spacer to check whether the sequence is useful for studying the phylogenetic relationships of Hladnikia within the family Apiaceae (Umbelliferae). Our results support the assertion that H. pastinacifolia is an old taxon.

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Authors and Affiliations

Nina Šajna
Tatjana Kavar
Jelka Šuštar-Vozliè
Mitja Kaligariè
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Abstract

African swine fever (ASF) is an acute, hemorrhagic, and devastating viral infectious disease that causes important economic losses to the swine industry. Currently, there are no effective vaccines or drugs available. Epigenetic mechanisms, especially cytosine methylation of cytosine- -phosphate-guanine (CpG) islands, have a significant impact on the life cycle of several viruses. Hence, drugs targeting DNA methylation may potentially be used for the treatment of ASF. Here, we selected the inner core, core shell, inner membrane, capsid, and external envelope membrane, to analyze the characteristics of CpG islands in the ASF virus (ASFV) genomes. Furthermore, we analyzed the promoters and CpG islands in the upstream regions of these genes. Results showed that the CpG islands of seven genes were conserved in the genomes of two genotype of ASFV strains, whereas the CpG islands of other genes were relatively conserved (ASFV strains differed mainly in the quantity of CpG islands). The different distribution of CpG islands in the genomes of different ASFV strains may affect their methylation status, which may in turn affect the regulation of viral gene expression, leading to different clinical outcomes. In addition, the predicted promoter regions based on the upstream sequences of most genes overlapped with CpG island positions. Methylation of the binding sites of the promoter regions inhibits the binding of the transcription factors to the promoters, thus inhibiting the activation of the promoters and limiting the synthesis of viral proteins. The results of this study provide a basis for exploring new antiviral therapeutic strategies from an epigenetic perspective.
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Authors and Affiliations

Y.-Y. Yu
1
M.-S. X
2
Q. Liu
1

  1. Nanchong Key Laboratory of Disease Prevention, Control and Detection in Livestock and Poultry, Nanchong Vocational and Technical College, Nanchong 637131, China
  2. Chongqing Three Gorges Vocational College, Wanzhou 404155, China
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Abstract

Magnesium-based MMCs are widely used in structural-based applications due to their lightweight, high hardness, corrosion and wear resistance. Also, machining is an important manufacturing process that is necessary to ensure dimensional accuracy and produce intricate shapes. In this context, the machining of Magnesium based metal matrix composites is undertaken to study the impact of the cutting parameters on the machinability behaviour. In this work, turning of pure Mg/SiCp on a Lathe is done and an in-depth assessment on the machining forces, machined surface quality, chip microstructure, and tool morphology has been carried out using TiAlN coated tooling insert. The analysis revealed that the thrust force decreased due to the thermal softening of the matrix meanwhile the feed force also followed the similar trend at higher cutting speeds because of the minimized built-up edge and cutting depth whereas principal cutting force was inconsistent at higher cutting speeds. The surface finish was better at high cutting speed – low feed combination. The chip microstructure revealed that gross fracture propagation at the free surface and variations in the shear bands have occurred at different cutting speeds. Tool studies using SEM analysis revealed wear modes like chipping and built-up edge at low cutting speeds, but with a reduced impact at intermediate cutting conditions, whereas abrasion wear was observed predominantly in the tool nose at higher cutting speeds.
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Authors and Affiliations

K. Gobivel
1
ORCID: ORCID
K.S. Vijay Sekar
2
ORCID: ORCID

  1. KCG College of Technology, Karapakkam, Chennai, India
  2. Sri Sivasubramaniya Nadar College of Engineering, Kalavakkam, India
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Abstract

Humic acids, isolated from selected soils of Grønfjorden area (Spitsbergen) were investigated in terms of molecular composition and resistance of decomposition. The degree of soils organic matter stabilization has been assessed with the use of modern instrumental methods (nuclear magnetic resonance spectroscopy (CP/MAS 13C-NMR). Analysis of the humic acids showed that aromatic compounds prevail in the organic matter formed in cryoconites, located on the glaciers surfaces. The predominance of aliphatic fragments is revealed in the soils in tidal zone that form on the coastal terrace. This could be caused by sedimentation of fresh organic matter exhibiting low decomposition stage due to the harsh climate and processes of hydrogenation in the humic acids, destruction of the C-C bonds and formation of chains with a high hydrogen content. These processes result in formation of aliphatic fragments in the humic acids. In general, soils of the studied region characterizes by low stabilized soil organic matter which is indicated by low aromaticity of the HAs.

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Authors and Affiliations

Vyacheslav Polyakov
Elya Zazovskaya
Evgeny Abakumov
ORCID: ORCID
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Abstract

The methods arc described for determinations of Al, Fe, Ca, Mg, Ba, Cr, Mn, Ni, Cu, Zn, Pb, Cd, V and Sr in botanical, coal fly ash and soil samples by flame atomic absorption spectrometry (FAAS), and inductively coupled plasma atomic emission spectrometry (!CP-AES). Special attention has been paid to sample preparation, an important stage at which a sample is explored to contaminants. Results of the analysis of all samples arc discussed.
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Authors and Affiliations

Krystyna Srogi

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