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Blessing, Insko, Johnson and Mauretour gave a generalization of the domination number of a graph G called the ( t , r ) broadcast domination number which depends on the positive integer parameters t and r . In this setting, a v ∈ V is a broadcast vertex of transmission strength t if it transmits a signal of strength t − d ( u , v ) to every vertex u ∈ V with d ( u , v ) t . Given a set of broadcast vertices S ⊆ V , the reception at vertex u is the sum of the transmissions from the broadcast vertices in S . The set S ⊆ V is called a ( t , r ) broadcast dominating set if every vertex u ∈ V has a reception strength r ( u ) ≥ r and for a finite graph G the cardinality of a smallest broadcast dominating set is called the ( t , r ) broadcast domination number of G . In this paper, we consider the infinite triangular grid graph and define efficient ( t , r ) broadcast dominating sets as those broadcasts that minimize signal waste. Our main result constructs efficient ( t , r ) broadcasts on the infinite triangular grid graph for all t ≥ r ≥ 1 . Using these broadcasts, we then provide upper bounds for the ( t , r ) broadcast domination numbers for triangular matchstick graphs when ( t , r ) ∈ { ( 2 , 1 ) , ( 3 , 1 ) , ( 3 , 2 ) , ( 4 , 1 ) , ( 4 , 2 ) , ( 4 , 3 ) , ( t , t ) } .

Low residual stress in hydrogenated amorphous silicon-carbon (a-SixC1-x:H) films prepared by plasma-enhanced chemical vapor deposition (PECVD) at temperature range of 100–200 °C was obtained. Profilometry, Fourier transform infrared (FTIR) spectroscopy and atomic force microscopy (AFM) measurements were carried out to characterize the films. The residual stress of each deposited film was calculated using profilometry measurements and the Stoney equation. The results showed that the residual stress decreases as the power density is reduced, or the temperature or the silane/methane ratio are increased. There is a deposition pressure at around 750 mTorr at which low residual stress is promoted. The residual stress showed a correlation with the carbon incorporation in the form of C–Hn molecules. The residual stress depends on the deposition regime: assisted either by silane radicals (also known as “silane starving plasma” (SSP)) or by both silane and methane radicals. Considering that the carbon incorporation under SSP regime is more controlled, there is a higher probability of having low residual stress in this regime. In agreement with the characterization, the most favorable PECVD parameters were selected to obtain a-SixC1-x:H films with low residual stress (below 100 MPa) within the temperature range (100–200 °C). These results are useful in areas such as flexible electronic devices, implantable devices, microfluidic systems, and microelectromechanical systems, among others, in which the materials and the parameters of fabrication are degraded or modified by temperature above 200 °C. Keywords: Plasma-enhanced chemical vapor deposition, Hydrogenated amorphous silicon-carbon film, Residual stress, Fourier-transform infrared spectroscopy, Atomic force microscopy

In this work, we evaluate the performance of two biofunctionalization processes on silicon and hydrogenated amorphous silicon carbide (a-SiC:H). The biofunctionalization processes were designed to immobilize antibodies via non-specific physical adsorption or covalent attachment. The impact of the two surface types (crystalline and amorphous) on the resulting immunosensing layer is discussed in terms of the possible orientation, stability, and bioactivity of the immobilized antibodies. To evaluate the formation of active groups on the surface before and after the immobilization process, we used Fourier-transform infrared (FTIR) spectroscopy. On the other hand, to visualize the topography changes on the different surfaces with immobilized antibodies, we used atomic force microscopy (AFM). ELISA assay was conducted to obtain a quantitative parameter associated with the density of immobilized antibodies on the platforms. The results showed that the antibodies were immobilized on both platforms by any of the two immobilization mechanisms. The antigen capture did not show a direct relationship with the antibody estimation made by ELISA. According to the results, the a-SiC:H platforms by covalent attachment achieved the highest density of immobilized antibodies compared to silicon. However, its performance in the antigen detection assay was lower compared to silicon platforms. We concluded that the performance of the silicon platform was better in terms of its biofunctionalization and antigen detection. The orientation and structural integrity of the antibodies on the platforms was crucial to its performance on antigen detection.

In this work, the preparation of Zinc Oxide (ZnO) films by ultrasonic spray pyrolysis at low-temperature and its application in thin-film transistors (TFTs) are presented, as well, the impact of the active layer thickness and gate dielectric thickness in the electrical performance of the ZnO TFTs. A thinner active layer resulted in better transfer characteristics such as higher on/off-current ratio, while a thicker active layer resulted in better output characteristics. The ZnO films were deposited from 0.2 M precursor solution of Zinc acetate in methanol, using air as carrier gas on a hotplate at 200 °C. The ZnO films obtained at 200 °C were characterized by optical transmittance, Photoluminescence spectroscopy and X-ray diffraction.

The disruption of the intracellular Ca(2+) homeostasis of Leishmania mexicana represents a major target for the action of drugs, such as amiodarone and miltefosine. However, little is known about the mechanism of Ca(2+) entry to these cells. Here we show the presence of a Ca(2+) channel in the plasma membrane of these parasites. This channel has many characteristics similar to the human L-type voltage-gated Ca(2+) channel. Thus, Ca(2+) entry is blocked by verapamil, nifedipine and diltiazem while Bay K 8644 opened this channel. However, different to its human counterpart, sphingosine was able to open this channel, while other well known sphingolipids had no effect. This fact could have important pharmacological implications.

The objective of this work is to analyze the incidence of the time superior harmonics over the characteristics of a motor behavior. For this purpose, a computer program in Matlab was made, and it was possible, for different voltage supply waves, by the Fourier Series Analysis, to find the incidence of each harmonic over the motor parameters. Besides this, the machine general behavior can be obtained when all the harmonics of the highest order are present applying the superposition method. The importance of this work is focusing firstly on the possibility to simulate the effect of each harmonic that is present in the wave that is analyzed over the motor behavior. In second term, from the didactic point of view because it allows to compare the machine characteristics over the influence of the different time harmonics.

Selected PvDBP-derived synthetic peptides were tested in competition assays with HLA molecules in order to identify and evaluate their binding to a wide range of MHC class II molecules. Binding was evaluated as the peptide's ability to displace the biotinylated control peptide (HA306-318) and was detected by a conventional ELISA. Thus, one epitope for the HLA-DR1 molecule, two epitopes for the HLA-DR4 molecule, six epitopes for the HLA-DR7 molecule and three epitopes for the HLA-DR11 molecule displaying a high binding percentage (above 50%) were experimentally obtained. The in vitro results were compared with the epitope prediction results. Two peptides behaved as universal epitopes since they bound to a larger number of HLA-DR molecules. Given that these peptides are located in the conserved PvDBP region II, they could be considered good candidates to be included in the design of a synthetic vaccine against Plasmodium vivax malaria. © 2008 Elsevier Inc. All rights reserved.

Plasmodium falciparum thrombospondin-related apical merozoite protein (PTRAMP) has a thrombospondin related (TSR) domain which in many proteins has been reported as a fragment involved in pathogen-host and cell-interactions. Receptor-ligand studies using eighteen non-overlapping 20-aminoacid-long synthetic peptides from this protein were carried out to determine regions involved in parasite invasion of red blood cells (RBC). Two high activity binding peptides (HABPs) were determined, 33405 (21YISSNDLTSTNLKVRNNWEH40) and 33413 (180LEGPIQFSLGKSSGAFRINY199), presenting high dissociation constants and positive cooperativity. One of the HABPs displayed a modified P lasmodium e xport e lement (PEXEL), suggesting that this protein could be involved in the merozoite cytoplasmic reticulum, parasitophorous vacuole, red blood cell (RBC) cytosol, and probably infected RBC (iRBC) membrane transport of some other molecules and nutrients. Enzymatic treatment of RBCs increased HABP 33405 binding to them whilst it decreased HABP 33413 binding. Merozoite invasion assays revealed that HABPs have around 57% ability to inhibit new RBC invasion. Circular dichroism revealed the presence of possible α-helical elements in both HABPs structures. RBC binding interaction specificity and the presence of a PEXEL motif make these 2 HABPs good candidates for being included in further studies to develop a new multi-antigenic, multi-stage, subunit-based, chemically-synthesised, anti-malarial vaccine.

Synthetic 20-mer long non-overlapped peptides, from STEVOR protein, were tested in RBC binding assays for identifying STEVOR protein regions having high RBC binding activity and evaluating whether these regions inhibit Plasmodium falciparum in vitro invasion. Affinity constants, binding site number per cell and Hill coefficients were determined by saturation assay with high activity binding peptides (HABPs). HABP binding assays using RBCs previously treated with enzymes were carried out to study the nature of the receptor. The molecular weight of RBC surface proteins interacting with HABPs was determined by cross-linking assays and SDS-PAGE analysis. RBC binding assays revealed that peptides 30561 (41MKSRRLAEIQLPKCPHYNND60), 30562 (61PELKKIIDKLNEERIKKYIE80) and 30567 (161ASCCKVHDNYLDNLKKGCFG180) bound saturably and with high binding activity, presenting nanomolar affinity constants. HABP binding activity to RBCs previously treated with neuraminidase and trypsin decreased, suggesting that these peptides bound to RBC surface proteins and that such binding could be sialic acid dependent. Cross-linking and SDS-PAGE assays showed that the three HABPs specifically bound to 30 and 40 kDa molecular weight RBC membrane proteins. Peptides 30561, 30562 and 30567 inhibited P. falciparum in vitro invasion of red blood cells in a concentration-dependent way. Goat sera having STEVOR protein polymeric peptides antibodies inhibit parasite in vitro invasion depending on concentration. Three peptides localized in STEVOR N-terminal and central regions had high, saturable, binding activity to 30 and 40 kDa RBC membrane proteins. These peptides inhibited the parasite's in vitro invasion, suggesting that STEVOR protein regions are involved in P. falciparum invasion processes during intra-erythrocyte stage.

Conserved, high-activity, red blood cell binding malaria peptide 6786, from the HRP-I protein, having a random 3D structure as determined by 1H-NMR, was non-immunogenic and non-protection inducing when used as an immunogen in Aotus monkeys. Modifications made in its amino acid sequence were thus performed to render it immunogenic and protection inducing. Non-immunogenic, non-protection inducing modified peptide 13852 presented A2-H8 and K14-L18 helix fragments. Immunogenic, non-protection inducing modified peptide 23428 presented a short, displaced helix in a different region, whilst immunogenic, protection inducing peptide 24224 had 2 displaced helical regions towards the central region giving more flexibility to its N- and C-terminals. Immunogenic and protection inducing peptides bound with high affinity to HLA-DRB1* 0301 whilst others did not bind to any HLA-DRB1* purified molecule. Structural modifications may thus lead to inducing immunogenicity and protection associated with their capacity to bind specifically to purified HLA-DRB1* molecules, suggesting a new way of developing multi-component, subunit-based malarial vaccines.