Maximum TF Research Articles

Design and investigation of targeting agent orientation and density on nanoparticles for enhancing cellular uptake efficiency.

The design of targeting agent-conjugated systems is attracting much attention in cell targeted delivery and cancer therapy. However, quantitative study of the ligand density and binding efficiency is still limited due to the technical matters and tedious work involved. In this article, benzoboroxole-modified core-shell magnetic nanoparticles (MSP-AOPB NPs) as a drug carrier model were fabricated and transferrin (Tf) was immobilized on the nanoparticle surface in a site-oriented manner (Tf-MSP-AOPB NPs). The preparation conditions were investigated in detail to optimize the Tf binding efficiency. A suitable reaction temperature, time or initial feeding amount could significantly increase the Tf binding amount. The maximum Tf binding amount on the MSP-AOPB NPs was 184 mg g-1, and the targeting ligand density on the surface could be well controlled by simply adjusting the reaction conditions. In vitro studies demonstrated the excellent Tf-mediated targeting ability and enhanced cellular uptake efficacy by varying the ligand density. The optimal ligand binding amount for achieving the highest cellular uptake efficiency was 94 mg Tf/g, which corresponds to a ligand binding density of about 0.05 Tf/nm2, and the binding efficiency of conjugation was higher than 90%. Moreover, Tf-MSP-AOPB NPs prepared by a site-oriented conjugation strategy showed the best cell targeting ability, and their cellular uptake amount was 25 and 127 times higher than that of physical adsorption and EDC/NHS coupling reaction in HepG2 cells, respectively. This study provides a facile site-oriented bioconjugation technique for different kinds of antibodies, and a suitable ligand density can be easily attained to enhance the cellular uptake efficacy, which shows great significance for targeted delivery and cancer therapy.

A numerical study on free-fall of a torus with initial inclination angle at low Reynolds numbers

In this study, the sedimentation of a torus is studied numerically over a range of Reynolds number spanning 10 ≤ ReT≤ 90. The three-dimensional governing equations are solved using the fluid–structure interaction version of the SVD-GFD method on a hybrid Cartesian-cum-meshless grid. The torus has a fixed aspect ratio AR = 2, and is set to fall along the negative x direction at an initial inclination angle θ0, in the range of 0 ≤θ0≤ 80°. The flow behavior induced by the falling torus is characterized by the far field vortex sheet and the near field recirculation zone. At a given ReT, the flow reaches the same terminal state and the torus maintains the same final state, orientation and terminal velocity, regardless of θ0. The torus initially experiences a zigzag motion (along the x and z directions) in the global frame and the pitch motion in its body frame, which are more obvious at larger ReT and θ0. The offset of the torus centroid in the z direction between the initial and terminal states increases with increasing ReT and θ0 because of the θ0 effect. The falling time (Tf) for the torus traveling along the same distance in the x direction decreases with increasing θ0 when ReT≤ 50. However, when ReT > 50, Tf initially increases and then decreases with increasing θ0, with the maximum Tf occurring at θ0≈ 60°. A lift-like force is generated in the positive x direction due to the translational torus motion in the z direction, which originates from the pressure. This force is most pronounced at θ0≈ 60° for ReT > 50, which thus significantly decelerates the falling speed of the torus and increases Tf.

Minimum diameter and tF (f, q)

For given integer e and q, let p(e, q) (res. C(e, q)) indicate to (MDe-PD). The maximum diameter deleting e edges from a connected graph of diameter q is f(e, q), the maximum number TF (f, q) of edges that have to be delete from a path q. In our study show construction p(7, 8k – 10) = k for k ≥ 3 And p(7, q′) = k for k ≥ 3 and q′ = 8k - 6, where e and q are positive integer also show that f (4, q) = 5q - 4 where q ≥ 4 and f (7, q) = 8q - 10 where q ≥ 5. Also and Where f (e, q) ≥ (e + 1) q - 2e + 4

Phytoremediation of mercury-contaminated soils by Jatropha curcas

Jatropha curcas plants species were tested to evaluate their phytoremediation capacity in soils contaminated by different levels of mercury. The experimental treatments consisted of four levels of mercury concentrations in the soil – T0, T1, T5, and T10 (0, 1, 5, and 10μg Hg per g soil, respectively). The total mercury content absorbed by the different plant tissues (roots, stems and leaves) was determined during four months of exposure. The growth behavior, mercury accumulation, translocation (TF) and bioconcentration (BCF) factors were determined. The different tissues in J. curcas can be classified in order of decreasing accumulation Hg as follows: roots>leaves>stems. The highest cumulative absorption of the metal occurred between the second and third month of exposure. Maximum TF was detected during the second month and ranged from 0.79 to 1.04 for the different mercury concentrations. Values of BCF ranged from 0.21 to 1.43. Soils with T1 showed significantly higher BCF (1.43) followed by T10 (1.32) and T5 (0.91), all of them at the fourth month. On the other hand TFs were low (range 0.10–0.26) at the en of the experiment. The maximum reduction of biomass (16.3%) occurred for T10 (10μg Hg g−1). In sum, J. curcas species showed high BCFs and low TFs, and their use could be a promising approach to remediating mercury-contaminated soils.

Hormesis phenomena under Cd stress in a hyperaccumulator—Lonicera japonica Thunb

A hydroponic experiment was carried out to investigate possible hormetic response induced by cadmium (Cd) in a potential hyperaccumulator-Lonicera japonica Thunb. The results showed that Cd at low concentrations induced a significant increase in plant growth, leaf water content and content of photosynthetic pigments in L. japonica, but decreased them at high concentrations, displayed inverted U-shaped dose response curves, confirming a typical biphasic hormetic response. The U-shaped dose response curves were displayed in malondialdehyde (MDA) and electrolyte leakage in leaves at low doses of Cd, indicating reduce oxidative stress and toxic effect. The increase of superoxide dismutase (SOD) and catalase (CAT) activities was observed along with the increased Cd concentration, indicative of increase in anti-oxidative capacity that ensures redox homeostasis is maintained. After 28 days exposure to 10 mg L(-1) Cd, stem and leaf Cd concentrations reached 502.96 ± 28.90 and 103.22 ± 5.62 mg kg(-1) DW, respectively and the plant had high bioaccumulation coefficient (BC) and translocation factor (TF'). Moreover, the maximum TF value was found at 2.5 mg L(-1) Cd treatment, implying that low Cd treatment improved the ability to transfer Cd from medium via roots to aerial structures. Taking together, L. japonica could be considered as a new plant to investigate the underlying mechanisms of hormesis and Cd tolerance. Our results suggest that hormetic effects should be taken into consideration in phytoremediation of Cd-contaminated soil.

Effects of the simultaneous application of potassium and calcium on the soil-to-Chinese cabbage transfer of radiocesium and radiostrontium

Pot experiments were carried out in a greenhouse to investigate how effectively the transfer of radiocesium and radiostrontium from soil to Chinese cabbage could be reduced by applying K and Ca simultaneously to the soil. The sources of these elements were KCl and Ca(OH) 2 at agrochemical grades. Varying dosages of K and Ca were tested for an acid loamy soil treated with a mixed solution of 137Cs and 85Sr at two different times – 3 d before sowing and 32 d after sowing. For the pre-sowing deposition, the soil-to-plant transfer of 137Cs decreased sharply with increasing dosages of K and Ca (K/Ca, g m −2) from 4.8/46 up to 22.4/215 but the 85Sr transfer had the greatest reduction at a dosage of 12.8/123. At this dosage, an about 60% reduction occurred for each radionuclide. Plant growth was inhibited from the dosage of 22.4/215, above which all the plants died young. Both dosages of 4.8/46 and 12.8/123 tested following the growing-time deposition produced around 95% reductions for 137Cs and 50% reductions for 85Sr. In the second year after the 12.8/123 applications, the effects for 85Sr were almost the same as in the first year, whereas those for 137Cs were diminished slightly for the pre-sowing deposition and markedly for the growing-time deposition. Considerably (K) or slightly (Ca) higher doses than 12.8/123 would be allowable for the maximum TF reductions achievable without a growth inhibition.

Dental fluorosis and dental caries among 12‐yr‐old children from high‐ and low‐fluoride areas in Lithuania

We investigated the prevalence and severity of dental fluorosis, and the occurrence of dental caries, among 12-yr-old children from high- and low-fluoride areas in a country with high caries figures and a developing oral healthcare system. The sample included a total of 600 lifetime residents from high-fluoride (HF; 1.7-2.2 ppm) and low-fluoride (LF; 0.2 ppm) areas in Lithuania. The diagnoses of dental fluorosis followed the Thylstrup-Fejerskov Index (TF), and a diagnosis of dental caries followed the World Health Organization criteria. In the HF area, 66% of the 12-yr-old children had dental fluorosis (TF score > 0) compared with 4% in the LF area. The maximum TF severity scores were 7 and 3, respectively. The mean number of teeth with fluorosis was 4.5 [95% confidence interval (CI) = 4.0, 5.0] for the HF group and 0.2 (95% CI = 0.1, 0.2) for the LF group. In the HF group, 72% had a decayed, missing or filled teeth (DMFT) score of > 0, compared with 87% in the LF group. The mean DMFT was 2.0 (95% CI = 1.8, 2.3) in the HF group and 3.5 (95% CI = 3.2, 3.8) in the LF group. Current untreated caries (DT) occurred (DT >0) in half of both the HF and LF groups. Regardless of the concentration of fluoride in the drinking water, the prevalence of past (DMFT > 0) and present (DT > 0) caries was high, calling for more emphasis on the prevention of tooth decay in countries, such as Lithuania, with high caries figures and a developing oral healthcare system.

LOW TEMPERATURE LINEAR DYNAMICAL SUSCEPTIBILITY OF THE ISING SPIN GLASS IN A TRANSVERSE FIELD

Low-temperature equilibrium dynamical behavior of the linear ac susceptibility in d-dimensional Ising spin glass with short-range interactions between spins in transverse field is investigated in terms of droplet model. The real part of linear ac susceptibility [Formula: see text] as functions of temperature T and frequency of external ac field ω is calculated. Frequency and temperature dependence of [Formula: see text] shows a glassy behavior. For instance, we find a broad maximum for [Formula: see text] which shifts towards higher temperatures with increasing frequency of ac-field. The temperature of maximum Tf(ω) depends on frequency and increases with frequency up to the magnitude where [Formula: see text] starts to decrease. A qualitative agreement of our calculations with experimental data, for example, in quantum dipole magnet LiHoxY1-xF4 and proton glasses, is found.

97/00642 Lysimeter studies of nitrogen leaching potential in wetland peats and clays in south-west Britain

Pot experiments were carried out in a greenhouse to investigate how effectively the transfer of radiocesium and radiostrontium from soil to Chinese cabbage could be reduced by applying K and Ca simultaneously to the soil. The sources of these elements were KCl and Ca(OH)2 at agrochemical grades. Varying dosages of K and Ca were tested for an acid loamy soil treated with a mixed solution of 137Cs and 85Sr at two different times – 3 d before sowing and 32 d after sowing. For the pre-sowing deposition, the soil-to-plant transfer of 137Cs decreased sharply with increasing dosages of K and Ca (K/Ca, g m−2) from 4.8/46 up to 22.4/215 but the 85Sr transfer had the greatest reduction at a dosage of 12.8/123. At this dosage, an about 60% reduction occurred for each radionuclide. Plant growth was inhibited from the dosage of 22.4/215, above which all the plants died young. Both dosages of 4.8/46 and 12.8/123 tested following the growing-time deposition produced around 95% reductions for 137Cs and 50% reductions for 85Sr. In the second year after the 12.8/123 applications, the effects for 85Sr were almost the same as in the first year, whereas those for 137Cs were diminished slightly for the pre-sowing deposition and markedly for the growing-time deposition. Considerably (K) or slightly (Ca) higher doses than 12.8/123 would be allowable for the maximum TF reductions achievable without a growth inhibition.

Effects of Rotation on Tubular Flames in an Axisymmetric Flow Field.

Using an axisymmetric swirl-type burner with eight inlet slits, the effects of rotation on the structure and characteristics of tubular flames have been investigated for lean methane/air mixtures.Results show that with increasing intensity of rotation, (1) the flame diameter increases and the thickness of the luminous zone decreases, (2) the fuel concentration at extinction decreases, i. e., the stable region expands, (3) the radial temperature distribution becomes an M-shaped profile, and the maximum temperature Tf increases while the local minimum temperature Tc at the center decreases, and (4) the values of Tf and Tc vary in a complicated manner in the axial direction. These results are almost consistent with those of our previous experiment, and hence, it is confirmed that the flame structure and the flame characteristics are affected by rotation. As for these phenomena, several mechanisms such as pressure diffusion, radiative heat loss, viscous energy dissipation, and energy recirculation including diffusion of radical species have been proposed. The present experimental results provide the first, basic information on this practically important phenomenon, i. e., the extension of flammable range by rotation.

Scaling laws for laser driven exploding pusher targets

An analytic model based on shock waves is used to describe the maximum density rho F, maximum temperature TF and minimum radius RF obtained in the laser driven implosion of a gas filled spherical shell target of shell thickness Delta T, shell radius R and initial gas density rho 1. The scaling behaviour rho F approximately rho 125/, rho FRf approximately rho 135/R and TF approximately ( alpha E0/M) rho 1-25/, is obtained, where E0 is the laser energy, M is the shell mass, and alpha is the hydrodynamically useful fraction of the laser energy. Instantaneous uniform heating of the shell is assumed in order to describe implosions of the 'exploding pusher' type.

Initiation and Progress of Scoring Failure on Cylindrical Involute Gears

Distributions of flash temperature Tf of on tooth flanks of spur and helical gears were calculated. The concentration of Tf at the beginning point of contact on leading side edge of tooth and at the ending point of contact on trailing side edge of tooth was found on helical gears, and the maximum Tf appeared on helical gears of small overlap ratio. By computer simulation for progress of scoring and by tooth flank observation of gears scored on test bench, the fashion of scoring progress on tooth and it proceeds in longitudinal direction on tooth flank of approaching contact, and then it occurs at the ending point of contact on trailing side edge of tooth and it proceeds on tooth flank of recess-contact in counter longitudinal direction.