Synthesis and Characterisation of Silver–2-Phenylenediamine–Cyclodextrin Nanomaterials

The spectral characteristics of 4, 4-diamino 3, 3-dimethyl biphenyl (DADMB) with various solvents, α-cyclodextrin (α-CD) and β-cyclodextrin (β-CD) at pH ~3, pH~7, were investigated using UV–visible, fluorescence, time-resolved fluorescence measurements, and PM3 computational methods. The DADMB–CD inclusion complexes and Cu:DADMB:CD nanomaterials were synthesized and characterized by DSC, SEM, FTIR, 1H NMR and XRD techniques. DADMB form 1:2 inclusion complex with CD. In the DADMB molecule, the horizontal bond lengths between the amino groups are higher than the CD cavity size suggest DADMB not fully encapsulate in the CD cavity. The powdered form of Cu nano, DADMB, Cu:DADMB:α-CD and Cu:DADMB:-CD nanomaterials were investigated by SEM, DSC, FTIR, XRD and 1H NMR. SEM picture clearly shows the morphological difference between copper nano, DADMB and the Cu:DADMB:-CD. The chemical shift value of DADMB protons are shifts to up field and down field and the peak intensities are very low in the nano copper with CD nanomaterials indicate that all the protons of DADMB are interacting with Cu nano and CD cavity protons.

Aims/Purpose: We recently introduced a new method for in vivo meibography in BALB/c mice. In this study, we compared the in vivo and ex vivo meibography in young and old mice.Methods: Eighteen male BALB/c mice (9 young mice and 9 old mice) were used in this study. We performed in vivo meibography on the upper and lower eyelids of the mice. Then, the mice were sacrificed, and the eyelids were excised en bloc. Ex vivo meibography was performed on the eyelids. For quantitative comparison, the number of meibomian glands(MG) identifiable in in vivo and ex vivo meibography was counted. For the same MG in lower eyelids of in vivo and ex vivo meibography, the horizontal length(HL), vertical length(VL), and area of the MG were measured and compared using image J.Results: The number of mean identifiable MG of in vivo and ex vivo meibography was 7.4 ± 0.8 and 11.6 ± 0.6 in upper eyelids (p < 0.001), and 8.4 ± 0.7 and 11.8 ± 0.9 in lower eyelids (p < 0.001), respectively. The mean HL of the same MG of in vivo and ex vivo meibography was 0.16 ± 0.03 and 0.17 ± 0.03 mm (p = 0.001). The mean VL of the same MG of in vivo and ex vivo meibography was 0.59 ± 0.08 and 0.69 ± 0.09 mm (p = 0.001). The mean area of the same MG of in vivo and ex vivo meibography was 0.14 ± 0.05 and 0.17 ± 0.05 mm2 (p = 0.001). The HL (r = 0.929, p < 0.001), VL (r = 0.737, p < 0.001), and area (r = 0.777, p < 0.001) of a MG of in vivo and ex vivo showed a strong positive correlation between them. The in vivo/ex vivo ratios of HL, VL, and area was 0.92 ± 0.09, 0.82 ± 0.05, and 0.82 ± 0.23 in young mice, and 0.95 ± 0.06, 0.89 ± 0.10, and 0.82 ± 0.16 in old mice. They showed no significant difference between young and old mice (p = 0.404, 0.102, and 0.984, respectively).Conclusions: This is the first study to compare quantitatively in vivo and ex vivo meibography in mice, the most common animal models for dry eye syndrome. In vivo meibography showed shorter HL, VL, and smaller area compared to ex vivo meibography, but there was a strong positive correlation between them. Because there was no significant difference in the in vivo/ex vivo ratio of HL, VL, and area between young and old mice, there is no problem comparing in vivo meibography between young and old mice.ReferenceHwang HS et al. A novel transillumination meibography device for in vivo imaging of mouse meibomian glands. Ocul Surf. 2021 Jan;19:201–209.

A series of dendritic multiporphyrin arrays (PZnTz-nPFB; n = 2, 4, 8) comprising a triazole-bearing focal zinc porphyrin (PZn) with a different number of freebase porphyrin (PFB) wings has been synthesized, and their photoinduced energy transfer process has been evaluated. UV/vis absorption, emission, and time-resolved fluorescence measurements indicated that efficient excitation energy transfer takes place from the focal PZn to PFB wings in PZnTz-nPFB's. The triazole-bearing PZn effectively formed host-guest complexes with anionic species by means of axial coordination with the aid of multiple C-H hydrogen bonds. By addition of various anionic guests to PZnTz and PZnTz-nPFB's, strong bathochromic shifts of PZn absorption were observed, indicating the HOMO-LUMO gap (ΔEHOMO-LUMO) of PZn decreased by anion binding. Time-resolved fluorescence measurements revealed that the fluorescence emission predominantly takes place from PZn in PZnTz-nPFB's after the addition of CN-. This change was reversible because a treatment with a silver strip to remove CN- fully recovered the original energy transfer process from the focal PZn to PFB wings.

The potential value of combining broadband and multispectral thermal infrared (TIR) data with multispectral and hyperspectral visible, near‐infrared (VNIR) and shortwave infrared (SWIR) data was investigated within the context of urban land‐cover classification. Using a case study of airborne Digital Airborne Imaging Spectrometer (DAIS) imagery of Strasbourg, France, the relative contribution of TIR wavelengths to classification accuracy was investigated for hyperspectral and simulated multispectral IKONOS, SPOT and Landsat Thematic Mapper (TM) bands. A support vector machines (SVM) classifier was used because this method was found to be very effective at handling the complex distributions of the heterogeneous land cover classes. The overall classification accuracy varied greatly with different band combinations. The inclusion of a single broad thermal band increased classification accuracy by as much as 20% for simulated IKONOS bands, but only 4% for hyperspectral VNIR and SWIR data. Adding multispectral TIR data raised the average accuracy approximately a further 10% for each band combination studied. Thermal wavelengths were found to be particularly useful for reducing the confusion between road and roof surfaces.

Purpose The purpose of this paper is to investigate the chest girth and height related to men’s upper body dimensions to develop men’s grading system for semi-customized clothing. Design/methodology/approach A data set of the 3,012 men between the age group of 18 and 59 years from 6th Size Korea was used in this study. The men’s upper body dimensions were tested in terms of five horizontal lengths, seven circumferences and seven vertical lengths. Experiment and data analysis were carried out with two methods: one is multiple linear regression with chest girth and height as each independent variable and the other is calculating variation among chest girth size groups and height size groups, respectively. Findings Regression analysis showed that some horizontal lengths are affected not only by chest girth, but also by height, and some vertical lengths are affected not only by height, but also by chest girth. In variation analysis it was found that the variation value for each part of the body is different and it was observed that with an increase in chest girth vertical length also increases. In variation analysis of height, it is found that some horizontal body dimensions and hip girth increase with an increase in height. In the comparison of upper body dimension variation among height groups with the size based on the chest girth, we found that a tall person who already has long vertical length is less affected by the increase in dimensions by increases in their horizontal girth than a short person. Originality/value The findings showed detailed numerical body shape changes according to chest girth and height, and it may be used as the basis for determining pattern grading values by chest girth or height.

The sol-to-gel transition was monitored via the use of time-resolved recording of the fluorescence emission of viscosity-sensitive probes. Two dyes were chosen for the study, water-soluble DASPMI and a hydrophobic BODIPY, and steady-state, time-resolved and time-tagged fluorescence measurements were performed. These techniques, coupled with the probes different solubility, allowed complementary fluorescence lifetime and intensity data to be obtained from the dyes introduced into the matrix-forming mixture to produce sol-gel derived monoliths. Two different precursors were used as examples. A hydrogel was formed from a commercially available gellan gum (Gelrite), and a glass-like monolith was formed using tetraethyl orthosilicate. Changes in fluorescence lifetime could be related to those in the local viscosity sensed by the probe. The combination of this type of probe with time-resolved measurements is extremely useful in monitoring the microscopic changes that occur during the sol-to-gel transition within this important class of materials.

Absorption spectra of crystalline films of carbon dioxide, nitrous oxide and carbonyl sulphide at liquid nitrogen temperature have been measured in the region 20 to 400 cm-1 using a Michelson interferometer. The two low-frequency bands appearing in carbon dioxide are interpreted as translational lattice modes and the single band in carbonyl sulphide as a torsional mode. The spectrum in each case is in agreement with predictions from the known crystal structure. A single broad band is observed in nitrous oxide and this is consistent with a disordered crystal structure.

This study aimed to evaluate different rates of basalt powder as a complementary source of mineral fertilization and its relationship with the nutritional status and agronomic traits of collard greens (Brassica oleracea var. acephala). The experiment was conducted in a completely randomized design, assessing six rates of basalt powder: T1 = 0; T2 = 2.0; T3 = 4.0; T4 = 6.0; T5 = 8.0; and T6 = 10.0 t/ha, with four replications. Three harvests of leaves were performed at approximately 30-day intervals, and the plant material was analyzed for nutritional status at harvest time, number of leaves per plant (NP), vertical length (VL), and horizontal length (HL), as well as fresh mass (FM) and dry mass (DM) of collard greens leaves. The application of basalt powder as a complementary source of mineral fertilization in collard greens cultivation promoted increases in VL and HL, with FM and DM of the leaves reaching maximum values of 33.11 and 23.40 cm, and 776.22 and 120.97 g/plant, respectively, up to the maximum applied rate of 6 t/ha. N, K, Ca, S, and Cu leaf contents increased, while that of P, Mg, Mn, Zn, B, and Mo levels decreased as basalt powder rates increased. Similarly, the accumulation of P, Mg, Mn, Zn, B, and Cu in the plant decreased with increasing basalt powder application. The use of basalt powder as a soil remineralizer to supplement mineral fertilization is feasible up to a dose of 6 t/ha.

Luminescence properties of Bi doped La2O3 powder phosphor

Photoluminescence of Cu(I)(PPh3)2(8-quinolinolate)

UV/vis absorption and time-resolved fluorescence measurements on alcoholic solutions of meso-tetrakis(4-sulfonatophenyl)porphyrin (TPPS(4)) in neutral and acid form have been performed as a function of the alcohol polarity. These solutions show a peculiar behavior that mimics porphyrin in confined water solutions. In alcohols, TPPS(4) exhibits a metastable phase showing the formation of new species in analogy with the confined water environment of AOT microemulsions. Various species have been detected at different pH values and on aging the solutions. Under neutral pH conditions, the porphyrin is present as free base monomer (S415) with a small amount of H-dimeric species (S400). On aging, the S415 leads to the formation of a new species (S423), which has been assigned as a J-type dimer of the neutral porphyrin. The species S400 and S423 are not present in bulk water solution but are typical of TPPS(4) in confined water. On decreasing pH, the S415 almost immediately converts into the diacid form (S438), which evolves toward red-shifted J-aggregates (S490) and blue-shifted H-aggregates (S420). On decreasing alcohol polarity, the kinetic evolution from fresh to aged solution and from the monomeric diacid species to H- and J-aggregates speeds up. Exploiting the amphiphilic character of short chain alcohols and widely varying their polarity, we were able to enhance in bulk conditions the peculiar behavior observed in close proximity to the microemulsion wall.

The nature of the heme environment in methemalbumin, the Fe(III) protoporphyrin IX (heme)-human serum albumin (HSA) complex, was investigated by optical spectroscopy. Comparison of the optical spectra of methemalbumin, ferro-hemalbumin in the absence and presence of 2-methylimidazole, and their carbon monoxide derivatives with horseradish peroxidase (HRP) and its corresponding derivatives indicates that histidine is not present in the first coordination sphere of heme in methemalbumin and that the protein is devoid of a well-defined heme cavity. The complex exhibits peroxidase activity by catalyzing oxidation of 2,2'-azinobis(3-ethylbenzthiazoline-6-sulfonate) by hydrogen peroxide. Its activity ( K(M)=433 microM, molar catalytic activity=0.33 s(-1)), however, is considerably lower compared to HRP, indicating differences in the heme environments. Fluorescence intensity decays of Trp214 in HSA and methemalbumin, best fitted to a three-exponential model, gave the lifetimes 7.03 ns (30%), 3.17 ns (38%), and 0.68 ns (32%) for HSA and 8.04 ns (1.7%), 2.42 ns (19.7%), and 0.64 ns (78.6%) for methemalbumin. These lifetime values were further confirmed by a model-independent maximum entropy method. Similarity in the lifetimes and variations in the amplitudes suggest that while conformational heterogeneity of HSA is unperturbed on heme binding, redistribution of the populations of the three conformations occurs and the sub-state associated with the shortest lifetime dominates the total population by approximately 80%. Decay associated spectra (DAS) indicate that the observed lifetime variation with wavelength is predominantly due to ground state heterogeneity, though solvent dipolar relaxation also contributes. Time-resolved fluorescence anisotropy measurements of the Trp214 residue yielded information on motion within the protein together with the whole protein molecule. The binding of heme did not affect the rotational correlation time of the albumin molecule (approximately 20 ns). However, the motion of tryptophan within the protein matrix increased by a factor of approximately 3 (0.46 ns to 0.15 ns). This indicates that while the overall hydrodynamic volume of the albumin molecule remained the same, tryptophan underwent a more rapid internal rotation because of the efficient energy transfer to the bound heme. Optical studies, analysis of lifetime measurements, DAS, and anisotropy measurements together suggest that heme binds to a surface residue. The rapid internal motion of Trp214 during its excited state lifetime for the approximately 80% populated conformer of methemalbumin allows the orientation factor, kappa(2), to approach the average value of 2/3. From the time-resolved fluorescence measurements and the energy transfer calculations on methemalbumin, a Trp214-heme distance of 22 A was deduced.

We have fabricated nanometer-sized channels, demonstrated a technique for the introduction of liquid into the channels, and carried out time-resolved fluorescence measurements of aqueous solutions. In this study, 330-nm- and 850-nm-sized channels were fabricated on fused-silica substrates by fast atom beam etching and hydrofluoric acid bonding methods. A liquid introduction method utilizing capillary action was demonstrated. The liquid introduction was observed under an optical microscope, and the liquid velocity during the introduction was analyzed by surface energy and macroscale hydrodynamics. The liquid velocity due to capillary action in the nanometer-sized channel seemed more than four times slower than the estimation. Then, aqueous solutions of rhodamine 6G (R6G), sulforhodamine 101 (SR101), and rhodamine B (RB) in the channels were measured by time-resolved fluorescence spectroscopy; spectra of the same solution in a 250-microm-sized channel were also measured as a reference for the macrospace. Although the fluorescence spectra in the 330-nm-, 850-nm- and 250-microm-sized channels agreed with one another, the fluorescent decays in the nanometer-sized channels were faster for R6G and SR101 and slower for RB than the respective decays in the 250-microm-sized channels. The results suggested the solutions had lower dielectric constants and higher viscosities in the nanometer-sized channels.

Time-resolved fluorescence measurement screening and sorting has been proven to be interesting for biological applications. Fluorescence lifetime (FLT) measurement provides additional information to the measurement of the intensity or polarization of the fluorescence emission. Furthermore, droplet microfluidics enables higher throughput than well plate readers. Few researches have been recently done about the microfluidic droplet sorting based on the fluorescence lifetime measurement. Some of the proposed solutions support high throughput but they do not extract the FLT directly from the fluorescence decay. In this paper, we present an alternative low-cost system for the microfluidic droplets sorting. We implemented a FLT measurement system based on the time-correlated single photon counting (TCSPC) technique on a cyclone V SoC-FPGA. For the excitation light source, we use a simple pulsed laser diode and a single photon avalanche diode (SPAD) as a photodetector. The optical system is an ad hoc microscope. The droplet generation is done with flow focusing technique in a PDMS-based microfluidics chip. This system was successfully tested in real-time at a droplet rate of more than 3000 droplets per second.

The high‐resolution model of elastic properties is of great significance for fine reservoir characterization and precise oil and gas exploration. However, it is difficult to obtain a satisfactory high‐resolution reservoir model with the existing technologies. In this paper, a novel high‐resolution stochastic modelling strategy based on the fast Fourier transform moving average is proposed. In this strategy, several structural parameters are optimized to improve the rationality of the stochastic model, including vertical autocorrelation length, horizontal autocorrelation length, roughness factor and angle parameter. Among them, the optimization of the vertical autocorrelation length is crucial for vertical high‐resolution modelling. To this end, a nonlinear optimal inversion strategy of the vertical autocorrelation length is designed based on the idea of minimizing the spectral Jensen–Shannon divergence between the modelling result and the logging curve. However, nonlinear inversion is usually unstable, so it is necessary to introduce a regularization operator in the inversion to improve the stability. Considering that the heterogeneity of the subsurface medium is consistent or gradual within the stratums, but discontinuous and abrupt at the interfaces, edge‐preserving regularization is applied to obtain a blocky estimation of the vertical autocorrelation length. The optimal estimation experiment of the vertical autocorrelation length based on the measured logging data shows that the edge‐preserving regularization significantly improves the stability of the nonlinear optimal inversion, and blocky estimation results with sharp edges are obtained. Then, the optimized vertical autocorrelation length and the other structural parameters are applied to fast Fourier transform moving average modelling on an actual reservoir profile. The result shows that the resolution of the model is significantly improved, which realizes the fine reservoir characterization. In addition, the optimized structural parameters effectively constrain the small‐scale heterogeneity and ensure the rationality of the stochastic model.