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Abstract: Ab initio localized molecular orbital theory (GAMESS program) has been used to evaluate the effects of a second cation on nonlinear optical properties of tellurium oxide based glasses. Calculations were performed on [H n TeO3A3− n ]+ (n =0–3) molecules with alkali cations (A=Li, Na). Results of the calculations on optimized structures show that the effects of the second cation on the nonlinear optical properties are significant and related to the geometric modification of the structural unit. However, the introduction of the second cation induces an increase of both linear polarizability and second hyperpolarizabilty whereas experiments show the opposite, second hyperpolarizabilty is much more affected by the introduction of the second cation. Such calculations have to be performed on bigger size clusters in which the introduction of a second cation implies breaking a Te–O–Te bridge. [Copyright &y& Elsevier]

Abstract: Ab initio calculations of the non-linear optical properties for the TeO4 and TeO3 structural units in TeO2-based glasses are presented. Time-dependent Hartree–Fock calculation below the frequency of ∼400THz (750nm) shows that the shorter wavelength of the light injected should lead to the higher non-linear optical responses in both TeO4 and TeO3 structural units. Static finite-field calculation with the localized molecular orbital analysis classifies the second hyperpolarizability by the electron pairs assigned to the chemical bonds. This analysis suggested that the lone pair of electrons on the Te atom is a key to the non-linear optical properties of the TeO2-based glasses and that the TeO4 structural unit is responsible for the higher non-linear optical properties rather than the TeO3. [Copyright &y& Elsevier]

Examines the surface structures of the tellurium/nickel (111) system by using reflection high-energy electron diffraction combined with X-ray and ultraviolet photoelectron spectroscopies. Characterization of temperature phases; Adsorption of tellurium on nickel substrate; Mathematical formulas for tellurium/nickel surface characterization.

Abstract: The Effect of Si addition on In2O3 crystallization in a soda-boro-aluminosilicate glass was investigated. Si was found to be an essential component for obtaining glass material because the Si-free batch did not vitrify under the same condition. Transmission electron microscopy measurements on the glasses synthesized revealed that In2O3 particles with diameter 5nm size precipitated by an annealing for 3h at more than 550°C and their size increased with an increase of heat-treatment temperature. From the X-ray photoelectron spectroscopy measurement, the binding energy of In2O3 for as prepared glass shifted to higher binding energy after annealing in air. The band gap of In2O3 particles decreased from 3.9eV for as prepared glass samples to 2.6eV for the glass sample annealed at 600°C. [Copyright &y& Elsevier]

The glass forming capability, glass structural organization and optical properties have been examined in rare-earth doped oxyfluoride zinc tellurite glass system. As a function of composition, differential thermal analysis, vibrational spectra, optical absorption, spontaneous emission and lifetime measurements have been analyzed in term of fluorine influence. The bulk composition variation and addition of fluoride compounds in tellurite glasses result among others, broad emission spectra compared to silicate glasses, in improved emission lifetime and slight difference in relative band intensities compared to pure oxide glass. [Copyright &y& Elsevier]

Bilateral renal denervation (RDN) decreases arterial pressure (AP) or delays the development of hypertension in spontaneously hypertensive rats (SHR), but whether bilateral RDN significantly modifies urine output function during baroreflex-mediated acute AP changes remains unknown. We quantified the relationship between AP and normalized urine flow (nUF) in SHR that underwent bilateral RDN (n = 9) and compared the results with those in sham-operated SHR (n = 9). Moreover, we examined the acute effect of an angiotensin II type 1 receptor blocker telmisartan (2.5 mg/kg) on the AP-nUF relationship. Bilateral RDN significantly decreased AP by narrowing the response range of the total arc of the carotid sinus baroreflex. The slopes of nUF versus the mean AP (in μL·min -1 ·kg -1 ·mmHg -1 ) in the sham and RDN groups under baseline conditions were 0.076 ± 0.045 and 0.188 ± 0.039, respectively; and those after telmisartan administration were 0.285 ± 0.034 and 0.416 ± 0.078, respectively. The effect of RDN on the nUF slope was marginally significant (P = 0.059), which may have improved the controllability of urine output in the RDN group. The effect of telmisartan on the nUF slope was significant (P < 0.001) in the sham and RDN groups, signifying the contribution of circulating or locally produced angiotensin II to determining urine output function regardless of ongoing renal sympathetic nerve activity., (© 2024. The Author(s), under exclusive licence to The Japanese Society of Hypertension.)

We examined urine excretion during primary acute sympathetic activation (PASA) in anesthetized Wistar-Kyoto rats. Since arterial pressure (AP) changes with sympathetic nerve activity (SNA) during PASA, urine excretion reflects a neurally mediated antidiuretic effect combined with an effect of pressure diuresis. We hypothesized that preventing AP changes under PASA would enable the direct estimation of the neurally mediated antidiuretic effect alone. We changed the isolated carotid sinus pressure stepwise from 60 to 180 mmHg and compared the relationship of normalized urine flow (nUF, urine flow normalized by body weight) versus SNA between conditions allowing and preventing baroreflex-mediated changes in the mean AP. The slope of the SNA-nUF relationship was [Formula: see text]nUF var = 0.444 ± 0.074 μL·min -1 ·kg -1 ·% -1 when the mean AP was variable, whereas it was [Formula: see text]nUF fix = -0.143 ± 0.032 μL·min -1 ·kg -1 ·% -1 when the mean AP was fixed at 100 mmHg ( n = 7 rats). The slope associated with the effect of pressure diuresis alone, calculated as [Formula: see text]nUF var - [Formula: see text]nUF fix , was 0.586 ± 0.105 μL·min -1 ·kg -1 ·% -1 . Hence, the potency of the neurally mediated antidiuretic effect |[Formula: see text]nUF fix |/([Formula: see text]nUF var - [Formula: see text]nUF fix ) was 0.235 ± 0.014 relative to the effect of pressure diuresis under PASA. Our findings would aid an integrative understanding of the effects of renal hemodynamic and sympathetic modulations on urine output function.

We examined urine excretion during primary acute sympathetic activation (PASA) in Wistar-Kyoto rats with myocardial infarction (MI). The rats underwent unilateral renal denervation (RDN) 7 weeks after coronary artery ligation. 4-10 days later, an acute experiment was performed under anesthetized conditions (n = 8 rats). Isolated carotid sinus pressure was changed stepwise from 60 to 180 mmHg, and the relationship between the arterial pressure (AP) and the normalized urine flow (nUF, urine flow normalized by the body weight) was examined. After obtaining the control data, an angiotensin II type 1 receptor blocker telmisartan (2.5 mg/kg) was intravenously administered. The effects of RDN, telmisartan, and heart weight (biventricular weight) on the relationship between AP and nUF were examined using multiple regression analyses. Regarding the slope of nUF versus AP (nUF slope ), the constant term of the regression was positive (0.315 ± 0.069 μL·min -1 ·kg -1 ·mmHg -1 ), indicating that nUF increased with AP. The heart weight had a negative effect on nUF slope (P < 0.05), suggesting that the severity of MI was associated with the impairment of urine excretion. Telmisartan increased nUF slope by 0.358 ± 0.080 μL·min -1 ·kg -1 ·mmHg -1 (P < 0.001), whereas RDN had no significant effect on this parameter. The results indicate that unilateral RDN was unable to abolish the effect of the renin-angiotensin system on urine excretion during PASA. Circulating or locally produced angiotensin II, rather than ongoing renal sympathetic nerve activity, played a dominant role in the impairment of urine excretion during PASA in rats with chronic MI., (© 2022. Springer Japan KK, part of Springer Nature.)

Primary acute sympathetic activation (PASA) causes a subsequent arterial pressure (AP) elevation. In this case, an antidiuretic effect via the renal innervation and pressure diuresis can act antagonistically on the kidneys. We examined the effect of PASA on urine output in spontaneously hypertensive rats (SHR) 4-7 days after unilateral renal denervation (RDN) (n = 9). The slope of the plot of urine flow versus AP was positive (0.120 ± 0.031 μL min -1  kg -1 mmHg -1 ) on the intact side, but it was less than 1/3 of the slope observed previously in normotensive Wistar-Kyoto rats (WKY). RDN did not normalize the slope of urine flow versus AP (0.179 ± 0.025 μL min -1 kg -1 mmHg -1 , P = 0.098 versus the intact side). The urine flow at the operating point of the AP tended to be greater on the denervated than the intact side (29.0 ± 1.8 vs. 25.3 ± 1.9 μL min -1 kg -1 , P = 0.055). The percent increase (17.2 ± 7.2%) was not different from that observed previously in WKY. Although high-resting sympathetic nerve activity is prerequisite for maintaining hypertension in SHR, the effect of sympathetic innervation on the urine output function was not greater than that in WKY.

Primary acute sympathetic activation (PASA) can increase arterial pressure (AP). Under this situation, the kidneys may receive mutually opposing influences from sympathetic activation: a direct anti-diuretic effect via the renal innervation and pressure diuresis. We examined whether PASA would reduce urine output regardless of the AP elevation. We also examined the impact of renal denervation (RDN) on urine output during PASA. The experiment was performed on rats 3 to 9 days after unilateral RDN (n = 10). Under anesthesia, systemic sympathetic nerve activity (SNA) was varied over a wide range via the carotid sinus baroreflex. The slope of urine flow versus SNA was positive (0.252 ± 0.052 μL·min -1 ·kg -1 · % -1 ) on the intact side, and it was greater on the denervated side (0.331 ± 0.069 μL·min -1 ·kg -1 · % -1 , P < 0.05). In conclusion, urine output change was an effect of elevated AP during PASA. Nevertheless, RDN was able to augment pressure diuresis during PASA.

Considering the recent breakthroughs in the synthesis of novel two-dimensional (2D) materials from layered bulk structures, ternary layered transition metal borides, known as MAB phases, have come under scrutiny as a means of obtaining novel 2D transition metal borides, the so-called MBenes. Here, based on a set of phonon calculations, we show the dynamic stability of many Al-containing MAB phases, MAlB (M = Ti, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Tc), M2AlB2 (Sc, Ti, Zr, Hf, V, Cr, Mo, W, Mn, Tc, Fe, Rh, Ni), M3Al2B2 (M = Sc, T, Zr, Hf, Cr, Mn, Tc, Fe, Ru, Ni), M3AlB4 (M = Sc, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Fe), and M4AlB6 (M = Sc, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo). By comparing the formation energies of these MAB phases with those of their available competing binary M-B and M-Al, and ternary M-Al-B phases, we find that some of the Sc-, Ti-, V-, Cr-, Mo-, W-, Mn-, Tc-, and Fe-based MAB phases could be favorably synthesized under appropriate experimental conditions. In addition, by examining the strengths of various bonds in MAB phases via crystal orbital Hamilton population and spring constant calculations, we find that the B-B and then M-B bonds are stiffer than the M-Al and Al-B bonds. The different strengths between these bonds imply the etching possibility of Al atoms from MAB phases, consequently forming various 2D MB, M2B3, and M3B4 MBenes. Furthermore, we employ the nudged elastic band method to investigate the possibility of the structural phase transformation of the 2D MB MBenes into graphene-like boron sheets sandwiched between transition metals and find that the energy barrier of the transformation is less than 0.4 eV per atom.

The chemical synthesis of glycosyl inositol phospholipids from Entamoeba histolytica is reported. The key feature of this synthesis is a regioselective phosphorylation reaction that occurs through desymmetrization of a myo-inositol derivative with phosphoroselenoyl chloride. A new protecting-group strategy was developed that utilizes allyl and alloc groups to synthesize complex glycolipids bearing unsaturated lipids. These developments provided an efficient synthetic route for various complex inositol phospholipids and their analogues. Furthermore, the binding affinity of the synthetic inositol phospholipids with mouse CD1d molecules has been evaluated, as well as the immunostimulatory activity., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)