Asymmetric Dimers of Chiral Azobenzene Dopants Exhibiting Unusual Helical Twisting Power upon Photoswitching in Cholesteric Liquid Crystals

In this study, we synthesized asymmetric dimeric chiral molecules as photon-mode chiral switches for reversible tuning of self-assembled helical superstructures. The chiral switches bearing two mesogen unitscholesterol and azobenzene moieties connected through flexible alkylenedioxy bridgeswere doped into nematic liquid crystals, resulting in a chiral nematic (cholesteric) phase. Under irradiation with UV light, photoisomerization of the azobenzene units led to unprecedented switching of the cholesteric pitch and helical twisting power (HTP, β), with a higher HTP found in the cis-rich state (bent-form) than in the trans-state (rod-form). We attribute this behavior to the elongated cybotactic smectic clusters disrupting the helical orientation of the molecules in the cholesteric liquid crystals; their reversible decay and reassembly was evidenced upon sequential irradiation with UV and visible light, respectively. In addition to the photoisomerization of the azobenzene units, the odd/even parity of the alkylenedioxy linkers of the dimeric dopants also had a dramatic effect on the transitions of the cybotactic smectic domains. On the basis of the large rotational reorganization of the cholesteric helix and HTP switching (Δβ/β_ini of up to 50%), we could control the macroscopic rotational motion of microsized glass rods upon irradiating the surface of a cholesteric liquid crystal film featuring a polygonal fingerprint texture using UV and visible light

Adherence to lifestyle recommendations among hypertensive subjects by awareness of hypertensive status.

<p>Engage in physical activity: >30 min of walking or moderate physical activity ≥5 days a week or ≥20 min of vigorous physical activity ≥3 days a week; moderation of alcohol intake: ≤2 drinks/day in males and ≤1 in females.</p><p>*Adherence adjusted for sex and age via survey regression analysis;</p><p>**β: mean difference adjusted for sex, age, residential area, educational level, income, and house ownership, history of diabetes mellitus, family histories of hypertension and stroke/ischemic heart disease, and duration of hypertension compared with those who were not aware of their hypertension status.</p><p>Adherence to lifestyle recommendations among hypertensive subjects by awareness of hypertensive status.</p

Representative Ca²⁺ oscillatory patterns in Sr²⁺-induced MII oocytes.

<p>Changes in the fluorescence of a Ca²⁺ indicator dye in mouse oocytes followed by incubation in Sr²⁺-containing medium revealed the almost normal pattern of Ca²⁺ oscillations in the control (<b>A</b>) and buffer-injected sham control (<b>B</b>) MII oocytes. However, <i>Gas6</i>-silence MII oocytes (<b>C</b>) exhibited both normal and abnormal patterns of Ca²⁺ oscillations. N, normal Ca²⁺ oscillatory pattern; Ab, abnormal Ca²⁺ oscillatory pattern.</p

<i>Gas6</i> RNAi impaired reactivation of MPF after emission of the first polar body.

<p>(<b>A</b>) To assess the activities of MPF and MAPK after <i>Gas6</i> RNAi, phosphorylation of the substrates histone H1 and MBP, reflecting the kinase activities of MPF and MAPK, respectively, was determined. Each lane contained one MII stage oocyte. Control, uninjected oocytes; Buffer, buffer-injected for sham control oocytes; <i>Gas6</i> RNAi, <i>Gas6</i> dsRNA-injected oocytes. (<b>B</b>) Dual kinase activity analysis to determine the phosphorylation levels of the substrates histone H1 and MBP was performed every 2 hours after <i>Gas6</i> RNAi injection. C, uninjected control oocytes; R, <i>Gas6</i>-depleted oocytes. (<b>C</b>) The amount of phosphorylated histone H1 was calculated, and relative amounts were presented in line graphs. Asterisks represent statistical significance at <i>p<</i>0.05. Intact line with open circles, Control, uninjected oocytes; Dotted line with closed circles, <i>Gas6</i> RNAi, <i>Gas6</i>-silenced oocytes. (<b>D</b>) Western blot analysis of cyclin B1, p34^cdc2, and p34^cdc2 p-Tyr15 in MII oocytes after <i>Gas6</i> RNAi treatment. Depletion of GAS6 protein after <i>Gas6</i> RNAi treatment affected MPF activity. Protein lysates of 250 MII oocytes were loaded per lane. α-Tubulin was used as a loading control. Control, uninjected control MII oocytes; <i>Gas6</i> RNAi, <i>Gas6</i>-silenced MII oocytes.</p

Development after parthenogenetic activation by Sr²⁺ stimulation.

a, b, c, d<p>Different letters indicate significant difference at <i>p<</i>0.05.</p

<i>Gas6</i> is not required for spindle and chromosomal dynamics in meiotic cell cycle.

<p>(<b>A</b>) Microphotographs in the left panel (1, 4, 7) show the oocytes under bright field, whereas microphotographs in the middle panel (2, 5, 8) show the noninvasive analysis of spindle structure in same oocytes using Polscope. Microphotographs in the right panel (3, 6, 9) show the results of aceto-orcein staining of chromosomes in MII oocytes. (<b>B</b>) Immunofluorescence staining for spindle and chromosome morphology in control and <i>Gas6</i> dsRNA-injected oocytes matured in vitro. MII oocytes were fixed in 4% paraformaldehyde, stained with α-tubulin antibody (Green), and counterstained with propidium iodide (Red) for DNA staining. Scale bars indicate 25 µm.</p

Emissions of Nanoparticles and Gaseous Material from 3D Printer Operation

This study evaluated the emissions characteristics of hazardous material during fused deposition modeling type 3D printing. Particulate and gaseous materials were measured before, during, and after 3D printing in an exposure chamber. One ABS and two PLA (PLA1 and PLA2) cartridges were tested three times. For online monitoring, a scanning mobility particle sizer, light scattering instrument, and total volatile organic compound (TVOC) monitor were employed and a polycarbonate filter and various adsorbent tubes were used for offline sampling. The particle concentration of 3D printing using ABS material was 33–38 times higher than when PLA materials were used. Most particles were nanosize (<100 nm) during ABS (96%) and PLA1 (98%) use, but only 12% were nanosize for PLA2. The emissions rates were 1.61 × 10¹⁰ ea/min and 1.67 × 10¹¹ ea/g cartridge with the ABS cartridge and 4.27–4.89 × 10⁸ ea/min and 3.77–3.91 × 10⁹ ea/g cartridge with the PLA cartridge. TVOCs were also emitted when the ABS was used (GM; 155 ppb, GSD; 3.4), but not when the PLA cartridges were used. Our results suggest that more research and sophisticated control methods, including the use of less harmful materials, blocking emitted containments, and using filters or adsorbents, should be implemented

In vitro maturation of mouse oocytes after injection of <i>Gas6</i> dsRNA into GV oocytes.

a, b, c<p>Different letters indicate significant difference at <i>p<</i>0.05.</p

Sperm penetration, but not pronuclear formation, occurred in <i>Gas6</i>-silenced MII oocytes.

<p>(<b>A</b>) After in vitro fertilization, eggs were fixed in 4% paraformaldehyde and stained with propidium iodide (red) to confirm the sperm DNA. Control eggs had both maternal and paternal PN formation through chromatin remodeling. On the contrary, <i>Gas6</i>-silenced eggs exhibited sperm penetration but not fully decondensed paternal chromatin in the cytoplasm. PN formation was not observed. White dot circles indicate PN formation, and white arrows indicate not fully decondensed paternal chromatin before PN formation. Control, uninjected eggs; Buffer, buffer-injected for sham control eggs; <i>Gas6</i> RNAi, <i>Gas6-</i>silenced eggs. (<b>B</b>) Percentage of oocytes with PN formation after in vitro fertilization. The black columns indicate the percentage of oocytes with PN formation, and the white columns indicate the percentage of oocytes without PN formation.</p

Roscovitine and colcemid treatment to regulate the MPF activity in MII oocytes.

<p>(<b>A</b>) Schematic outline of the experimental procedure. Roscovitine, a specific inhibitor of p34^cdc2-cyclin B1 kinase, was used to inactivate MPF. Control oocytes were cultured in M16 medium for 10 hours, and then transferred in M16 medium containing roscovitine, when first polar body was emitted. Colcemid, a drug for preventing the degradation of Cyclin B, was used to maintain MPF activity. Control and <i>Gas6</i>-dsRNA injected oocytes were cultured in M16 medium for 10 hours until the first polar body extrusion followed by culture in M16 medium containing colcemid for 6 hours. (<b>B</b>) Dual kinase activity analysis to determine the activation levels of the MPF and MAPK was performed. Roscovitine-treated oocytes suppressed activity of MPF and colcemid-treated oocytes maintained activity of MPF.</p