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In this study, we synthesized four bifunctional compounds containing two alkoxy groups, at which reactive thiol groups were introduced. Among these compounds, a compound with four and five methylene units in each alkyl chain did not exhibit a liquid crystalline phase. The other three compounds exhibit one or two liquid crystalline phases, and the number of liquid crystalline phases depends on the number of methylene units in their alkyl chains. These liquid crystalline compounds were oriented in one direction using a rubbed alignment film, and the oriented compounds were transferred onto a gold substrate. Using these gold substrates as working electrodes, cyclic voltammetry (CV) was performed with potassium ferricyanide as the redox probe. As the deposition time increased, the current intensities of a pair of redox waves gradually decreased. This trend suggests that with longer deposition times, a larger amount of the liquid crystalline compound was transferred to the gold substrate surface. These findings shed light on the relationship among the structures of bifunctional compounds, their liquid crystalline behavior, and their alignment properties on gold substrates, thereby offering valuable insights for potential applications in nanotechnology and materials science. [ABSTRACT FROM AUTHOR]

Nitroxyl radicals, characterized by unique redox properties, have been investigated for their potential influence on the photovoltaic conversion properties of dye-sensitized solar cells (DSSCs). In this study, we investigated the influence of nitroxyl radicals as donor sites in DSSCs. We observed that the redox activity of nitroxyl radicals significantly enhanced the photovoltaic conversion efficiency of DSSCs; this finding can offer new insights into the application of these radicals in solar energy conversion. Furthermore, we found that increasing the proportion of nitroxyl radicals improved the DSSC performance. Through a combination of experimental and analytical approaches, we elucidated the mechanism underlying this enhancement and highlighted the potential for more efficient DSSCs using nitroxyl radicals as key components. These findings provide new avenues for developing advanced DSSCs with improved performances and sustainability. [ABSTRACT FROM AUTHOR]

Background: The purpose of this study was to evaluate the association between endotheliopathy represented by high levels of circulating syndecan-1 (SDC-1) and coagulofibrinolytic responses due to trauma, which can lead to disseminated intravascular coagulation (DIC). Methods: We retrospectively evaluated 48 eligible trauma patients immediately admitted to our hospital and assessed SDC-1 and coagulofibrinolytic parameters for 7 days after admission. We compared the longitudinal changes of coagulofibrinolytic parameters and SDC-1 levels between two groups (high and low SDC-1) according to median SDC-1 value on admission. Results: The median circulating SDC-1 level was 99.6 (61.1–214.3) ng/mL on admission, and levels remained high until 7 days after admission. Coagulofibrinolytic responses assessed by biomarkers immediately after trauma were correlated with SDC-1 elevation (thrombin–antithrombin complex, TAT: r = 0.352, p = 0.001; antithrombin, AT: r = −0.301, p < 0.001; plasmin-α2-plasmin inhibitor complex, PIC: r = 0.503, p = 0.035; tissue plasminogen activator, tPA: r = 0.630, p < 0.001). Sustained SDC-1 elevation was associated with intense and prolonged coagulation activation, impairment of anticoagulation, and fibrinolytic activation followed by inhibition of fibrinolysis, which are the primary responses associated with development of DIC in the acute phase of trauma. Elevation of circulating SDC-1 level was also associated with consumption coagulopathy and the need for transfusion, which revealed a significant association between high SDC-1 levels and the development of DIC after trauma (area under the curve, AUC = 0.845, cut-off value = 130.38 ng/mL, p = 0.001). Conclusions: High circulating levels of syndecan-1 were associated with intense and prolonged coagulation activation, impairment of anticoagulation, fibrinolytic activation, and consumption coagulopathy after trauma. Endotheliopathy represented by SDC-1 elevation was associated with trauma induced coagulopathy, which can lead to the development of DIC. [ABSTRACT FROM AUTHOR]

Objectives: Laryngeal complications have been reported after endotracheal intubation and prone positioning in patients with critical coronavirus disease 2019 (COVID‐19), but their association is unclear. In this study, we investigated the rate of laryngeal complications in patients with COVID‐19 compared to an alternative condition (control group). Methods: We retrospectively analyzed the data of 40 patients who underwent endotracheal intubation for either COVID‐19 or an alternative condition (control group). Data on age, sex, body mass index (BMI), cardiovascular disease (CVD) risk factors, use of prone therapy, duration of endotracheal intubation, and duration from extubation/tracheostomy to laryngeal evaluation were collected from medical records. Results: There were no significant differences in BMI, frequency of CVD risk factors, duration of endotracheal intubation, or duration from extubation/tracheostomy to laryngeal evaluation between the two groups. In the COVID‐19 group, all patients adopted the prone position. In comparison, only one patient in the control group adopted the prone position. Significant differences were observed between the two groups regarding the incidence of vocal fold immobility and laryngeal granuloma. Conclusion: Laryngeal complications were more common in the COVID‐19 group than in the control group. Prone positioning may be a risk factor for these complications. Level of Evidence: 4. [ABSTRACT FROM AUTHOR]

We observed high and persistent spontaneous buildup of the surface potential (SP) upon vacuum deposition of tris(8-hydroxyquinolinato) aluminum(III) (Alq[sub 3]) on an Au substrate under dark conditions. SP determined by the Kelvin probe method reached 28 V at a thickness of 560 nm and the surface of the Alq[sub 3] film was positively charged. We propose a model in which preferential orientation of the dipole moments of Alq[sub 3] molecules is the origin of this buildup of the SP. The intensity of second-harmonic generation was also dramatically increased by the deposition of Alq[sub 3] under dark conditions, which supports the notion of a buildup of dipole layers. This giant surface potential was almost completely removed by irradiation of Alq[sub 3] molecules with visible light, and irradiation during deposition also prevented the buildup of SP. [ABSTRACT FROM AUTHOR]

The time resolved photoluminescence (TRPL) and the time resolved photocurrent (TRPC) are simultaneously measured for undoped (Al[sub 0.7]Ga[sub 0.3])[sub 0.5]In[sub 0.5]P/Al[sub x]In[sub 1-x]P (x = 0.53 and 0.57) superlattices. The bias voltage is applied on the semitransparent Au electrode on the epitaxial layer. From the measurement of the sample with x = 0.53 (lattice matched to the GaAs substrate), most of the carriers are recombined by nonradiative processes under the bias voltage of +0.3 - -1.0 V. The increase of the electric field causes the increase of electron flow from the surface region of the SL and the decrease in PL intensity. From the bias voltage dependence of the TRPL and TRPC properties, the amount of the radiatively recombined carriers are found to be less than 1 × 10[sup 9] when 1.4 × 10[sup 11] photons are incident on the sample. The surface electric field of the sample without the electrode is estimated to be less than 3 × 10[sup 3] V/cm during the PL measurement. For the sample with x = 0.57, the energy states originating from the crystal defects act as the carrier traps under a low-electric field and the levels which contribute to the tunneling of electrons through the potential barriers under a high-electric field. [ABSTRACT FROM AUTHOR]

Temporal developments of the photoluminescence (PL) intensity at temperatures of 7, 100, and 294 K are analyzed using the rate equations including the exciton dissociation and association terms for an Al[sub 0.53]In[sub 0.47]P/Ga[sub 0.52]In[sub 0.48]P/Al[sub 0.53]In[sub 0.47]P-quantum well structure. At 7 K, the nonexponential time dependence of the PL intensity is caused by the exciton dissociation process. At 7 and 100 K, PL intensity is dominated by the exciton recombination even if the exciton density is smaller than the dissociated carrier density. The thermally excited background carriers affect the recombination processes at 100 and 294 K. At 294 K, the rise part of the PL intensity is dominated by the exciton recombination, though the dissociated carrier density dominates. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]