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Two novel phenanthroimidazole derivatives were synthesized for efficient three-photon excited fluorescence and absorption. By introducing spirobi [9H-fluorene] to replace fluorene, the three-photon-excited fluorescence and cross-section are significantly enhanced to 3.56 ± 0.15 × 10 −78 cm 6 s 2 photon −2 , which is among the highest reported values for organic molecules. Our results supply a useful method to develop novel materials for applications of three-photon excited fluorescence and absorption. [ABSTRACT FROM AUTHOR]

We present a frequency-domain technique for identifying multivariable feedback and feedforward subsystems that are interconnected with a known subsystem. This subsystem identification algorithm uses closed-loop input–output data, but no other system signals are assumed to be measured. In particular, neither the feedback signal nor the outputs of the unknown subsystems are assumed to be measured. We use a candidate-pool approach to identify the feedback and feedforward transfer function matrices, while guaranteeing asymptotic stability of the identified closed-loop transfer function matrix. The main analytic result shows that if the data noise is sufficiently small and the candidate pool is sufficiently dense, then the parameters of the identified feedback and feedforward transfer function matrices are arbitrarily close to the true parameters. [ABSTRACT FROM AUTHOR]

Two novel donor–acceptor conjugated polymers with 5 H -dithieno[3,2- b :2',3'- d ]pyran as a strong electron-donating unit and diketopyrrolopyrrole as electron accepting units were synthesized. The photophysical and electrochemical properties were investigated and compared. With the same donor unit, 3,6-di(thien-2-yl)pyrrolopyrroledione-based polymer showed an almost linear spatial structure, while 3,6-di(furan-2-yl)pyrrolopyrroledione-based polymer exhibited a V-shaped structure. The power conversion efficiency of solar cells based on 3,6-di(thien-2-yl)pyrrolopyrroledione-based polymer, with a high carrier mobility benefiting from almost linear backbone of 3,6-di(thien-2-yl)pyrrolopyrroledione-based polymer, was much higher than that of photovoltaic cells based on 3,6-di(furan-2-yl)pyrrolopyrroledione-based polymer. This work demonstrated a good example for enhancing efficiency of diketopyrrolopyrrole-based solar cells by adjusting the spatial structure. [ABSTRACT FROM AUTHOR]

Abstract: The simultaneous utilization of all charge-transfer excitons and local excitons is the pathway to obtain the high efficiency fluorescent organic light-emitting diodes (FOLEDs). Here, a twisted intramolecular charge transfer state (TICT-state), a planar intramolecular charge transfer state (ICT-state), and a locally excited state (LE-state) are demonstrated to enhance the occurrence of singlet excitons in the fluorescent emitters, which are based on benzimidazole and triphenylamine donor–acceptor derivatives. The synthesis, photophysics and electroluminescent (EL) performance are studied systematically. The fluorescence emitters (TPABBBI and TPABBI) with the special TICT and ICT characteristics realize the electron–hole (e–h) recombination via intramolecular conversion from charge-transfer excitons to radiative singlet exciton. The devices based on them show high efficiency (5.1 cd/A, 5.77 lm/W, 5.66% of EQEm for TPABBBI and 3.56 cd/A, 3.11 lm/W, 4.23% for TPABBI), low efficiency roll-off at high luminance and stable blue emission. [Copyright &y& Elsevier]

Watertight duraplasty is essential for surgical management of traumatic anterior skull base (ASB) dural defect but challenging in the deep and narrow operative corridor. Here, the authors report a trans-defect underlay watertight duraplasty (TDUWD) technique for traumatic ASB dural defect. TDUWD was performed by inserting a free pericranium graft under the dural defect. The diameter of the pericranium graft was larger than the dural defect. The pericranium graft was sutured to the dural defect watertightly in an "inside-to-outside" direction, with the needle not penetrating the inner layer of pericranium graft. The pedicled pericranium flap was used as a second layer of reconstruction. The characteristics, complications, and outcomes of patients who received TDUWD are reported. A total of 29 patients received TDUWD. Immediate postoperative cessation of cerebrospinal fluid (CSF) leak occurred in 28 patients. One patient recovered after lumber drainage. No patient needed a second operation or reported delayed recurrence of CSF leak. No complication related to the surgical technique was observed. Use of TDUWD for traumatic ASB dural defect results in an immediate, 1-stage, and definitive correction of CSF leak and seems to be simple, safe, and reliable for large and deeply located dural defects. [ABSTRACT FROM AUTHOR]

A couple of phenanthrene isomers were designed and synthesized by introducing strong D–π–A structure strategy to manage effectively their intramolecular charge transfer processes for violet-blue emitters. Their physical properties, including UV–vis, photoluminescence, thermal and electrochemistry, were systematically studied. The results were found to be good candidates as emitters for organic light emitting diodes (OLEDs). The devices based on them exhibit deep-blue light emissions with CIE coordinates of (0.15, 0.15) for p-PATPA and violet-blue (0.16, 0.05) for m-PATPA at 100 cd/m 2 , respectively. The violet-blue device shows good performance with external quantum efficiency (EQE), current efficiency (CE), and power efficiency (PE) of 2.39%, 0.78 cd/A, and 0.72 lm/W, respectively. Furthermore, at the high luminescence, the device still indicated good performance with relative low efficiency roll-off. Our results here successfully provide an efficient design strategy with strong donor and acceptor for violet-blue emitters. [ABSTRACT FROM AUTHOR]

Abstract: Two novel benzimidazole-attached spiro[benzofluorene] derivatives, 2,2′-(spiro[benzo[c]fluorine-7,9′-fluorene]-5,9-diylbis(4,1-phenylene))bis(1-phenyl-1H-benzo[d]imidazole) and 2,2′-(spiro[benzo-[de]anthracene-7,9′-fluorene]-2′,3-diylbis(4,1-phenylene))bis(1-phenyl-1H-benzo[d]imidazole), were prepared by a Suzuki coupling reaction. Their photophysical and photochemical properties were studied systemically. The fluorescent organic light-emitting diodes were fabricated by using them as the emitters, all of them showed strong blue emission. Interestingly, from the benzoanthracene derived compound a high color purity was found with Commission de L'Eclairage 1931 chromaticity coordinates of (0.15, 0.10) and an efficiency of 1.96 cd/A. To the best of our knowledge, this is the first time to obtain a deep-blue emission with spiro[benzofluorene] derivative in a nondoped device. [Copyright &y& Elsevier]

Background The safety and efficacy of craniotomy, endoscopic surgery, and stereotactic aspiration for surgical evacuation of spontaneous supratentorial lobar intracerebral hemorrhage (ICH) is yet uncertain. The present study analyzed the clinical and radiographic data from 99 patients with spontaneous supratentorial lobar ICH, retrospectively, to address this issue. Methods Patients who underwent craniotomy, endoscopy surgery, or stereotactic aspiration were assigned to the craniotomy group ( n = 31), endoscopy surgery group ( n = 32), or stereotactic aspiration group ( n = 36), respectively. The characteristics of all the enrolled patients at the time of admission were assimilated. Also, the therapeutic effects of the three surgical procedures were evaluated based on short-term outcomes within 30 days and long-term outcomes at 6 months after the ictus. Results The results showed that stereotactic aspiration and endoscopic surgery were associated with a superior clinical therapeutic effect in both short-term and long-term outcomes than craniotomy for the treatment of spontaneous supratentorial lobar ICH. Notably, severely affected patients with hematoma volume > 60 mL or Glasgow Coma Scale score 4–8 may benefit more from endoscopic surgery than the two other surgical procedures. Conclusions The current findings demonstrate that both stereotactic aspiration and endoscopic surgery possess an apparent advantage over craniotomy for the evacuation of spontaneous supratentorial lobar ICH. The endoscopic surgery might be more safe and effective with higher evacuation rate, better functional neurological outcomes, and lower complication and mortality rates. [ABSTRACT FROM AUTHOR]

Ionic conductive hydrogel with multifunctional properties have shown promising application potential in various fields, including electronic skin, wearable devices and sensors. Herein, a highly stretchable (up to 2800% strain), tough, adhesive ionic conductive hydrogel are prepared using cationic nanocellulose (CCNC) to disperse/stabilize graphitic carbon nitride (g-C 3 N 4), forming CCNC-g-C 3 N 4 complexes and in situ radical polymerization process. The ionic interactions between CNCC and g-C 3 N 4 acted as sacrificial bonds enabled highly stretchability of the hydrogel. The hydrogel showed high sensitivity (gauge factor≈5.6, 0–1.6% strain), enabling the detection of human body motion, speech and exhalation. Furthermore, the hydrogel based self-powered device can charge 2.2 μF capacitor up to 15 V from human motion. This multifunctional hydrogel presents potential applications in self-powered wearable electronics. [Display omitted] • A highly stretchable hydrogel is developed based on nanocomposite incorporation. • Cationic nanocellulose (CNCC) is used to disperse/stabilize C 3 N 4. • The C 3 N 4 -CNCC endows electrostatic interaction and hydrogen bonding for PAM network. • The capabilities of hydrogel as motion and temperature detection are verified. • The hydrogel derived self-powered device can charge 47uF capacitor to 15 V. [ABSTRACT FROM AUTHOR]

Background Current surgical therapies for spontaneous intracerebellar hemorrhage (SCH) include suboccipital craniotomy (SC), stereotactic aspiration and thrombolysis (SAT), and endoscopic surgery (ES). Evidence comparing the therapeutic effects of these 3 methods is scarce. The safety and efficacy of SC, SAT, and ES for SCH are still uncertain. Methods 75 patients with SCH who received SC, SAT, or ES were reviewed retrospectively. Baseline parameters before the operation, evacuation rate, perihematoma edema, postoperative complications, and cumulative case fatalities were collected. Also, 12 months after ictus, the long-term functional outcomes in patients with regard to fourth ventricle compression and age were judged, respectively, by the modified Rankin Scale (mRS). Results The SAT was less effective in evacuating hematoma than were SC and ES. The perihematoma edema on postoperative day 7 and surgical complications were highest in the SC group. The functional outcome represented by mRS was better in the SAT group than in the SC and ES groups for patients with fourth ventricle compression grade 1. For patients with fourth ventricle compression grades 2 and 3, the ES group achieved the best functional outcome. Patients older than 60 years benefited less from SC than from ES and SAT. Conclusions SAT may be suitable for SCH patients with fourth ventricle compression grade 1, and ES may be suitable for SCH patients with fourth ventricle compression grades 2 and 3. Aged patients benefit less from SC than from SAT and ES. [ABSTRACT FROM AUTHOR]

Background Ultra-early surgical clot removal relieves mechanical compression on adjacent normal brain tissue and limits the toxic effects of a hematoma, which might improve the outcomes in patients with intracerebral hemorrhage (ICH); however, hematoma expansion frequently occurs within 20 hours after the ictus, and this limits the use of ultra-early surgery. Computed tomography angiography spot sign was recently validated as an important predictor of hematoma expansion in patients with ICH. Methods Fifty-nine patients with ICH and negative spot sign who received ultra-early stereotactic aspiration (<6 hours after ictus; n = 32 [Ultra-early group]) or routine stereotactic aspiration (≥6 hours after ictus; n = 27 [Routine group]) were included in retrospective analysis. Results The percentage of rebleeding was not significantly different between the 2 groups. Perihematoma edema 7 days after surgery in the Ultra-early group was significantly less frequent than that in the Routine group. For long-term outcomes, the proportion of patient fatalities and Glasgow Outcome Scale score were not significantly different between the 2 groups; however, for patients with severe symptoms, the rate of good neurological outcome in the Ultra-early group was higher than that in the Routine group. Conclusions Ultra-early stereotactic aspiration might decrease the volume of perihematoma edema and improve the functional outcomes to some extent, without increasing the recurrence of ICH and patient fatalities. Our findings suggest that using negative spot sign as an indicator for performing ultra-early stereotactic aspiration could be a safe and effective protocol for ICH patients. [ABSTRACT FROM AUTHOR]