Dopant-Free Pyrrolopyrrole-Based (PPr) Polymeric Hole-Transporting Materials for Efficient Tin-Based Perovskite Solar Cells with Stability Over 6000 h.

A new set of pyrrolopyrrole-based (PPr) polymers incorporated with thioalkylated/alkylated bithiophene (SBT/BT) is synthesized and explored as hole-transporting materials (HTMs) for Sn-based perovskite solar cells (TPSCs). Three bithiophenyl spacers bearing the thioalkylated hexyl (SBT-6), thioalkylated tetradecyl (SBT-14), and tetradecyl (BT-14) chains are utilized to examine the effect of the alkyl chain lengths. Among them, the TPSCs are fabricated using PPr-SBT-14 as HTMs through a two-step approach by attaining a power conversion efficiency (PCE) of 7.6% with a remarkable long-term stability beyond 6000 h, which has not been reported elsewhere for a non-PEDOT:PSS-based TPSC. The PPr-SBT-14 device is stable under light irradiation for 5 h in air (50% relative humidity) at the maximum power point (MPP). The highly planar structure, strong intramolecular S(alkyl)···S(thiophene) interactions, and extended π-conjugation of SBT enable the PPr-SBT-14 device to outperform the standard poly(3-hexylthiophene,-2,5-diyl (P3HT) and other devices. The longer thio-tetradecyl chain in SBT-14 restricts molecular rotation and strongly affects the molecular conformation, solubility, and film wettability over other polymers. Thus, the present study makes a promising dopant-free polymeric HTM model for the future design of highly efficient and stable TPSCs.

The effect of preperitoneal pelvic packing for hemodynamically unstable patients with pelvic fractures.

PURPOSE: Hemodynamically unstable patients with pelvic fractures still represent a challenge to trauma surgeons and have a very high mortality. This study was designed to explore the effect of the interventions of direct preperitoneal pelvic packing for the hemodynamically unstable pelvic fractures. METHODS: This retrospective study enrolled 67 cases of severe pelvic fractures with unstable hemodynamics from October 2011 to December 2019. All patients presented in our emergency center and received preperitoneal pelvic packing were included in this study. The indication was persistent systolic blood pressure ≤90 mmHg during initial resuscitation and after transfusion of two units of red blood cells. Patients with hemodynamic stability who need no preperitoneal pelvic packing to control bleeding were excluded. Their demographic characteristics, clinical features, laboratory results, therapeutic interventions, adverse events, and prognostic outcomes were collected from digital information system of electronic medical records. Statistics were described as mean ± standard deviation or medium and analyzed using pair sample t-test or Mann-Whitney U-test. RESULTS: The patients' average age was 41.6 years, ranging from 10 to 88 years. Among them, 45 cases were male (67.2%) and 22 cases were female (32.8%). Significant difference was found regarding the systolic blood pressure (mmHg) in the emergency department (78.4 ± 13.9) and after preperitoneal pelvic packing in the surgery intensive care unit (100.1 ± 17.6) (p < 0.05). Simultaneously, the arterial base deficit (mmol/L) were significantly lower in the surgery intensive care unit (median -6, interquartile range -8 to -2) than in the emergency department (median -10, interquartile range -14 to -8) (p < 0.05). After preperitoneal pelvic packing, 15 patients (22.4%) underwent pelvic angiography for persistent hypotension or suspected ongoing haemorrhage. The overall mortality rate was 29.5% (20 of 67). CONCLUSIONS: Preperitoneal pelvic packing, as a useful surgical technique, is less invasive and can be very efficient in early intra-pelvic bleed control.

Ferrate Oxidation of Phenolic Compounds in Iodine-Containing Water: Control of Iodinated Aromatic Products.

Highly toxic iodinated products would form in oxidation and disinfection of iodine-containing water. Variation of iodinated aromatic products in ferrate [Fe(VI)] oxidation of phenolic compounds (phenol, bisphenol A (BPA), and p-hydroxybenzoic acid (p-HBA)) in iodine-containing water was investigated. At pH 5.0, oxidation of phenolic compounds was inhibited by competitive reaction of ferrate with I-, and no formation of iodinated aromatic products was detected. Almost all I- was converted into nontoxic IO3-. At pH 7.0, 8.0, and 9.0, HOI formed in ferrate oxidation of I- and further reacted with phenols, with the formation of iodinated aromatic products. Mass spectrometry analysis showed that both kinds and contents of iodinated aromatic products were raised with the increase in solution pH and the content of I-, and these iodinated aromatic products were further oxidized by ferrate. Ferrate deprived iodine from iodinated aromatic products and transferred highly toxic organic iodine into nontoxic IO3-. An electron-donating substituent (alkyl) increased the reactivity of phenol with ferrate and HOI and facilitated ferrate oxidation of iodinated phenols. An electron-drawing substituent (carboxyl) decreased the reactivity of phenol with ferrate and HOI and hindered the further oxidation of iodinated aromatic products. A kinetic model about the variation of phenol, BPA, and p-HBA in reaction with ferrate in iodine-containing water was developed, and the oxidation profile of phenolic compounds could be satisfactorily predicted at various iodide concentrations.

Neurogenic locus notch homolog protein 4 and brain-derived neurotrophic factor variants combined effect on schizophrenia susceptibility.

OBJECTIVES: To investigate the relationships between single-nucleotide polymorphisms (SNPs) in NOTCH4 and brain-derived neurotrophic factor (BDNF) with schizophrenia among Han Chinese in Southern China. METHODS: Two NOTCH4 SNPs (rs520688 and rs415929) and two BDNF SNPs (rs2030324 and rs12273539) were examined in 464 schizophrenics and 464 healthy controls from Hunan province in South China, using the Sequenom MassARRAY® iPLEX System. RESULTS: In the study population, rs520688 and rs2030324 were significantly associated with schizophrenia. A decreased risk of schizophrenia was associated with the rs520688 GA genotype (p = 0.035), whereas an increased risk of schizophrenia was associated with the rs2030324 CC/CT genotype (p = 0.044). The genotype distributions of rs415929 in NOTCH4 and rs12273539 in BDNF did not differ significantly between the case and control groups. Although no allele-allele interactions were detected between rs520688 and rs2030324, recombination analysis revealed a combined effect of the two on the susceptibility to schizophrenia, with GA-TT decreasing and CT/CC-GG/GA increasing the risk of schizophrenia. CONCLUSION: In conclusion, rs520688 in NOTCH4 and rs2030324 in BDNF are significantly associated with schizophrenia among Han Chinese in Southern China. The two had a combined effect on the susceptibility to schizophrenia among Han Chinese in Southern China, but this may not be caused by an allele-allele interaction.

Polarization-dependent plasmonic coupling in dual-layer metallic structures at terahertz frequencies.

Dual-layer metallic wire-hole structures were fabricated and their terahertz transmission properties were measured. They exhibit polarization-dependent transmittance with large extinction ratios. Simulation and experimental results on structures with different wire-to-hole orientations provide strong evidence that the resonance peaks are caused by plasmonic coupling between the two metallic layers. A simplified LC-circuit model is proposed to explain the coupling mechanism and to estimate the peak frequencies. Our results suggest that specific electromagnetic response can be achieved by appropriate design of the geometrical patterns on the two metallic layers and a suitable polarization of the incident wave.

Plasmonic waveguiding in a hexagonally ordered metal wire array.

We propose the inclusion of a structured pattern of nanoscale metal wires in a silica fiber to form a symmetric plasmonic waveguide. The surface plasmon polariton modes within the waveguide are studied by varying the wire diameter and spacing. Simulation results show that hybridization of the single-wire mode and the gap plasmon mode can yield a hybrid mode with optimum propagation lengths comparable to those reported for other structures but with better light confinement. The fiber can be easily doped with a gain material to offset the loss so that the resultant waveguide will be useful for integration with electronic circuits at nanometer dimensions.