Synthesis and Characterization of Two-Dimensional Conjugated Polymers Incorporating Electron-Deficient Moieties for Application in Organic Photovoltaics

A series of novel p-type conjugated copolymers, PTTVBDT, PTTVBDT-TPD, and PTTVBDT-DPP, cooperating benzo[1,2-b:4,5-b′]dithiophene (BDT) and terthiophene-vinylene (TTV) units with/without thieno[3,4-c]pyrrole-4,6-dione (TPD) or pyrrolo[3,4-c]pyrrole-1,4-dione (DPP) via Stille polymerization were synthesized and characterized. Copolymer PTTVBDT shows a low-lying HOMO energy level and ordered molecular-packing behavior. Furthermore, two terpolymers, PTTVBDT-TPD and PTTVBDT-DPP, display stronger absorption ability, alower-lying HOMO energy level, and preferred molecular orientation, due to the replacement TTV-monomer units with electron-deficient groups. Furthermore, bulk-heterojunction organic solar cells were fabricated using blends of the PTTVBDT-TPD, and PC_(61)BM gave the best power conversion efficiency of 5.01% under the illumination of AM 1.5G, 100 mW·cm^(−2); the short circuit current (J_(sc)) was 11.65 mA·cm^(−2) which displayed a 43.8% improvement in comparison with the PTTVBDT/PC_(61)BM device. These results demonstrate a valid strategy combining the two-dimensional molecular structure with random copolymerization strikes promising conjugated polymers to achieve highly efficient organic photovoltaics

Modified structure of two-dimensional polythiophene derivatives by incorporating electron-deficient units into terthiophene-vinylene conjugated side chains and the polymer backbone: synthesis, optoelectronic and self-assembly properties, and photovoltaic application

Molecular engineering on the conjugated side chains of two-dimensional (2D) conjugated polymers was conducted and its effect on the optical, electronic, self-assembly and photovoltaic properties was investigated. A new monomer, M2, was prepared by capping (E)-3′-(2-(2,5-dibromothiophen-3-yl)vinyl)-4,4′′-bis(2-ethylhexyl)-2,2′:5′,2′′-terthiophene, M1, with two heptanoyl groups, and then coupled with 5,5′-bis(trimethylstannyl)-2,2′-bithiophene via microwave-assisted Stille polymerization to produce a series of polythiophene derivatives with terthiophene-vinylene conjugated side chains, TTV–PTs. Copolymer P2 shows a down-shifted HOMO energy level, enhanced solubility, and red-shifted absorption, as compared with P1; however, the bulky side chains significantly disrupt the coplanarity of thiophene rings in the polymer backbone and the ability to self-assemble into an ordered structure. The GIXRD measurements reveal that the original crystallinity of P1 can be recovered by simply inserting a few 2,1,3-benzothiadiazole units into the polythiophene main chain in P2 through a random copolymerization route to yield a terpolymer, P3, which possesses excellent crystallinity, thereby causing a three-fold increment in hole mobility. Furthermore, the P1/PC_(61)BM, P2/PC_(61)BM, and P3/PC61BM solar devices exhibit power conversion efficiencies of 3.89%, 1.52%, and 4.17%, respectively, under AM1.5G illumination with an intensity of 100 mW cm^(−2)

Modified structure of two-dimensional polythiophene derivatives by incorporating electron-deficient units into terthiophene-vinylene conjugated side chains and the polymer backbone: synthesis, optoelectronic and self-assembly properties, and photovoltaic application

Molecular engineering on the conjugated side chains of two-dimensional (2D) conjugated polymers was conducted and its effect on the optical, electronic, self-assembly and photovoltaic properties was investigated. A new monomer, M2, was prepared by capping (E)-3′-(2-(2,5-dibromothiophen-3-yl)vinyl)-4,4′′-bis(2-ethylhexyl)-2,2′:5′,2′′-terthiophene, M1, with two heptanoyl groups, and then coupled with 5,5′-bis(trimethylstannyl)-2,2′-bithiophene via microwave-assisted Stille polymerization to produce a series of polythiophene derivatives with terthiophene-vinylene conjugated side chains, TTV–PTs. Copolymer P2 shows a down-shifted HOMO energy level, enhanced solubility, and red-shifted absorption, as compared with P1; however, the bulky side chains significantly disrupt the coplanarity of thiophene rings in the polymer backbone and the ability to self-assemble into an ordered structure. The GIXRD measurements reveal that the original crystallinity of P1 can be recovered by simply inserting a few 2,1,3-benzothiadiazole units into the polythiophene main chain in P2 through a random copolymerization route to yield a terpolymer, P3, which possesses excellent crystallinity, thereby causing a three-fold increment in hole mobility. Furthermore, the P1/PC_(61)BM, P2/PC_(61)BM, and P3/PC61BM solar devices exhibit power conversion efficiencies of 3.89%, 1.52%, and 4.17%, respectively, under AM1.5G illumination with an intensity of 100 mW cm^(−2)

Synthesis and Characterization of Two-Dimensional Conjugated Polymers Incorporating Electron-Deficient Moieties for Application in Organic Photovoltaics

A series of novel p-type conjugated copolymers, PTTVBDT, PTTVBDT-TPD, and PTTVBDT-DPP, cooperating benzo[1,2-b:4,5-b′]dithiophene (BDT) and terthiophene-vinylene (TTV) units with/without thieno[3,4-c]pyrrole-4,6-dione (TPD) or pyrrolo[3,4-c]pyrrole-1,4-dione (DPP) via Stille polymerization were synthesized and characterized. Copolymer PTTVBDT shows a low-lying HOMO energy level and ordered molecular-packing behavior. Furthermore, two terpolymers, PTTVBDT-TPD and PTTVBDT-DPP, display stronger absorption ability, alower-lying HOMO energy level, and preferred molecular orientation, due to the replacement TTV-monomer units with electron-deficient groups. Furthermore, bulk-heterojunction organic solar cells were fabricated using blends of the PTTVBDT-TPD, and PC_(61)BM gave the best power conversion efficiency of 5.01% under the illumination of AM 1.5G, 100 mW·cm^(−2); the short circuit current (J_(sc)) was 11.65 mA·cm^(−2) which displayed a 43.8% improvement in comparison with the PTTVBDT/PC_(61)BM device. These results demonstrate a valid strategy combining the two-dimensional molecular structure with random copolymerization strikes promising conjugated polymers to achieve highly efficient organic photovoltaics

AV-SUPERB: A Multi-Task Evaluation Benchmark for Audio-Visual Representation Models

Audio-visual representation learning aims to develop systems with human-like perception by utilizing correlation between auditory and visual information. However, current models often focus on a limited set of tasks, and generalization abilities of learned representations are unclear. To this end, we propose the AV-SUPERB benchmark that enables general-purpose evaluation of unimodal audio/visual and bimodal fusion representations on 7 datasets covering 5 audio-visual tasks in speech and audio processing. We evaluate 5 recent self-supervised models and show that none of these models generalize to all tasks, emphasizing the need for future study on improving universal model performance. In addition, we show that representations may be improved with intermediate-task fine-tuning and audio event classification with AudioSet serves as a strong intermediate task. We release our benchmark with evaluation code and a model submission platform to encourage further research in audio-visual learning.Comment: Submitted to ICASSP 2024; Evaluation Code: https://github.com/roger-tseng/av-superb Submission Platform: https://av.superbbenchmark.or

Origin, Transport, and Vertical Distribution of Atmospheric Polluntants over the Northern Sourth China Sea During the 7-SEAS-Dongsha Experiment

During the spring of 2010, comprehensive in situ measurements were made for the first time on a small atoll (Dongsha Island) in the northern South China Sea (SCS), a key region of the 7-SEAS (the Seven South East Asian Studies) program. This paper focuses on characterizing the source origins, transport processes, and vertical distributions of the Asian continental outflows over the region, using measurements including mass concentration, optical properties, hygroscopicity, and vertical distribution of the aerosol particles, as well as the trace gas composition. Cluster analysis of backward trajectories classified 52% of the air masses arriving at ground level of Dongsha Island as having a continental origin, mainly from northern China to the northern SCS, passing the coastal area and being confined in the marine boundary layer (0-0.5 km). Compared to aerosols of oceanic origin, the fine mode continental aerosols have a higher concentration, extinction coefficient, and single-scattering albedo at 550 nm (i.e., 19 vs. 14 microg per cubic meter in PM(sub 2.5); 77 vs. 59 M per meter in beta(sub e); and 0.94 vs. 0.90 in omega, respectively). These aerosols have a higher hygroscopicity (f at 85% RH = 2.1) than those in the upwind inland regions, suggesting that the aerosols transported to the northern SCS were modified by the marine environment. In addition to the near-surface aerosol transport, a significant upper-layer (3-4 km) transport of biomass-burning aerosols was observed. Our results suggest that emissions from both China and Southeast Asia could have a significant impact on the aerosol loading and other aerosol properties over the SCS. Furthermore, the complex vertical distribution of aerosols-coinciding-with-clouds has implications for remote-sensing observations and aerosol-cloud-radiation interactions

An Overview of Regional Experiments on Biomass Burning Aerosols and Related Pollutants in Southeast Asia: From BASE-ASIA and the Dongsha Experiment to 7-SEAS

By modulating the Earth-atmosphere energy, hydrological and biogeochemical cycles, and affecting regional-to-global weather and climate, biomass burning is recognized as one of the major factors affecting the global carbon cycle. However, few comprehensive and wide-ranging experiments have been conducted to characterize biomass-burning pollutants in Southeast Asia (SEA) or assess their regional impact on meteorology, the hydrological cycle, the radiative budget, or climate change. Recently, BASEASIA (Biomass-burning Aerosols in South-East Asia: Smoke Impact Assessment) and the 7-SEAS (7- South-East Asian Studies) Dongsha Experiment were conducted during the spring seasons of 2006 and 2010 in northern SEA, respectively, to characterize the chemical, physical, and radiative properties of biomass-burning emissions near the source regions, and assess their effects. This paper provides an overview of results from these two campaigns and related studies collected in this special issue, entitled Observation, modeling and impact studies of biomass burning and pollution in the SE Asian Environment. This volume includes 28 papers, which provide a synopsis of the experiments, regional weatherclimate, chemical characterization of biomass-burning aerosols and related pollutants in source and sink regions, the spatial distribution of air toxics (atmospheric mercury and dioxins) in source and remote areas, a characterization of aerosol physical, optical, and radiative properties, as well as modeling and impact studies. These studies, taken together, provide the first relatively complete dataset of aerosol chemistry and physical observations conducted in the sourcesink region in the northern SEA, with particular emphasis on the marine boundary layer and lower free troposphere (LFT). The data, analysis and modeling included in these papers advance our present knowledge of source characterization of biomass-burning pollutants near the source regions as well as the physical and chemical processes along transport pathways. In addition, we raise key questions to be addressed by a coming deployment during springtime 2013 in northern SEA, named 7-SEASBASELInE (Biomass-burning Aerosols Stratocumulus Environment: Lifecycles and Interactions Experiment). This campaign will include a synergistic approach for further exploring many key atmospheric processes (e.g., complex aerosol-cloud interactions) and impacts of biomass burning on the surface-atmosphere energy budgets during the lifecycles of biomass burning emissions

Comparison of single-incision mini-slings (Ajust) and standard transobturator midurethral slings (Align) in the management of female stress urinary incontinence: A 1-year follow-up

AbstractObjectiveTo investigate the effectiveness and safety of a new single-incision mini-sling (SIMS)—Ajust—compared with the standard transobturator midurethral sling (SMUS)—Align—for the treatment of female stress urinary incontinence (SUI).Materials and MethodsA retrospective cohort study was conducted between January 1, 2010 and August 31, 2012. Women with SUI who underwent either SMUS-Align or SIMS-Ajust were recruited. The primary outcomes included operation time, estimated operative blood loss, postoperative pain, and complications. The secondary outcomes included subjective and objective success, defined as an International Consultation on Incontinence Questionnaire (ICIQ) score of 0 or improvement as felt by the patient and a long-term complication, such as dyspareunia and mesh erosion after 6 months and 12 months of follow-up.ResultsA total of 136 patients were enrolled, including 76 receiving SMUS-Align and 60 receiving SIMS-Ajust. Baseline characteristics of the patients in both groups were similar, without a statistically significant difference. Primary outcomes between both groups were similar, except that women treated with SIMS-Ajust had statistically significantly shorter operation time (p = 0.003), less intent to treat (p < 0.05), and earlier postoperative discharge (p = 0.001) than women treated with SMUS-Align. Secondary outcomes were similar without a significant difference between the two groups (93% vs. 88% success rate in each group).ConclusionOur results showed that SIMS-Ajust was not inferior to SMUS-Align with respect to success rate, and might have a slight advantage in early discharge. A long-term follow-up or prospective study is needed to confirm the above findings

Glyoxalase-I Is a Novel Prognosis Factor Associated with Gastric Cancer Progression

Glyoxalase I (GLO1), a methylglyoxal detoxification enzyme, is implicated in the progression of human malignancies. The role of GLO1 in gastric cancer development or progression is currently unclear. The expression of GLO1 was determined in primary gastric cancer specimens using quantitative polymerase chain reaction, immunohistochemistry (IHC), and western blotting analyses. GLO1 expression was higher in gastric cancer tissues, compared with that in adjacent noncancerous tissues. Elevated expression of GLO1 was significantly associated with gastric wall invasion, lymph node metastasis, and pathological stage, suggesting a novel role of GLO1 in gastric cancer development and progression. The 5-year survival rate of the lower GLO1 expression groups was significantly greater than that of the higher expression groups (log rank P = 0.0373) in IHC experiments. Over-expression of GLO1 in gastric cancer cell lines increases cell proliferation, migration and invasiveness. Conversely, down-regulation of GLO1 with shRNA led to a marked reduction in the migration and invasion abilities. Our data strongly suggest that high expression of GLO1 in gastric cancer enhances the metastasis ability of tumor cells in vitro and in vivo, and support its efficacy as a potential marker for the detection and prognosis of gastric cancer