Discourse-based psychological intervention alleviates perioperative anxiety in patients with adolescent idiopathic scoliosis in China: a retrospective propensity score matching analysis.

PURPOSE: To evaluate the effectiveness of a discourse-based psychological intervention on perioperative anxiety, pain and life satisfaction of patients with AIS. METHODS: Between April 2018 and February 2021, 116 consecutive patients with AIS undergoing corrective surgery were enrolled in this study, including 51 with personalized psychological intervention (intervention group, IG) and 65 without (control group, CG). After propensity score matching (PSM), patient characteristics, perioperative scores of anxiety and life satisfaction, measured by values of Generalized Anxiety Disorder 7-item Scale (GAD-7) and Life Satisfaction Index Z scale (LSIZ), were recorded. Mixed linear models were used to estimate the influence of intervention group and time of measurement, as well as their interactions, in anxiety and life satisfaction. Data on post-surgical pain in both groups was also collected and analyzed. RESULTS: After PSM, a total of 90 patients (IG, n = 45; CG, n = 45) were enrolled in this study, and the 2 groups were comparable in patients' demographic and baseline characteristics. There were no pre-intervention between-group differences in the degree of anxiety (IG: 3.98 ± 3.27 vs. CG: 3.93 ± 3.20, p = .948, Cohen's d = 0.015), and life satisfaction (IG: 6.56 ± 1.70 vs. CG: 6.67 ± 2.09, p = .783, Cohen's d = -0.058). After surgery, participants in both IG and CG showed improved the levels of anxiety (GAD-7: IG 2.18 ± 1.21; CG 2.87 ± 2.00) and life satisfaction (LSIZ: IG 9.84 ± 2.09; CG 9.02 ± 2.15). A stratified analysis of patients with generalized anxiety disorder showed improved anxiety (GAD-7: IG 3.50 ± 1.22 vs. CG 6.80 ± 2.05, p = .017, Cohen's d = -1.956) and lower pain level (VAS: IG 4.50 ± 1.76 vs. CG 7.00 ± 1.00, p = .017, Cohen's d = -1.747) in the IG than the CG after surgery. CONCLUSIONS: Discourse-based psychological intervention before surgery can improve perioperative anxiety and life satisfaction, and postoperative painful condition, especially for patients with high-leveled pre-surgical anxiety.

Quantitative Förster Resonance Energy Transfer: Efficient Light Harvesting for Sequential Photo-Thermo-Electric Conversion.

Light is essential to all life on the earth. Thus, highly efficient light-harvesting systems with the sequential energy transfer process are significant for using solar energy in photosynthesis. For developing an efficient light-harvesting system, a liquid aggregation-induced emission (AIE) dye TPE-EA is obtained, as a donor and solvent, which can light up the aggregation caused quenching (ACQ) Nile Red (NiR, acceptor) to construct a quantitative Förster resonance energy transfer (FRET) system in NiR⊂TPE-EA. Impressively, this FRET pair shows an impressive photothermal effect, producing a peak temperature of 119 °C while excited by UV light, with 37.8% of conversion efficiency. NiR⊂TPE-EA is quite different from most other photothermal materials, which require excitation with long wavelength light (>520 nm). Therefore, NiR⊂TPE-EA firstly converts the solar into thermal energy and then into electric energy to achieve sequential photo-thermo-electric conversion. Such sequential conversion, suitable for being excited by sunlight, is anticipated to unlock new and smart approaches for capturing solar energy.

Effect of Side Chain Substituent Volume on Thermoelectric Properties of IDT-Based Conjugated Polymers.

A p-type thermoelectric conjugated polymer based on indacenodithiophene and benzothiadiazole is designed and synthesized by replacing normal aliphatic side chains (P1) with conjugated aromatic benzene substituents (P2). The introduced bulky substituent on P2 is detrimental to form the intensified packing of polymers, therefore, it hinders the efficient transporting of the charge carriers, eventually resulting in a lower conductivity compared to that of the polymers bearing aliphatic side chains (P1). These results reveal that the modification of side chains on conjugated polymers is crucial to rationally designed thermoelectric polymers with high performance.

Polar Side Chain Effects on the Thermoelectric Properties of Benzo[1,2-b:4,5-b']Dithiophene-Based Conjugated Polymers.

The molecular structure of polymers has a great influence on their thermoelectric properties; however, the relationship between the molecular structure of a polymer and its thermoelectric properties remains unclear. In this work, two benzo[1,2-b:4,5-b']dithiophene (BDT)-based conjugated polymers are designed and synthesized, which contain alkyl side chains or polar side chains. The effects of the polymer side chain on the physicochemical properties are systematically investigated, especially the thermoelectric performance of the polymers after doping with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone and 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane. It is found that the BDT-based conjugated polymer with polar side chains exhibits good miscibility with the dopants, leading to higher thermoelectric properties than those of the polymer with alkyl side chains. This work can serve as a reference for the future design of high-performance organic thermoelectric polymers.

Viscoelastic Conjugated Polymer Fluids.

The introduction of optoelectronic functions into viscoelastic polymers can yield highly sophisticated soft materials for biomedical devices and autonomous robotics. However, viscoelasticity and excellent optoelectronic properties are difficult to achieve because the presence of a large number of π-conjugated moieties drastically stiffens a polymer. Here, we report a variation of additive-free viscoelastic conjugated polymers (VE-CPs) at room temperature by using an intact π-conjugated backbone and bulky, yet flexible, alkyl side chains as "internal plasticizers." Some of these polymers exhibit gel- and elastomer-like rheological behaviors without cross-linking or entanglement. Furthermore, binary blends of these VE-CPs exhibit a never-seen-before dynamic miscibility with self-restorable and mechanically induced fluorescence color changes.

Side-Chain Effects on the Thermoelectric Properties of Fluorene-Based Copolymers.

Three conjugated polymers with alkyl chains of different lengths are designed and synthesized, and their structure-property relationship as organic thermoelectric materials is systematically elucidated. All three polymers show similar photophysical properties, thermal properties, and mechanical properties; however, their thermoelectric performance is influenced by the length of their side chains. The length of the alkyl chain significantly influences the electrical conductivity of the conjugated polymers, and polymers with a short alkyl chain exhibit better conductivity than those with a long alkyl chain. The length of the alkyl chain has little effect on the Seebeck coefficient. Only a slight increase in the Seebeck coefficient is observed with the increasing length of the alkyl chain. The purpose of this study is to provide comprehensive insight into fine-tuning the thermoelectric properties of conjugated polymers as a function of side-chain engineering, thereby providing a novel perspective into the design of high-performance thermoelectric conjugated polymers.

Solvatochromic fluorescent probes for recognition of human serum albumin in aqueous solution: Insights into structure-property relationship.

Human serum albumin (HSA) as the most abundant protein in human blood plasma, serves many physiological functions. The dysregulation of HSA in serum or in urine is associated with various diseases, such as cirrhosis of liver, multiple myeloma, and cardiovascular disease. Therefore, to quantify HSA in body fluids with high selectivity and sensitivity is of great significance for disease diagnosis and preventive medicine. We herein developed a series of amide-functionalized flavonoids probes, 1-3, for recognition of human serum albumin. All flavonoids could be easily prepared by a Claisen-Schmidt condensation and Algar-Flynn-Oyamada reaction, and showed positive solvatochromism on their dual emissions. The chemical structure of flavonoids played an important role on their HSA-sensing abilities. Among three probes, the compound 1 showed the highest sensitivity, the remarkable selectivity, and the quantitive response for HSA in aqueous solution. Together with its high tolerance of environmental pH, anti-interference properties, and time-insensitivity, thus it provides a promising sensing method for HSA.

Picket-fence polythiophene and its diblock copolymers that afford microphase separations comprising a stacked and an isolated polythiophene ensemble.

All-polythiophene diblock copolymers, comprising one unsheathed block and one fenced block, were synthesized through catalyst-transfer polycondensation. The unsheathed block self-assembles through π-π stacking, thereby inducing microphase separation. Consequently, we have succeeded in creating a microphase separation comprising an ensemble of stacked and isolated polythiophenes. This achievement could be extended to various unexplored applications as a result of the integration of the contrasting functions of the two blocks.

The Enhanced Thermoelectric and Mechanical Performance of Polythiophene/Single-Walled Carbon Nanotube Composites with Polar Ethylene Glycol Branched-Chain Modifications.

In order to develop flexible thermoelectric materials with thermoelectric and mechanical properties, in this study, we designed and synthesized polythiophene derivatives with branched ethylene glycol polar side-chains named P3MBTEMT, which were used in combination with single-walled carbon nanotubes (SWCNTs) to prepare composite thin films and flexible thermoelectric devices. A comparison was made with a polymer named P3(TEG)T, which has a polar alkoxy linear chain. The UV-vis results indicated that the larger steric hindrances of the branched ethylene glycol side-chain in P3MBTEMT could inhibit its self-aggregation and had a stronger interaction with the SWCNTs compared to that of P3(TEG)T, which was also confirmed using Raman spectroscopy. When the mass ratio of SWCNTs to P3MBTEMT was 9:1 (represented as P3MBTEMT/SWCNTs-0.9), the composite film exhibited the highest thermoelectric properties with a power factor of 446.98 µW m-1 K-2, which was more than two times higher than that of P3(TEG)T/SWCNTs-0.9 (215.08 µW m-1 K-2). The output power of the thermoelectric device with P3MBTEMT/SWCNTs-0.9 was 2483.92 nW at 50 K, which was 1.66 times higher than that of P3(TEG)T/SWCNTs-0.9 (1492.65 nW). Furthermore, the P3MBTEMT/SWCNTs-0.5 showed superior mechanical properties compared to P3(TEG)T/SWCNTs-0.5. These results indicated that the mechanical and thermoelectric performances of polymer/SWCNT composites could be significantly improved by adding polar branched side-chains to conjugated polymers. This study provided a new strategy for creating high-performing novel flexible thermoelectric materials.

Enhanced Thermoelectric Performance of Indacenodithiophene-Benzothiadiazole Copolymer Containing Polar Side Chains and Single Wall Carbon Nanotubes Composites.

Composite films of indacenodithiophene-bezothiadazole copolymers bearing polar side chains (P1) and single wall carbon nanotubes (SWCNTs) are found to show a competitive thermoelectric performance compared to their analogous polymers with aliphatic side chains (P2). The enhanced power factors could be attributed to the stronger interfacial interactions between the P1/SWCNTs compared to that of P2/SWCNTs containing the same ratio of SWCNTs. A maximum power factor of 161.34 µW m-1 K-2 was obtained for the composite films of P1/SWCNTs for a filler content of 50 wt%, which is higher than that of P2/SWCNTs (139.06 µW m-1 K-2, 50 wt%). Our work sheds light on the design of side-chains in efficient conjugated polymers/SWCNTs thermoelectric materials and contributes to the understanding of their thermoelectric properties.

Structure and Doping Optimization of IDT-Based Copolymers for Thermoelectrics.

π-conjugated backbones play a fundamental role in determining the thermoelectric (TE) properties of organic semiconductors. Understanding the relationship between the structure-property-function can help us screen valuable materials. In this study, we designed and synthesized a series of conjugated copolymers (P1, P2, and P3) based on an indacenodithiophene (IDT) building block. A copolymer (P3) with an alternating donor-acceptor (D-A) structure exhibits a narrower band gap and higher carrier mobility, which may be due to the D-A structure that helps reduce the charge carrier transport obstacles. In the end, its power factor reaches 4.91 µW m-1 K-2 at room temperature after doping, which is superior to those of non-D-A IDT-based copolymers (P1 and P2). These results indicate that moderate adjustment of the polymer backbone is an effective way to improve the TE properties of copolymers.

Boosting the Power Factor of Benzodithiophene Based Donor-Acceptor Copolymers/SWCNTs Composites through Doping.

In this study, a benzodithiophene (BDT)-based donor (D)-acceptor (A) polymer containing carbazole segment in the side-chain was designed and synthesized and the thermoelectric composites with 50 wt % of single walled carbon nanotubes (SWCNTs) were prepared via ultrasonication method. Strong interfacial interactions existed in both of the composites before and after immersing into the 2,3,5,6-Tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ) solution as confirmed by UV-Vis-NIR, Raman, XRD and SEM characterizations. After doping the composites by F4TCNQ, the electrical conductivity of the composites increased from 120.32 S cm-1 to 1044.92 S cm-1 in the room temperature. With increasing the temperature, the electrical conductivities and Seebeck coefficients of the undoped composites both decreased significantly for the composites; the power factor at 475 K was only 6.8 µW m-1 K-2, which was about nine times smaller than the power factor at room temperature (55.9 µW m-1 K-2). In the case of doped composites, although the electrical conductivity was deceased from 1044.9 S cm-1 to 504.17 S cm-1, the Seebeck coefficient increased from 23.76 µV K-1 to 35.69 µW m-1 K-2, therefore, the power factors of the doped composites were almost no change with heating the composite films.

Preparation and Thermoelectric Properties Study of Bipyridine-Containing Polyfluorene Derivative/SWCNT Composites.

Polymer/inorganic thermoelectric composites have witnessed rapid progress in recent years, but most of the studies have focused on the traditional conducting polymers. The limited structures of traditional conducting polymers restrain the development of organic thermoelectric composites. Herein, we report the preparation and thermoelectric properties of a series of composites films based on SWCNTs and bipyridine-containing polyfluorene derivatives. The value of the power factor around 12 µW m-1 K-2 was achieved for the composite F8bpy/SWCNTs with a mass ratio of 50/50, and the maximum value of 62.3 µW m-1 K-2 was obtained when the mass ratio reached 10/90. Moreover, taking advantage of the bipyridine unit could chelate various kinds of metal ions to form polymer complexes. The enhanced power factor of 87.3 µW m-1 K-2 was obtained for composite F8bpy-Ni/SWCNTs with a mass ratio of 50/50. Finally, the thermoelectric properties of the bipyridine-containing polyfluorene derivative/SWCNT composites were conveniently tuned by chelating with different metal ions.

A flavonoid-based fluorescent test strip for sensitive and selective detection of a gaseous nerve agent simulant.

Developing fluorescent sensors with ability of monitoring gaseous nerve agents in a sensitive and selective manner is of great importance due to the extreme toxicity and volatility of organophosphorus nerve agents. Herein we reported a novel oxime-modified flavonoid sensor and carefully investigated its sensing behavior towards nerve agent simulants, diethylchlorophosphate (DCP). In the presence of DCP, a remarkable fluorescence enhancement accompanied with emission color change could be observed by naked eyes in solution. The response time was less than 90 s and LOD value was calculated as 0.78 µmol/L in solution. The sensing mechanism could be ascribed to the specific reaction between halophosphate and hydroxyl group of oxime. Furthermore, sensor strips have been successfully constructed by using PEG as matrix with a simple preparation process, and also achieved the sensitive and selective detection of DCP vapor. These results in this study may provide important references for further design of dye-based sensor strips for detection of nerve agents both in solution and gas phase.

Preparation of Luminescent Thermotropic Liquid Crystal from Benzodiathiazole Derivatives.

Luminescent liquid crystal materials (LLCMs) have been a hot research topic in the field of fluorescent materials. In this study, we successfully designed and synthesized an intense fluorescence thermotropic liquid crystal material with a fluorescence quantum yield (Φ) of 0.26 in the solid state. Moreover, the alkyl chain attached to the terminus of the chromophore was able to promote the stability of electrochemical and thermal properties, which was beneficial to the device fabrication reproducibility and stability of the device performance.

Boosting the Adhesivity of π-Conjugated Polymers by Embedding Platinum Acetylides towards High-Performance Thermoelectric Composites.

Single-walled carbon nanotubes (SWCNTs) incorporated with π-conjugated polymers, have proven to be an effective approach in the production of advanced thermoelectric composites. However, the studied polymers are mainly limited to scanty conventional conductive polymers, and their performances still remain to be improved. Herein, a new planar moiety of platinum acetylide in the π-conjugated system is introduced to enhance the intermolecular interaction with the SWCNTs via π⁻π and d⁻π interactions, which is crucial in regulating the thermoelectric performances of SWCNT-based composites. As expected, SWCNT composites based on the platinum acetylides embedded polymers displayed a higher power factor (130.7 ± 3.8 µW·m-1·K-2) at ambient temperature than those without platinum acetylides (59.5 ± 0.7 µW·m-1·K-2) under the same conditions. Moreover, the strong interactions between the platinum acetylide-based polymers and the SWCNTs are confirmed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) measurements.

High-Performance N-Type Carbon Nanotube Composites: Improved Power Factor by Optimizing the Acridine Scaffold and Tailoring the Side Chains.

Single-walled carbon nanotubes (SWCNTs)/organic small molecules (OSMs) are promising candidates for application in thermoelectric (TE) modules; however, the development of n-type SWCNT/OSMs with high performance is lagging behind. Only a few structure-activity relationships of OSMs on SWCNT composites have been reported. Recently, we find that the n-type acridone/SWCNT composites display high power factor (PF) values at high temperature but suffer from low PFs at room temperature. Here, the performance of SWCNT composites containing an acridine derivative (AD) as well as its analogues with different counterions (Cl-, SO42- and F-) and lengths of alkyl chains (ADLA1-2 and ADLA4-5) is reported. Among the composites, SWCNT/ADLA4 with no counterions exhibits the highest PF value of 195.2 µW m-1 K-2 at room temperature, which is 4.9 times higher than that of SWCNT/ADTAd (39.8 µW m-1 K-2), indicating that the acridine scaffold and the lengths of alkyl chains contribute to the dramatic changes in the TE performance. In addition, SWCNT/ADLA4 exhibits high PF values at all the temperatures we investigate, which range from 154.7 to 230.7 µW m-1 K-2. Furthermore, a TE device consisting of five pairs of p (the pristine SWCNTs)-n (SWCNT/ADLA4) junctions is assembled, generating a relatively high open-circuit voltage (41.7 mV) and an output power of 1.88 µW at a temperature difference of 74.8 K. Our results suggest that structural modifications might be an effective way to advance the development of TE materials.

Enhanced Electroluminescence from a Thiophene-Based Insulated Molecular Wire.

We report on the realization of polymer light-emitting diodes (PLEDs) based on fluorescent polythiophene (PT)-based insulated molecular wires (IMWs). PLEDs using PT emitting layers traditionally have low external quantum efficiencies (ηeqe) below 0.1%. Moreover, IMWs lack a thorough exploitation for electroluminescent applications due to concerns about reduced charge transport between their chains. We constructed multilayer PLEDs containing PT IMW emitting layers that show the maximum ηeqe close to 1.4%, luminance at 3700 cd/m2, and low turn on voltage at 2.5 V. We also show a strong influence of the thickness of electron transport layer on ηeqe through device optimization and optical simulations.

Conjugated Oligomers and Polymers Sheathed with Designer Side Chains.

Conjugated polymers (CPs) are often referred to as molecular wires because of their quasi one-dimensional electronic wavefunctions delocalized along the polymer chains. However, in the solid state, CPs tend to self-assemble through π-stacking, which greatly attenuates the one-dimensional nature. By molecular design, CPs can be molecularly insulated just like electric power cords, resulting in so-called "insulated" molecular wires (IMWs). In this Focus Review, we will discuss their unique photophysical, electronic, and mechanical properties which originate from the absence of π-stacking.