Delocalizing electron distribution in thermally activated delayed fluorophors for high-efficiency and long-lifetime blue electroluminescence.

Blue thermally activated delayed fluorescent emitters are promising for the next generation of organic light-emitting diodes, yet their performance still cannot meet the requirements for commercialization. Here we establish a design rule for highly efficient and stable thermally activated delayed fluorescent emitters by introducing an auxiliary acceptor that could delocalize electron distributions, enhancing molecular stability in both the negative polaron and triplet excited state, while also accelerating triplet-to-singlet up-conversion and singlet radiative processes simultaneously. Proof-of-concept thermally activated delayed fluorescent compounds, based on a multi-carbazole-benzonitrile structure, exhibit near-unity photoluminescent quantum yields, short-lived delays and improved photoluminescent and electroluminescent stabilities. A deep-blue organic light-emitting diode using one of these molecules as a sensitizer for a multi-resonance emitter achieves a remarkable time to 95% of initial luminance of 221 h at an initial luminance of 1,000 cd m-2, a maximum external quantum efficiency of 30.8% and Commission Internationale de l'Eclairage coordinates of (0.14, 0.17).

Molecular-Level Insight into Impact of Additives on Film Formation and Molecular Packing in Y6-based Organic Solar Cells.

Additive engineering is widely utilized to optimize film morphology in active layers of organic solar cells (OSCs). However, the role of additive in film formation and adjustment of film morphology remains unclear at the molecular level. Here, taking high-efficiency Y6-based OSC films as an example, this work thus employs all-atom molecular-dynamics simulations to investigate how introduction of additives with different π-conjugation degree thermodynamically and dynamically impacts nanoscale molecular packings. These results demonstrate that the van der Waals (vdW) interactions of the Y6 end groups with the studied additives are strongest. The larger the π-conjugation degree of the additive molecules, the stronger the vdW interactions between additive and Y6 molecules. Due to such vdW interactions, the π-conjugated additive molecules insert into the neighboring Y6 molecules, thus opening more space for relaxation of Y6 molecules to trigger more ordered packing. Increasing the interactions between the Y6 end groups and the additive molecules not only accelerates formation of the Y6 ordered packing, but also induces shorter Y6-intermolecular distances. This work reveals the fundamental molecular-level mechanism behind film formation and adjustment of film morphology via additive engineering, providing an insight into molecular design of additives toward optimizing morphologies of organic semiconductor films.

Tension Induced Photoluminescence Enhancement in an Organic Single Crystal.

Organic single crystals possess distinct advantages due to their highly ordered molecular structures, resulting in improved stability, enhanced carrier mobility, and superior optical characteristics. However, their mechanical rigidity and brittleness impede the applications in flexible and wearable optoelectronic devices. Here, photoluminescence (PL) emission from 2,6-diphenylanthracene (DPA) single crystals is studied under tensile strain, which shows PL enhancement by more than two times with a strain of ≈1.42%. Such a tension induced PL enhancement is reversible, exhibiting no clear optical degradations during 100 cycles of bending and recovery processes. Theoretical calculations reveal that the deformation of molecular structure under strain induces a decrease of the dihedral between anthracene and benzene moieties in DPA molecules. Further, the increased molecular conjugation enhances the molecular oscillator strength, leading to the brightened PL emission. Meanwhile, with the decreased dihedral, the molecular vibrations in DPA crystals are suppressed, which can reduce the non-radiative decay rate. In contrast, no tension induced PL enhancement is observed in polycrystalline DPA thin films as the strain can be released via the grain boundaries. This study highlights the superior optical performance of DPA single crystals under strain field, which will provide new possibilities for DPA-based flexible devices.

Conversion chemoradiotherapy combined with nab-paclitaxel plus cisplatin in patients with locally advanced borderline-resectable or unresectable esophageal squamous cell carcinoma: a phase i/ii prospective cohort study.

BACKGROUND: To evaluate the efficacy and safety of nab-paclitaxel plus cisplatin as the regimen of conversional chemoradiotherapy (cCRT) in locally advanced borderline resectable or unresectable esophageal squamous cell carcinoma (ESCC). METHODS: Patients with locally advanced ESCC (cT3­4, Nany, M0­1, M1 was limited to lymph node metastasis in the supraclavicular area) were enrolled. All the patients received the cCRT of nab-paclitaxel plus cisplatin. After the cCRT, those resectable patients received esophagectomy; those unresectable patients continued to receive the definitive chemoradiotherapy (dCRT). The locoregional control (LRC), overall survival (OS), event-free survival (EFS), distant metastasis free survival (DMFS), pathological complete response (pCR), R0 resection rate, adverse events (AEs) and postoperative complications were calculated. RESULTS: 45 patients with ESCC treated from October 2019 to May 2021 were finally included. The median follow-up time was 30.3 months. The LRC, OS, EFS, DMFS at 1 and 2 years were 81.5%, 86.6%, 64.3%, 73.2 and 72.4%, 68.8%, 44.8%, 52.7% respectively. 21 patients (46.7%) received conversional chemoradiotherapy plus surgery (cCRT+S). The pCR rate and R0 resection rate were 47.6 and 84.0%. The LRC rate at 1 and 2 years were 95.0%, 87.1% in cCRT+S patitents and 69.3%, 58.7% in dCRT patients respectively (HR, 5.14; 95%CI, 1.10-23.94; P = 0.021). The toxicities during chemoradiotherapy were tolerated, and the most common grade 3-4 toxicitiy was radiation esophagitis (15.6%). The most common postoperative complication was pleural effusion (38.1%) and no grade ≥ IIIb complications were observed. CONCLUSION: nab-paclitaxel plus cisplatin are safe as the regimen of conversional chemoradiotherapy of ESCC.

Isomeric Dimer Acceptors for Stable Organic Solar Cells with over 19% Efficiency.

The strategy of isomerization is known for its simple yet effective role in optimizing molecular configuration and enhancing the power conversion efficiency (PCE) of organic solar cells (OSCs). However, the impact of isomerization on the design of dimer acceptors has been rarely investigated, and the relationship between the chemical structure and optoelectronic property remains unclear. In this study, we designed and synthesized two dimer acceptor isomers named D-TPh and D-TN, which differ in the positional arrangement of their end capping groups. Compared to D-TN, D-TPh exhibited enhanced backbone planarity, elevated lowest unoccupied molecular orbital energy level, and more ordered molecular stacking. Consequently, the OSC device based on PM6:D-TPh achieved a PCE of 19.05%, higher than that (PCE = 18.42%) of the device based on PM6:D-TN. Large-area PM6:D-TPh devices (1 cm²) yielded a PCE of 18.0%. More importantly, the extrapolated T80 lifetime of the PM6:D-TPh device is over 2800 h with MPP tracking under continuous one-sun illumination. These results suggest that isomerization strategy is an effective way to optimize the molecular configuration of dimer acceptors for the fabrication of high-efficiency and stable OSCs.

Manipulation of the Self-Assembly Morphology by Side-Chain Engineering of Quinoxaline-Substituted Organic Photothermal Molecules for Highly Efficient Solar-Thermal Conversion and Applications.

Organic photothermal materials have attracted increasing attention because of their structural diversity, flexibility, and compatibility. However, their energy conversion efficiency is limited owing to the narrow absorption spectrum, strong reflection/transmittance, and insufficient nonradiative decay. In this study, two quinoxaline-based D-A-D-A-D-type molecules with ethyl (BQE) or carboxylate (BQC) substituents were synthesized. Strong intramolecular charge transfer provided both molecules with a broad absorption range of 350-1000 nm. In addition, the high reorganization energy and weak molecular packing of BQE resulted in efficient nonradiative decay. More importantly, the self-assembly of BQE leads to a textured surface and enhances the light-trapping efficiency with significantly reduced light reflection/transmittance. Consequently, BQE achieved an impressive solar-thermal conversion efficiency of 18.16 % under 1.0 kW m-2 irradiation with good photobleaching resistance. Based on this knowledge, the water evaporation rate of 1.2 kg m-2 h-1 was attained for the BQE-based interfacial evaporation device with an efficiency of 83 % under 1.0 kW m-2 simulated sunlight. Finally, the synergetic integration of solar-steam and thermoelectric co-generation devices based on BQE was realized without significantly sacrificing solar-steam efficiency. This underscores the practical applications of BQE-based technology in effectively harnessing photothermal energy. This study provides new insights into the molecular design for enhancing light-trapping management by molecular self-assembly, paving the way for photothermal-driven applications of organic photothermal materials.

Spin-coated and vacuum-processed hole-extracting self-assembled multilayers with H-aggregation for high-performance inverted perovskite solar cells.

We report a highly crystalline self-assembled multilayer (SAMUL) that is fundamentally different from the conventional monolayer or disordered bilayer used for hole-extraction in inverted perovskite solar cells (PSCs). The SAMUL can be easily formed on ITO substrate to form better surface coverage for enhancing the performance and stability of PSCs. A detailed structure-property-performance relationship of molecules used for SAMUL is established through a systematic study of their crystallinity, molecular packing, and hole-transporting properties. These SAMULs are rationally optimized by varying their molecular structures and deposition through thermal evaporation or spin-coating for fabricating PSCs. The CbzNaphPPA-based SAMUL was chosen for fabricating inverted PSCs due to its highest crystallinity and hole mobility derived from the ordered H-aggregation, which resulted in a remarkably high fill factor of 86.45%. This enables a very impressive power conversion efficiency (PCE) of 26.07% to be achieved along with excellent device stability (94% of its initial PCE retained after continuous operation for 1200 h under 1-sun irradiation at maximum power point at 65°C). Additionally, a record-high PCE of 23.50% could be achieved by adopting a thermally evaporated SAMUL. This greatly simplifies and broadens the scope for SAM to be used for large-area devices on diverse substrates.

Frenkel and Charge-Transfer Excitonic Couplings Strengthened by Thiophene-Type Solvent Enables Binary Organic Solar Cells with 19.8 % Efficiency.

Overcoming the trade-off between short-circuited current (Jsc) and open-circuited voltage (Voc) is important to achieving high-efficiency organic solar cells (OSCs). Previous works modulated the energy gap between Frenkel local exciton (LE) and charge-transfer (CT) exciton, which served as the driving force of exciton splitting. Differently, our current work focuses on the modulation of LE-CT excitonic coupling (tLE-CT) via a simple but effective strategy that the 2-chlorothiophene (2Cl-Th) solvent utilizes in the treatment of OSC active-layer films. The results of our experimental measurements and theoretical simulations demonstrated that 2Cl-Th solvent initiates tighter intermolecular interactions with non-fullerene acceptor in comparison with that of traditional chlorobenzene solvent, thus suppressing the acceptor's over-aggregation and retarding the acceptor crystallization with reduced trap. Critically, the resulting shorter distances between donor and acceptor molecules in the 2Cl-Th treated blend efficiently strengthen tLE-CT, which not only promotes exciton splitting but also reduces non-radiative recombination. The champion efficiencies of 19.8 % (small-area) with superior operational reliability (T80: 586 hours) and 17.0 % (large-area) were yielded in 2Cl-Th treated cells. This work provided a new insight into modulating the exciton dynamics to overcome the trade-off between Jsc and Voc, which can productively promote the development of the OSC field.

Stepwise One-Shot Borylation Reactions for Intersecting DABNA Substructures Exhibiting Bright Yellow‒Green Electroluminescence with EQE Beyond 40% and Mild Roll-Off.

Boron/nitrogen (B/N)-doped polycyclic aromatic hydrocarbons (PAHs) with the multiple resonance (MR) effect are promising for organic light-emitting diodes (OLEDs) because of their narrowband emission and thermally activated delayed fluorescence (TADF) characteristics. Nevertheless, exploring the variety of such emitters is challenging because of the tricky and limited synthetic protocols. Herein, we designed a novel B/N-doped PAH, L-DABNA-1, whose backbone (L-DABNA) could not be achieved via conventional routes (e.g., one-pot borylation or one-shot borylation). We successfully synthesized it through stepwise one-shot borylations with precisely introducing decorations. The unique MR backbone with intersecting DABNA substructures sharing an aniline group, avoiding any para-N-π-B motif, allows L-DABNA-1 to maintain narrowband TADF emission while significantly redshifting to the yellow-green region with a reverse intersystem crossing rate (kRISC) of 1.28 × 105 s-1. An L-DABNA-1-based OLED device achieved a maximum external quantum efficiency (EQE) of over 40% and maintained a high EQE of 36.3% at 1000 cd m-2, with a current efficiency reaching ~170 cd A-1. This work not only demonstrated the great potential of stepwise borylations in synthesizing B/N-doped PAH backbones, expanding their chemical space, but also provided a promising pathway for exploring MR-TADF emitters at longer wavelengths.

Mapping of Lymph Node Metastasis From Thoracic Esophageal Cancer: A Retrospective Study.

OBJECTIVES: This retrospective study was designed to investigate the optimal extent of dissection for thoracic esophageal cancer (EC) based on the incidence of lymph node metastasis (LNM). METHODS: We retrospectively identified 1014 patients with thoracic esophageal carcinoma who underwent esophagectomy at our institution between May 2018 and November 2020. Also, the location and rate of LNM in relation to the postoperative pathological results were retrieved. We separately counted the metastasis rates of routinely excised lymph node stations according to the Japan Esophageal Society (JES) staging system. RESULTS: A total of 1666 consecutive patients were screened, and 1014 were enrolled. Generally, the rates of LNM in thoracic EC may be arranged in the descending order of station 7 > station 106recR > station 2 > station 106recL. Esophageal cancer in the middle and lower thoracic segment also had a high rate of LNM along bilateral recurrent laryngeal nerve. Stations 106tbL and 111 were the lowest frequent sites of metastasis with rate less than 5%; only the patients with clinically positive LNs need to dissect. The cT3-4, cN+, or G3 were independent risk factors for LNM and neoadjuvant therapy did not change the distribution of LNM for thoracic EC cases. CONCLUSIONS: This study accurately identified the distribution of LNM for thoracic EC patients. Neoadjuvant therapy could not change the overall distribution of LNM in thoracic EC patients. However, whether LNs dissection at stations 106tbL and 111 is related to the survival of thoracic EC or not, needs a long follow-up time to verify.

Reconstruction of upper mediastinal pleura reduces postoperative complications in enhanced recovery surgery system after esophagectomy: A propensity score matching study.

OBJECTIVES: This study aimed to explore the effect of suturing upper mediastinum pleura on postoperative complications, surgery-related mortality, and hospital stay. METHODS: Four hundred and thirty-eight patients with esophageal cancer who underwent esophagectomy were identified. Patients were divided into two groups: those in the test group who received reconstruction of upper mediastinal pleura, those in the conventional group who did not. The incidence of postoperative complications, surgery-related mortality, and hospital stay were compared. To reduce the impact of confounding factors, a propensity score matching (PSM) method was performed. RESULTS: A total of 273 patients were treated with suturing upper mediastinal pleura and 165 were not. After PSM, compared with the conventional group, the incidence of atelectasis (7.2% vs. 1.4%, p = 0.035), anastomotic leakage (5.8% vs. 0.7%, p = 0.036), and delayed gastric emptying (10.8% vs. 3.6%, p = 0.034) were significantly lower in the test group. And suturing the upper mediastinal pleura could reduce the severity of leakage (p = 0.045), consistent with the results before PSM. Moreover, there were no significant differences in the incidence of other complications, postoperative hospital stay, and 30-day mortality (all p > 0.05). CONCLUSIONS: In this study, suturing the upper mediastinal pleura can reduce the incidence of atelectasis, anastomotic leakage, and delayed gastric emptying, and the severity of leakage, without increasing the incidence of other complications, surgery-related death, and postoperative hospital stay.

Critical role of intermediate electronic states for spin-flip processes in charge-transfer-type organic molecules with multiple donors and acceptors.

Spin-flip in purely organic molecular systems is often described as a forbidden process; however, it is commonly observed and utilized to harvest triplet excitons in a wide variety of organic material-based applications. Although the initial and final electronic states of spin-flip between the lowest singlet and lowest triplet excited state are self-evident, the exact process and the role of intermediate states through which spin-flip occurs are still far from being comprehensively determined. Here, via experimental photo-physical investigations in solution combined with first-principles quantum-mechanical calculations, we show that efficient spin-flip in multiple donor-acceptor charge-transfer-type organic molecular systems involves the critical role of an intermediate triplet excited state that corresponds to a partial molecular structure of the system. Our proposed mechanism unifies the understanding of the intersystem crossing mechanism in a wide variety of charge-transfer-type molecular systems, opening the way to greater control over spin-flip rates.

High stability and luminescence efficiency in donor-acceptor neutral radicals not following the Aufbau principle.

With their unusual electronic structures, organic radical molecules display luminescence properties potentially relevant to lighting applications; yet, their luminescence quantum yield and stability lag behind those of other organic emitters. Here, we designed donor-acceptor neutral radicals based on an electron-poor perchlorotriphenylmethyl or tris(2,4,6-trichlorophenyl)methyl radical moiety combined with different electron-rich groups. Experimental and quantum-chemical studies demonstrate that the molecules do not follow the Aufbau principle: the singly occupied molecular orbital is found to lie below the highest (doubly) occupied molecular orbital. These donor-acceptor radicals have a strong emission yield (up to 54%) and high photostability, with estimated half-lives reaching up to several months under pulsed ultraviolet laser irradiation. Organic light-emitting diodes based on such a radical emitter show deep-red/near-infrared emission with a maximal external quantum efficiency of 5.3%. Our results provide a simple molecular-design strategy for stable, highly luminescent radicals with non-Aufbau electronic structures.

Sarcopenia and Short-Term Outcomes After Esophagectomy: A Meta-analysis.

BACKGROUND: This meta-analysis aimed to investigate the value of preoperative sarcopenia in predicting complications after esophagectomy. Clinicopathologic characteristics of sarcopenia patients, which may support sarcopenia management, also were studied. METHODS: This study searched for articles describing an association between sarcopenia and short-term outcomes after esophagectomy using PubMed, EMBASE, and the Cochrane Library. Mantel-Haenszel and inverse variance models were used for the meta-analyses of end points. RESULTS: The meta-analysis included 14 studies comprising a total of 2387 patients. Sarcopenia was significantly associated with advanced age (weighted mean difference [WMD], 3.48; 95% confidence interval [CI], 2.22-4.74), lower body mass index (WMD - 2.22; 95% CI - 2.65 to - 1.79), squamous cell carcinoma (odds ratio [OR], 2.78; 95% CI 1.72-4.47), advanced clinical tumor stage (OR 1.65; 95% CI 1.28-2.15), and neoadjuvant therapy (OR 1.87; 95% CI 1.38-2.53). The sarcopenia patients showed lower preoperative albumin levels (WMD - 0.11; 95% CI - 0.19 to - 0.04) than the nonsarcopenia patients. Sarcopenia was significantly predictive of pneumonia (OR 2.58; 95% CI 1.75-3.81) and overall complications (OR 1.52; 95% CI 1.07-2.15) after esophagectomy. The sarcopenia patients also showed nonsignificant increases in the risks of anastomotic leakage (OR 1.29; 95% CI 0.99-1.67), vocal cord palsy (OR 2.03; 95% CI 0.89-4.64), and major complications (≥ Clavien-Dindo grade III; OR 1.30; 95% CI 0.95-1.79) but not increased operation time, blood loss, or mortality. CONCLUSIONS: Preoperative sarcopenia assessment showed considerable potential for predicting postoperative complications for esophageal cancer patients. To realize this potential, more effective diagnostic criteria and severity classifications for sarcopenia are warranted.

An Observational Study: Is N-Acetylcysteine Helpful in Performance Improvement of Mycoplasma IST2 Testing through Sample Homogenization?

BACKGROUND: Culture is still the gold standard for the detection of genital mycoplasma which could cause urogenital infections in humans. Mycoplasma IST2 is a commercial kit widely used for the detection of M. hominis and Ureaplasma species. Its accuracy was partially impaired because clinical specimens are usually mixed with purulent or transparent mucus. We aimed to solve this problem through sample homogenization by N-acetylcysteine (NAC) treatment. METHODS: Twenty-two endocervical swab samples were collected from 22 female patients with suspected mycoplasma infection, while 11 of these specimens were with purulent or transparent mucus. Mycoplasma IST2 testing kit was used for mycoplasma culture and AST for the control group and NAC-treated group. RESULTS: Genital mycoplasma was detected in 15 of 22 samples for both groups. The colony number in 6 out of 11 purulent specimens (54.5%) was more than 104 CFU/ml of genital mycoplasma for the NAC-treated group, while only one of 11 (9.1%) for the control group. For the nonpurulent specimens, no significant difference had been found in colony counting of genital mycoplasma between the control group and NAC-treated group (P > 0.05). The results of antimicrobial susceptibility testing for the NAC-treated group were highly similar to those for the control group. CONCLUSIONS: Our results demonstrate that NAC is helpful in sample homogenization and NAC treatment can improve the detection efficiency of mycoplasma with Mycoplasma IST2 testing.

Quantitative relations between interaction parameter, miscibility and function in organic solar cells.

Although it is known that molecular interactions govern morphology formation and purity of mixed domains of conjugated polymer donors and small-molecule acceptors, and thus largely control the achievable performance of organic solar cells, quantifying interaction-function relations has remained elusive. Here, we first determine the temperature-dependent effective amorphous-amorphous interaction parameter, χaa(T), by mapping out the phase diagram of a model amorphous polymer:fullerene material system. We then establish a quantitative 'constant-kink-saturation' relation between χaa and the fill factor in organic solar cells that is verified in detail in a model system and delineated across numerous high- and low-performing materials systems, including fullerene and non-fullerene acceptors. Our experimental and computational data reveal that a high fill factor is obtained only when χaa is large enough to lead to strong phase separation. Our work outlines a basis for using various miscibility tests and future simulation methods that will significantly reduce or eliminate trial-and-error approaches to material synthesis and device fabrication of functional semiconducting blends and organic blends in general.

Thermally Activated Delayed Fluorescence (TADF) Path toward Efficient Electroluminescence in Purely Organic Materials: Molecular Level Insight.

Since the seminal work of Tang and Vanslyke in 1987 on small-molecule emitters and that of Friend and co-workers in 1990 on conjugated-polymer emitters, organic light-emitting diodes (OLEDs) have attracted much attention from academia as well as industry, as the OLED market is estimated to reach the $30 billion mark by the end of 2018. In these first-generation organic emitters, on the basis of simple spin statistics, electrical excitation resulted in the formation of ∼25% singlet excitons and ∼75% triplet excitons. Radiative decay of the singlet excitons to the singlet ground state leads to a prompt fluorescence emission, while the triplet excitons only lead to weak phosphorescence due to the very small spin-orbit couplings present in purely organic molecules. The consequence is a ca. 75% energy loss, which triggered wide-ranging efforts to try and harvest as many of the triplet excitons as possible. In 1998, Thompson, Forrest, and their co-workers reported second-generation OLED emitters based on coordination complexes with heavy transition metals (e.g., iridium or platinum). Here, the triplet excitons stimulate efficient and fast phosphorescence due to the strong spin-orbit couplings enabled by the heavy-metal atoms. Internal quantum efficiencies (IQE) up to 100% have been reported, which means that for every electron injected into the device, a photon is emitted. While these second-generation emitters are those mainly exploited in current OLED applications, there is strong impetus from both cost and environmental standpoints to find new ways of exploiting purely organic emitters, which in addition can offer greater flexibility to fine-tune the electronic and optical properties by exploiting the synthetic organic chemistry toolbox. In 2012, Adachi and co-workers introduced a promising strategy, based on thermally activated delayed fluorescence (TADF), to harvest the triplet excitons in purely organic molecular materials. These materials now represent the third generation of OLED emitters. Impressive photophysical properties and device performances have been reported, with internal quantum efficiencies also reaching nearly 100%. Our objectives in this Account are threefold: (i) to lay out a comprehensive description, at the molecular level, of the fundamental photophysical processes behind TADF emitters; (ii) to discuss some of the challenges facing the design of TADF emitters, such as the need to balance the efficiency of thermal activation of triplet excitons into the singlet manifold with the efficiency of radiative transition to the ground state; and (iii) to highlight briefly some of the recent molecular-design strategies that pave the way to new classes of TADF materials.

FA01.03: USE OF 'NON-TUBE NO FASTING' ERAS PROTOCOL IN PATIENTS AFTER MIE WITH LI'S ANASTOMOSIS: OUTCOMES IN THE FIRST 113 PATIENTS PERFORMED BY A SURGEON AFTER TRAINING COURSE.

BACKGROUND: Use of enhanced recovery after surgery(ERAS) protocol in the patients after esophagectomy is reported to be feasible and safe in recent studies. And in Prof. Yin Li's research, patients after minimally invasive esophagectomy(MIE) with Li's anastomosis took oral feeding on the 1st day after operation (POD1). However, all the esophagectomy-procedures were proceeded by experienced experts. There was no report regarding whether ERAS protocol after MIE with Li's anastomosis could be safely proceeded by a young surgeon after training course. The aim of this study was to evaluate the feasibility and safety of 'Non-Tube No Fasting' ERAS Protocol in patients after MIE with Li's Anastomosis proceeded by a surgeon after the training course. METHODS: We retrospectively reviewed the clinical data of patients who underwent MIE for cancer from December 2015 to September 2017 by a new surgical team finished MIE training course in our department. During the study period, the new team performed Mckeown MIE with Li's anastomosis for 127 esophageal cancer patients. We analyzed the data of 113 patients who followed the protocol of 'Non-tube No Fasting' ERAS. The primary end-points were the incidence of anastomotic fistula, the injury of recurrent laryngeal nerve, pneumonia, and postoperative length of hospital-stay. RESULTS: All the 113 patients began oral feeding on POD1. Two patients exited the ERAS protocol on account of bucking caused by recurrent laryngeal nerve injury on POD3. The incidence of anastomotic fistula, recurrent laryngeal nerve injury and pneumonia were 3.5% (4/113), 12.4%(14/113) and 18.5%(21/113). The average length of postoperative hospital-stay was 8.6 ± 6.9 days. Both of the in-hospital mortality and 30-day mortality were 0. CONCLUSION: Our date indicated that it was feasible and safe for a selected surgeon after 'Non-tube no fasting' ERAS and MIE training courses to proceed the protocol. Of course, more clinical researches are needed to confirm this result. DISCLOSURE: All authors have declared no conflicts of interest.

Topological Transformation of π-Conjugated Molecules Reduces Resistance to Crystallization.

Two electronically delocalized molecules were designed as models to understand how molecular shape impacts the tradeoff between solubility and crystallization tendencies in molecular semiconductors. The more soluble compound TT contains a non-planar bithiophene central fragment, whereas CT has a planar cyclopentadithiophene unit. Calorimetry studies show that CT can crystallize more easily than TT. However, absorption spectroscopy shows that the initially amorphous TT film can eventually form crystals in which the molecular shape is significantly more planar. Two thermally reversible polymorphs for TT were observed by XRD and grazing-incidence wide-angle X-ray scattering (GIWAXS) measurements. These findings are relevant within the context of designing soft semiconductors that exhibit high solubility and a tendency to provide stable organized structures with desirable electronic properties.

Theoretical Study on Charge Transport Properties of Intra- and Extra-Ring Substituted Pentacene Derivatives.

A series of pentacene derivatives, halogen-substituted and thiophene- and pyridine-substituted, have been studied with a focus on the electronic properties and charge transport properties using density functional theory and classical Marcus charge-transfer theory. The transport properties of holes and electrons have been studied to get insight into the effect of halogenation and heteroatom substitution on transport and injection of charge carriers. The calculation results revealed that fluorination and chlorination can effectively lower the lowest unoccupied molecular orbital (LUMO) level, modulate the hole and electron reorganization energy, improve the stacking mode of the crystal structure, and enhance the ambipolar characteristic. Chlorination gives a better ambipolar characteristic. On the basis of halogen substitution, the substitution of terminal benzene ring of triisopropyl-silylethynyl-pentacene (TIPS-PEN) by a thiophene or pyridine will greatly lower the LUMO level and improve the stacking mode, leading to more suitable ambipolar materials. Hence, both intra- and extra-ring substitution are favorable to enhance the ambipolar transport property of TIPS-PEN.