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Abstract Highly crystalline organic semiconductors are ideal materials for photocatalytic hydrogen evolution in water splitting. However, the instability and complex synthesis processes of most reported organic molecule‐based photocatalysts restrict their applications. In this study, we introduce benzo [1,2‐b:4,5‐bʹ] bis [1] benzothiophene‐3,9‐dicarboxylic acid, 5,5,11,11‐tetraoxide (FSOCA), a highly crystalline, stable molecular crystal that is easy to synthesize and serves as an efficient photocatalyst for the hydrogen evolution reaction. FSOCA exhibits high efficiency in sacrificial hydrogen evolution reaction (760 µmol h−1, 76 mmol g−1 h−1 at 330 mW cm−2; 570 µmol h−1, 57 mmol g−1 h−1 at 250 mW cm−2), and FSOCA remains stable during photocatalysis for up to 400 h. Experiments and theoretical studies confirmed the presence of hydrogen bonds between the sulfone group and the sacrificial agent (ascorbic acid). This interaction significantly improved the oxidation reaction kinetics and boosted the photocatalytic performance. This study presents a scalable and convenient approach to synthesize highly crystalline, active, and stable organic photocatalysts with potential applications in large‐scale photocatalysis.

Objective: A method for the determination of aminophylline residues in edible tissues （muscle, liver and kidney） of pigs by solid-phase extraction combined with high performance liquid chromatography-tandem mass spectrometry was established. Methods: After extracted by methanol, the aminophylline was purified by PRiME HLB solid phase extraction column in one step, and then separated by a C18 chromatographic column. 0.1% formic acid solution and acetonitrile were invoked as the aqueous phase and the organic phase for gradient elution, respectively. Electrospray positive voltage ionization and multi reaction monitoring （MRM） mode are used for compound detection, and matrix matching standard was used for quantification. Results: The analysis of aminophylline drugs was completed within 3.5 minutes, and the results showed good linear relationship （R＞0.998 0） on different matrices in the concentration range of 0.05~1.0 μg/mL. The average recoveries ranged from 87.2% to 101.3%, and the relative standard deviations ranged from 0.7% to 6.2% （n=6）. The detection limit was 2 μg/kg and the quantification limit was 5 μg/kg. Conclusion: The method which is simple and efficient, has good repeatability and high sensitivity. It is suitable for qualitative and quantitative analysis of aminophylline drug residues in edible tissues of pigs.

Carbon-based electrode as an economically benign choice is widely used in electrochemical or bio-electrochemical systems. However, its poor electrical conductivity that leading high overpotential and energy loss, especially in large scale facilities, remains a bottleneck for its application. Herein, a unique cross-stacking multi-layered reduced graphene oxide (rGO) and polyaniline (PANI) modified carbon brush is fabricated via one-step electro-depositing. In particular, the top-most layer of the modified electrode is orientated controlled to be rGO or PANI layer by adjusting the initial CV scanning in the positive or negative direction. As was indicated by cyclic voltammetry, the improved electrochemical activity is achieved by coupling the advantages of the highly conductive network offered by graphene with desirable stability provided by the well-dispersed deposition of nanoscale PANI particles. In comparison, the modified electrode with rGO on the top-most layer (LrGO) showed higher degree of sp2-hybridized -C-C- ordered structure in Raman profile, lower O/C ratio in XPS analysis, higher Zeta potential (−2.05 mV) and more hydrophilic than unmodified one. Moreover, benefiting from the unique cross-stacking multi-layered matrix of rGO and PANI, the best electrochemical performance was achieved on the electrode LrGO with high exerted electrochemical active surface area (ECSA) of 0.85 mF cm−2, and the charge transfer resistance as low as 0.32 Ω. The findings of this study provide a guidance for the modification and application of carbon-based electrode using rGO and PANI, which potentially enables the scaling-up of carbon-based electrode in various (bio-) electrochemical systems with high electrochemical performance.

Identifying and selecting high-quality seeds is crucial for improving crop yield. The purpose of this study was to improve the selection of crop seeds based on separating vital seeds from dead seeds, by predicting the potential germination ability of each seed, and thus improving seed quality. The methods of oxygen consumption (Q) of seeds and the headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) were evaluated for identifying the viability of individual seeds. Firstly, the oxygen consumption technique showed clear differences among the values related to respiratory characteristics for seeds that were either vital or not, and the discrimination ability of final oxygen consumption (Q120) was achieved not only in sweet corn seeds but also in pepper and wheat seeds. Besides, Qt was established as a new variable to shorten the measuring process in the Q2 (oxygen sensor) procedure, which was significantly related to the viability of individual seeds. To minimize seed damage during measurement, the timing for viability evaluation was pinpointed at the 12, 6 and 9 h for pepper, sweet corn, and wheat seeds based on the new variables concerning oxygen consumption (i.e., Q12, Q6 and Q9, respectively). The accuracies of viability prediction were 91.9, 97.7 and 96.2%, respectively. Dead seeds were identified and hence discarded, leading to an enhancement in the quality of the seed lot as indicated by an increase in germination percentage, from 86.6, 90.9, and 53.8% to all at 100%. We then used the HS-GC-IMS to determine the viability of individual sweet corn seeds, noting that corn seed has a heavier weight so the volatile gas components are more likely to be detected. A total of 48 chromatographic peaks were identified, among which 38 target compounds were characterized, including alcohols, aldehydes, acids and esters. However, there were no significant differences between the vital and dead seeds, due to the trace amount volatile composition differences among the individual seeds. Furthermore, a PCA based on the signal intensities of the target volatile compounds obtained was found to lose its effectiveness, as it was unable to distinguish those two types of sweet corn seeds. These strategies can provide a reference for the rapid detection of single seed viability.

Chirality characterizes an object that is not identical to its mirror image. In condensed matter physics, Fermions have been demonstrated to obtain chirality through structural and time-reversal symmetry breaking. These systems display unconventional electronic transport phenomena such as the quantum Hall effect and Weyl semimetals. However, for bosonic collective excitations in atomic lattices, chirality was only theoretically predicted and has never been observed. We experimentally show that phonons can exhibit intrinsic chirality in monolayer tungsten diselenide, whose lattice breaks the inversion symmetry and enables inequivalent electronic K and -K valley states. The time-reversal symmetry is also broken when we selectively excite the valley polarized holes by circularly polarized light. Brillouin-zone-boundary phonons are then optically created by the indirect infrared absorption through the hole-phonon interactions. The unidirectional intervalley transfer of holes ensures that only the phonon modes in one valley are excited. We found that such photons are chiral through the transient infrared circular dichroism, which proves the valley phonons responsible to the indirect absorption has non-zero pseudo-angular momentum. From the spectrum we further deduce the energy transferred to the phonons that agrees with both the first principle calculation and the double-resonance Raman spectroscopy. The chiral phonons have significant implications for electron-phonon coupling in solids, lattice-driven topological states, and energy efficient information processing.

Abstract Background This study aimed to evaluate the feasibility and safety of the trans-oral endoscopic thyroidectomy vestibular approach (TOETVA) with neuroprotection techniques for the surgical management of papillary thyroid carcinoma (PTC). Methods Patients with PTC who underwent TOETVA between December 2016 and July 2020 were included in this study, and their relevant clinical characteristics, operational details, and surgical outcomes were reviewed and extracted from their medical records for further analysis. Results A total of 75 patients successfully underwent TOETVA with zero conversions. Unilateral lobectomy with isthmectomy and total thyroidectomy were completed for 58 and 17 patients, respectively, all using our unique neuroprotective procedure and ipsilateral central neck dissection (CND). The mean number of retrieved lymph nodes versus positive lymph nodes was 6.8 ± 3.7 vs. 1.5 ± 2.3. Postoperative complications included three cases of transient superior laryngeal nerve (SLN) palsy (4.0%), five cases of transient recurrent laryngeal nerve (RLN) palsy (6.7%), 14 cases of transient hypoparathyroidism (18.7%), two cases of numb chin (2.7%) and two cases of flap perforation (2.7%). The follow-up period for patients with PTC lasted for 15.6 ± 10.9 months, during which no other complications or tumor recurrence were observed. Conclusion TOETVA can be safely performed for patients with PTC with satisfactory results during the short-term follow-up period. Our neuroprotection techniques can be integrated into TOETVA, which is worth recommending for PTC patients who desire better cosmetic surgical outcomes.

Chirality reveals symmetry breaking of the fundamental interaction of elementary particles. In condensed matter, for example, the chirality of electrons governs many unconventional transport phenomena such as the quantum Hall effect. Here we show that phonons can exhibit intrinsic chirality in monolayer tungsten diselenide. The broken inversion symmetry of the lattice lifts the degeneracy of clockwise and counterclockwise phonon modes at the corners of the Brillouin zone. We identified the phonons by the intervalley transfer of holes through hole-phonon interactions during the indirect infrared absorption, and we confirmed their chirality by the infrared circular dichroism arising from pseudoangular momentum conservation. The chiral phonons are important for electron-phonon coupling in solids, phonon-driven topological states, and energy-efficient information processing.

Abstract The design and production of active, durable, and nonprecious electrocatalysts toward alkaline hydrogen oxidation and evolution reactions (HOR/HER) are extremely appealing for the implementation of hydrogen economy, but remain challenging. Here, we report a facile electric shock synthesis of an efficient, stable, and inexpensive NiCoCuMoW multi‐element alloy on Ni foam (NiCoCuMoW) as a bifunctional electrocatalyst for both HOR and HER. For the HOR, the current density of NiCoCuMoW could reach ∼11.2 mA cm–2 when the overpotential is 100 mV, higher than that for commercial Pt/C (∼7.2 mA cm–2) and control alloy samples with less elements, along with superior CO tolerance. Moreover, for the HER, the overpotential at 10 mA cm−2 for NiCoCuMoW is only 21 mV, along with a Tafel slope of low to 63.7 mV dec−1, rivaling the commercial Pt/C as well (35 mV and 109.7 mV dec−1). Density functional theory calculations indicate that alloying Ni, Co, Cu, Mo, and W can tune the electronic structure of individual metals and provide multiple active sites to optimize the hydrogen and hydroxyl intermediates adsorption, collaboratively resulting in enhanced electrocatalytic activity.

Blast, a disease caused by Magnaporthe oryzae, is a major constraint for rice production worldwide. Introgression of durable blast resistance genes into high-yielding rice cultivars has been considered a priority to control the disease. The blast resistance Pik locus, located on chromosome 11, contains at least six important resistance genes, but these genes have not been widely employed in resistance breeding since existing markers hardly satisfy current breeding needs due to their limited scope of application. In this study, two PCR-based markers, Pikp-Del and Pi1-In, were developed to target the specific InDel (insertion/deletion) of the Pik-p and Pi-1 genes, respectively. The two markers precisely distinguished Pik-p, Pi-1, and the K-type alleles at the Pik locus, which is a necessary element for functional genes from rice varieties. Results also revealed that only several old varieties contain the two genes, of which nearly half carry the K-type alleles. Therefore, these identified varieties can serve as new gene sources for developing blast resistant rice. The two newly developed markers will be highly useful for the use of Pik-p, Pi-1 and other resistance genes at the Pik locus in marker-assisted selection (MAS) breeding programs.

The recent development of 2D monolayer lateral semiconductor has created new paradigm to develop p-n heterojunctions. Albeit, the growth methods of these heterostructures typically result in alloy structures at the interface, limiting the development for high-efficiency photovoltaic (PV) devices. Here, the PV properties of sequentially grown alloy-free 2D monolayer WSe2 -MoS2 lateral p-n heterojunction are explores. The PV devices show an extraordinary power conversion efficiency of 2.56% under AM 1.5G illumination. The large surface active area enables the full exposure of the depletion region, leading to excellent omnidirectional light harvesting characteristic with only 5% reduction of efficiency at incident angles up to 75°. Modeling studies demonstrate the PV devices comply with typical principles, increasing the feasibility for further development. Furthermore, the appropriate electrode-spacing design can lead to environment-independent PV properties. These robust PV properties deriving from the atomically sharp lateral p-n interface can help develop the next-generation photovoltaics.