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Polarized photodetectors have been widely used in military and civilian applications. The investigation of promising two-dimensional materials with low symmetry structures will be of great significance for the development of polarized integrated nanodevices. In this work, chromium thiophosphate (CrPS4), a ternary layered semiconductor with low symmetry puckered structures and unique linear dichroism (LD) conversion behavior is introduced to act as a polarization-sensitive photodetector. Angle-resolved polarized Raman spectra (ARPRS), polarization-resolved photoluminescence (PL) spectra, polarization-resolved absorption spectroscopy (PRAS), and electrical transport measurement systematically indicate intriguing anisotropic optical and electrical properties in 2D (two-dimensional) CrPS4. The photodetector of CrPS4 shows a linear anisotropy ratio of ≈1.33 with 405 nm illumination. This pioneering research not only stimulates interest in the development of novel anisotropic 2D materials but also enriches the family of polarization-sensitive photodetectors. [ABSTRACT FROM AUTHOR]

PdSe2, a star photosensitive functional material, has been successfully used in photodetectors based on sensing mechanisms of photogating, photoconductive, and photovoltaic effects. Here, a photothermoelectric (PTE) effect is observed in photodetectors based on PdSe2 flakes grown by chemical vapor deposition. The unique photoresponse arises from an electron temperature gradient instead of electron–hole separation. Direct evidence of the PTE effect is confirmed by a nonlocal photoresponse under zero bias. Moreover, the PdSe2 photodetector shows high performance in terms of ultrafast response speed (4 µs), high air‐stability, broadband spectrum photodetection, reasonable responsivity, and anisotropic optical response. This study paves a new way for developing high‐performance photodetectors based on PdSe2 layered materials. [ABSTRACT FROM AUTHOR]

Photodetectors based on two-dimensional (2D) materials have great potential applications in the field of new energy, such as fuel cells, solar cells, and other fields. Van der Waals (vdW) heterojunction photodiodes are expected to be one of the promising applications of two-dimensional materials due to the photoelectric properties without consideration of lattice mismatch. High-efficiency photoelectric sensors based on two-dimensional materials have great significance to reducing the energy consumption of devices. Here, we build a complex vdW heterostructure by combining InS0.3Se0.7 with another suitable 2D material WS2. Few-layer graphite was used as electrodes to enhance the optoelectronic performance of indium monochalcogenides. Evident photocurrent is observed in the InS0.3Se0.7/WS2 vdW heterostructure device arising from the formed p–n junction at the interface. The uniformity and photoresponse of the InS0.3Se0.7/WS2 vdW heterostructure has been further investigated by the photocurrent mapping. It shows that the entire photovoltaic current was originated from the InS0.3Se0.7/WS2 vdW heterojunction by scanning photocurrent microscope images. Furthermore, the response speed is enhanced at small bias voltage. The transient photoresponse can be well reproduced in almost 100 cycles, indicating the good repeatable optoelectronic performance. Our study indicates that the as-prepared InS0.3Se0.7/WS2 vdW heterostructures are attractive building blocks for photodetectors application. Our findings will open up a new way to further develop high-performance, low-power, and energy-efficient photodetectors based on indium monochalcogenides. [ABSTRACT FROM AUTHOR]

Neuropathic pain (NP) is caused by a lesion or disease of the somatosensory system and is characterized by abnormal hypersensitivity to stimuli and nociceptive responses to non-noxious stimuli, affecting approximately 7-10% of the general population. However, current first-line drugs like non-steroidal anti-inflammatory agents and opioids have limitations, including dose-limiting side effects, dependence, and tolerability issues. Therefore, developing new interventions for the management of NP is urgent. In this study, we discovered that the high-frequency terahertz stimulation (HFTS) at approximately 36 THz effectively alleviates NP symptoms in mice with spared nerve injury. Computational simulation suggests that the frequency resonates with the carbonyl group in the filter region of Kv1.2 channels, facilitating the translocation of potassium ions. In vivo and in vitro results demonstrate that HFTS reduces the excitability of pyramidal neurons in the anterior cingulate cortex likely through enhancing the voltage-gated K + and also the leak K + conductance. This research presents a novel optical intervention strategy with terahertz waves for the treatment of NP and holds promising applications in other nervous system diseases., Competing Interests: WP, PW, CT, HZ, KC, HS, YT, AL, ZZ, YY, KW, CC, YW, TC No competing interests declared, (© 2024, Peng, Wang, Tan et al.)

ρ-Hydroxyacetophenone is an important and versatile compound that has been widely used in medicine, cosmetics, new materials, and other fields. At present, there are two ways to obtain ρ-hydroxyacetophenone. One is to extract it from plants, such as Artemisia capillaris Thunb and Cynanchum otophyllum Schneid, and the other is to synthesize it by using chemical methods. Of these two methods, the second is the main one, although it has problems, such as flammable and explosive reagents, difficult separation of by-products, and harsh reaction conditions. To solve these issues, we adopted genetic engineering in this study to construct engineered Escherichia coli containing Hped gene or EbA309 gene. Whole-cell biotransformation was conducted under the same conditions to select the engineered E. coli with the higher activity. Orthogonal tests were conducted to determine the optimal biotransformation condition of the engineered E. coli . The results showed that the optimal condition was as follows: substrate concentration of 40 mmol/l, IPTG concentration of 0.1 mmol/l, an induction temperature of 25°C, and a transformation temperature of 35°C. Under this condition, the effects of transformation time on the ρ-hydroxyacetophenone concentration and cell growth were further studied. We found that as the transformation time extended, the ρ-hydroxyacetophenone concentration showed a gradually increasing trend. However, when the ρ-hydroxyacetophenone concentration increased to 1583.19 ± 44.34 mg/l in 24 h, cell growth was inhibited and then entered a plateau. In this research, we realized the synthesis of ρ-hydroxyacetophenone by biotransformation, and our findings lay a preliminary foundation for further improving and developing this method.

Recent advances in two-dimensional (2D) materials play an essential role in boosting modern electronics and optoelectronics. Thus far, transition metal dichalcogenides (TMDs) as emerging members of 2D materials, and the van der Waals heterostructures (vdWHs) based on TMDs have been extensively investigated owing to their prominent capabilities and unique crystal structures. In this work, an original vdWH composed of molybdenum disulfide (MoS 2 ) and platinum disulfide (PtS 2 ) was comprehensively studied as a field-effect transistor (FET) and photodetector. A gate-tunable rectifying behavior was obtained, stemming from the band design of PtS 2 /MoS 2 vdWH. Upon 685 nm laser illumination, it also exhibited a superior photodetection performance with a distinctly high photoresponsivity of 403 A W -1 , a comparable detectivity of 1.07 × 10 11 Jones, and an excellent external quantum efficiency of 7.32 × 10 4 %. More importantly, fast rise (24 ms) and decay (21 ms) times were obtained under 685 nm light illumination attributed to the unilateral depletion region structure. Further, the photovoltaic effect and photocurrent of the heterojunction could be modulated by a back gate voltage. All these results indicated that such 2D-TMD-based vdWHs provide a new idea for realizing high-performance electronic and optoelectronic devices.

van der Waals (vdW) heterodiodes composed of two-dimensional (2D) layered materials led to a new prospect in photoelectron diodes and photovoltaic devices. Existing studies have shown that Type-I heterostructures have great potential to be used as photodetectors; however, the tunneling phenomena in Type-I heterostructures have not been fully revealed. Herein, a highly efficient nn + WS 2 /PtS 2 Type-I vdW heterostructure photodiode is constructed. The device shows an ultrahigh reverse rectification ratio of 10 5 owing to the transmission barrier-induced low reverse current. A unilateral depletion region is formed on WS 2 , which inhibits the recombination of carriers at the interface and makes the external quantum efficiency (EQE) of the device reach 67%. Due to the tunneling mechanism of the device, which allows the co-existence of a large photocurrent and a low dark current, this device achieves a light on/off ratio of over 10 5 . In addition, this band design allows the device to maintain a high detectivity of 4.53 × 10 10 Jones. Our work provides some new ideas for exploring new high-efficiency photodiodes.

Broken-gap van der Waals (vdW) heterojunctions based on 2D materials are promising structures to fabricate high-speed switching and low-power multifunctional devices thanks to its charge transport versus quantum tunneling mechanism. However, the tunneling current is usually generated under both positive and negative bias voltage, resulting in small rectification and photocurrent on/off ratio. In this paper, we report a broken-gap vdW heterojunction PtS 2 /WSe 2 with a bilateral accumulation region design and a big band offset by utilizing thick PtS 2 as an effective carrier-selective contact, which exhibits an ultrahigh reverser rectification ratio approaching 10 8 and on/off ratio over 10 8 at room temperature. We also find excellent photodetection properties in such a heterodiode with a large photocurrent on/off ratio over 10 5 due to its ultralow forward current and a comparable photodetectivity of 3.8 × 10 10 Jones. In addition, the response time of such a photodetector reaches 8 μs owing to the photoinduced tunneling mechanism and reduced interface trapping effect. The proposed heterojunction not only demonstrates the high-performance broken-gap heterodiode but also provides in-depth understanding of the tunneling mechanism in the development of future electronic and optoelectronic applications.

Lateral homojunctions made of two-dimensional (2D) layered materials are promising for optoelectronic and electronic applications. Here, we report the lateral WSe 2 -WSe 2 homojunction photodiodes formed spontaneously by thickness modulation in which there are unique band structures of a unilateral depletion region. The electrically tunable junctions can be switched from n-n to p-p diodes, and the corresponding rectification ratio increases from about 1 to 1.2 × 10 4 . In addition, an obvious photovoltaic behavior is observed at zero gate voltage, which exhibits a large open voltage of 0.49 V and a short-circuit current of 0.125 nA under visible light irradiation. In addition, due to the unilateral depletion region, the diode can achieve a high detectivity of 4.4 × 10 10 Jones and a fast photoresponse speed of 0.18 ms at V g = 0 and V ds = 0. The studies not only demonstrated the great potential of the lateral homojunction photodiodes for a self-power photodetector but also allowed for the development of other functional devices, such as a nonvolatile programmable diode for logic rectifiers.

Objective To investigate the effect of candesartan on angiotensin II (Ang II)-induced proliferation and migration of vascular smooth muscle cells and its effect on connexin 43 (Cx43). Methods A7r5 cells were cultured in vitro and randomly divided into control group, AngII group and AngII combined with candesartan group. Cell viability was detected by CCK-8 assay; the migration and invasion ability of A7r5 cells were measured by wound-healing and Transwell TM assay; the expression and distribution of Cx43 on A7r5 cells were detected by immunofluorescence assay. Cx43, osteopontin (OPN), proliferating cell nuclear antigen (PCNA), p-MEK1/2 and p-ERK1/2 protein levels of A7r5 cells were detected by Western blot analysis. Results Compared with the control group, the AngII group had higher cell proliferation and migration ability, and the AngII combined with candesartan group had a lower concentration than the AngII group. Cx43 was expressed in the A7r5 cell membrane and nuclear membrane. The expression of Cx43 were enhanced in the AngII group than in the control group, and the expressions of Cx43, OPN, PCNA, p-MEK1/2 and p-ERK1/2 significantly increased compared with AngII. The expression of protein significantly decreased in AngII combined with candesartan group. Conclusion Candesartan can reduce the proliferation and migration of smooth muscle cells induced by AngII, and its mechanism may be related to Cx43 and MEK/ERK signaling pathways.