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Abstract: The paper reviews the motivation of the shift from form-focused methods to content-based instruction in ESL/EFL settings, and makes a survey of empirical researches about effects of the narrative approach on EFL/ESL learning in different parts of the world. All the researches listed in the paper suggest that the narrative approach is a desirable medium to facilitate learners’ language competence. Meanwhile the paper, considering the English teaching context in China, analyzes the constraints and challenges in applying the approach, and accordingly presents some suggestions and advice for EFL teachers and researchers in China [Copyright &y& Elsevier]

Objective: To present a case series of the exstrophy-epispadias complex (EEC) with isolated ectopic bowel segment (IEBS) with the literature review, highlighting the clinical findings and treatments.Materials and Methods: We present 3 cases of bladder exstrophy (BE) with IEBS in our institute and reviewed the literature in PubMed with the terms "("bladder exstrophy" OR "epispadias") AND ("visceral sequestration" OR "sequestered" OR "ectopic bowel")."Results: There were 2 males and 1 female. The IEBS was detected by physical examination in 2 cases and by ultrasonography in another one. All cases were BE accompanying with lower abdominal mass which adhered to the bladder wall but was separated from the digestive system. All cases underwent the IEBS excision and BE repair simultaneously. Pathological result of IEBS suggested the histological structures of colon. There were totally 13 cases of EEC with IEBS reported in the literature, including 2 (15%) epispadias, 9 (69%) covered BE, 1 (8%) duplicate BE and 1 (8%) classic bladder exstrophy. Although their clinical manifestations were various, IEBS excision were safely conducted in all cases.Conclusion: EEC with IEBS is an extremely rare congenital malformation. Physical and imaging examinations are important for diagnoses. Surgical excision is safe and effective for managing IEBS. [ABSTRACT FROM AUTHOR]

The burgeoning need for extensive data processing has sparked enthusiasm for the development of a novel optical logic gate platform. In this study, junction field-effect phototransistors based on molybdenum disulfide/Germanium (MoS 2 /Ge) heterojunctions are constructed as optical logic units. This device demonstrates a positive photoresponse that is attributed to the photoconductivity effect occurring upon irradiation with visible (Vis) light. Under the illumination of near-infrared (NIR) optics with wavelengths within the communication band, the device shows a negative photoresponse, which is associated with the interlayer Coulomb interactions. The current state of the device can be effectively modulated as different logical states by precisely tuning the wavelength and power density of the optical. Within a 3 × 3 MoS 2 /Ge phototransistor array, five essentially all-optical logic gates ("AND," "OR," "NAND," "NOT," and "NOR") can be achieved in every signal unit. Furthermore, three complex all-optical logical operations are demonstrated by integrating two MoS 2 /Ge phototransistors in series. Compared to electronic designs, these all-optical logic devices offer a significant reduction in transistor number, with savings of 50-94% when implementing the above-mentioned functions. These results present opportunities for the development of photonic chips with low power consumption, high fidelity, and large volumes., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

We propose an infrared-sensitive negative differential transconductance (NDT) phototransistor based on a graphene/WS 2 /Au double junction with a SiO 2 /Ge gate. By changing the drain bias, diverse field-effect characteristics can be achieved. Typical p-type and n-type behavior is obtained under negative and positive drain bias, respectively. And NDT behavior is observed in the transfer curves under positive drain bias. It is believed to originate from competition between the top and bottom channel currents in stepped layers of WS 2 at different gate voltages. Moreover, this phototransistor shows a gate-modulated rectification ratio of 0.03 to 88.3. In optoelectronic experiments, the phototransistor exhibits a responsivity of 2.76 A/W under visible light at 532 nm. By contrast, an interesting negative responsivity of -29.5 µA/W is obtained and the NDT vanishes under illumination by infrared light at 1550 nm. A complementary inverter based on two proposed devices of the same structure is constructed. The maximum voltage gain of the complementary inverter reaches 0.79 at a supply voltage of 1.5 V. These results demonstrate a new method of realizing next-generation two- and three-dimensional electronic and optoelectronic multifunctional devices.

An artificial retina system shows a promising potential to achieve fast response, low power consumption, and high integration density for vision sensing systems. Optoelectronic sensors, which can emulate the neurobiological functionalities of retinal neurons, are crucial in the artificial retina systems. Here, we propose a WSe 2 phototransistor with asymmetrical van der Waals (vdWs) stacking that can be used as an optoelectronic sensor in artificial retina systems. Through the utilization of the gate-tunable self-powered bidirectional photoresponse of this phototransistor, the neurobiological functionalities of both bipolar cells and cone cells, as well as the hierarchical connectivity between these two types of retinal neurons, are successfully mimicked by a single device. This self-powered bidirectional photoresponse is attributed to the asymmetrical vdWs stacking structure, which enables the transition from an n-p to p + -p homojunction in the WSe 2 channel under different polarities of gate bias. Moreover, the detectivity and ON/OFF ratio of this phototransistor reach as high as 1.8 × 10 13 Jones and 5.3 × 10 4 , respectively, and a rise/fall time <80 μs is achieved, as well, which reveals good photodetection performance. The proof of this device provides a pathway for the future development of neuromorphic vision devices and systems.

The two-dimensional/three-dimensional van der Waals heterostructures provide novel optoelectronic properties for the next-generation of information devices. Herein, MoS 2 /Ge heterojunction avalanche photodetectors are readily obtained. The device with an Ag electrode at MoS 2 side exhibits more stable rectification characteristics than that with an Au electrode. The rectification radio greater than 10 3 and a significant avalanche breakdown are observed in the device. The responsivity of 170 and 4 A/W and the maximum gain of 320 and 13 are obtained under 532 and 1550 nm illumination, respectively. Such photoelectric properties are attributed to the carrier multiplication at a Ge/MoS 2 junction due to an avalanche breakdown. The mechanism is confirmed by the Sentaurus TCAD-simulated I-V characteristics.

A Ge metal-semiconductor-metal photodetector covered with asymmetric H f S e 2 contact geometries has been proposed to realize high-performance unbiased photodetection at 1550 nm. At -1 V bias, the responsivity of this device shows a 71% improvement compared to the device without H f S e 2 . Moreover, the responsivity and detectivity of this device at zero bias can reach to 71.2 mA/W and 3.27×10 10 Jones, respectively. Furthermore, the fall time of this device is 2.2 µs and 53% shorter than the device without H f S e 2 . This work provides a feasible way to develop unbiased Ge-based photodetectors in the near-IR communications band.

Here, SiGeSn nanostructures were grown via molecular beam epitaxy on a Si (111) substrate with the assistance of Sn droplets. Owing to the thermal effect and the compressive strain induced by a lattice mismatch, Si and Sn atoms were successfully incorporated into the Ge matrix during the Sn-guided Ge deposition process. A low growth temperature of 350 °C produced a variety of SiGeSn nanostructures of different sizes, attributed to the variation of the initial Sn droplet size. Using energy-dispersive X-ray spectroscopy, the Sn, Si and Ge contents of a defect-free SiGeSn nanoisland were approximately determined to be 0.05, 0.09 and 0.86, respectively. Furthermore, as the growth temperature increased past 600 °C, the growth direction of the nanostructure was changed thermally from out-of-plane to in-plane. Meanwhile, the stacked SiGeSn nanowires grown along the 〈112〉 direction remained defect-free, though some threading dislocations were observed in the smooth SiGeSn nanowires along the 〈110〉 direction. These results offer a novel method to grow Si-based SiGeSn nanostructures while possessing important implications for fabricating further optoelectronic devices., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Self-assembled Mn 0.06 Ge 0.94 quantum dots (QDs) on a Si substrate or Ge x Si 1-x virtual substrate (VS) were grown by molecular beam epitaxy. The Ge x Si 1-x VS of different thicknesses and Ge compositions x were utilized to modulate the ferromagnetic properties of the above QDs. The MnGe QDs on Ge x Si 1-x VS show a significantly enhanced ferromagnetism with a Curie temperature above 220 K. On the basis of the microstructural and magnetization results, the ferromagnetic properties of the QDs on Ge x Si 1-x VS are believed to come from the intrinsic MnGe ferromagnetic phase rather than any intermetallic ferromagnetic compounds of Mn and Ge. At the same time, we found that by increasing the Ge composition x of Ge x Si 1-x VS, the ferromagnetism of QDs grown on VS will markedly increase due to the improvements of hole concentration and Ge composition inside the QDs. These results are fundamentally important in the understanding and especially in the realization of high Curie temperature MnGe diluted magnetic semiconductors.

In this paper, a high-quality sputtered-GeSn layer on Ge (100) with a Sn composition up to 7% was demonstrated. The crystallinity of the GeSn layer was investigated via high-resolution X-ray diffraction (HR-XRD) and the strain relaxation degree of the GeSn layer was evaluated to be approximately 50%. A novel method was also proposed to evaluate the averaged threading dislocation densities (TDDs) in the GeSn layer, which was obtained from the rocking curve of GeSn layer along the (004) plane. The photoluminescence (PL) measurement result shows the significant optical emission (1870 nm) from the deposited high-quality GeSn layer. To verify whether our deposited GeSn can be used for optoelectronic devices, we fabricated the simple vertical p-i-n diode, and the room temperature current-voltage (I-V) characteristic was obtained. Our work paves the way for future sputtered-GeSn optimization, which is critical for optoelectronic applications., Competing Interests: The authors declare no conflicts of interest

Purpose: Comparison of topical vs general aneasthesia for strabismus surgery., Methods: Preoperative patients (aged 6～12 years) were divided into two study groups: the topical aneasthesia group (n=22), and the general aneasthesia group (n=21). The study groups were compared on the following measures: analgesic effect, surgical correction effect, eye-heart reflex, preoperative preparation time and operation time, using t-tests or X2 tests where appropriate., Results: Compared with the general aneasthesia group, the topical aneasthesia group gained better surgical correction results (P<0.05), had a lower rate of eye-heart reflex (P<0.05), and had a shorter preoperative preparation time (P<0.001). No significant difference was observed between the groups in terms of the analgesic effect or operation time (P>0.05)., Conclusion: Topical aneasthesia represents a safe and effective alternative to general aneasthesia for strabismus surgery in children.