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While LC display technologies have deep roots in augmented, virtual, and mixed realities, LC optics is emerging as a pivotal area within AR/VR/MR optics and the display community. [ABSTRACT FROM AUTHOR]

Polarization Volume Hologram (PVH) waveguide is an innovative liquid crystal‐based diffractive waveguide designed for augmented reality (AR) smart glasses, showcasing exceptional optical performance and simplified fabrication process. This presentation offers a comprehensive overview, including its working principles, advantages, performance optimization, process development, challenges and opportunities. The objective is to provide insights into PVH waveguide technology, from its inception to practical implementation. [ABSTRACT FROM AUTHOR]

Eye‐tracking is vital in AR/VR/MR systems for display correction, rendering, accommodation, and more. However, existing eye‐tracking solutions fall short in accuracy, efficiency, form factor, and population coverage. Using Liquid crystal polarization hologram (LCPH) for eye‐tracking purposes offers a compact form‐factor with excellent performance. [ABSTRACT FROM AUTHOR]

Relying on the Biomedical Big Data Center of West China Hospital, this paper makes an in-depth research on the construction method and application of breast cancer-specific database system based on full data lifecycle, including the establishment of data standards, data fusion and governance, multi-modal knowledge graph, data security sharing and value application of breast cancer-specific database. The research was developed by establishing the breast cancer master data and metadata standards, then collecting, mapping and governing the structured and unstructured clinical data, and parsing and processing the electronic medical records with NLP natural language processing method or other applicable methods, as well as constructing the breast cancer-specific database system to support the application of data in clinical practices, scientific research, and teaching in hospitals, giving full play to the value of medical big data of the Biomedical Big Data Center of West China Hospital.

The development of high‐performance X‐ray detectors requires scintillators with fast decay time, high light yield, stability, and X‐ray absorption capacity, which are difficult to achieve in a single material. Here, we present the first example of a lanthanide chalcogenide of LaCsSiS4 : 1 % Ce3+ that simultaneously integrates multiple desirable properties for an ideal scintillator. LaCsSiS4 : 1 % Ce3+ demonstrates a remarkably low detection limit of 43.13 nGyair s−1 and a high photoluminescence quantum yield of 98.24 %, resulting in a high light yield of 50480±1441 photons/MeV. Notably, LaCsSiS4 : 1 % Ce3+ exhibits a fast decay time of only 29.35±0.16 ns, making it one of the fastest scintillators among all lanthanide‐based inorganic scintillators. Furthermore, this material shows robust radiation and moisture resistance, endowing it with suitability for chemical processing under solution conditions. To demonstrate the X‐ray imaging capacity of LaCsSiS4 : 1 % Ce3+, we fabricated a flexible X‐ray detector that achieved a high spatial resolution of 8.2 lp mm−1. This work highlights the potential of lanthanide chalcogenide as a promising candidate for high‐performance scintillators. [ABSTRACT FROM AUTHOR]

Background: To combat/control the COVID-19 pandemic, a complete lockdown was implemented in China for almost 6 months during 2020. Purpose: To determine the impact of a long-term lockdown on the academic performance of first-year nursing students via mandatory online learning, and to determine the benefits of online teaching. Methods: The recruitment and academic performance of 1st-year nursing students were assessed between 2019 [prior to COVID-19, n = 195, (146 women)] and 2020 [during COVID-19, n = 180 (142 women)]. The independent sample t test or Mann-Whitney test was applied for a comparison between these two groups. Results: There was no significant difference in student recruitment between 2019 and 2020. The overall performance of the first-year students improved in the Biochemistry, Immunopathology, Traditional Chinese Medicine Nursing and Combined Nursing courses via mandatory online teaching in 2020 compared with traditional teaching in 2019. Conclusion: Suspension of in-class learning but continuing education virtually online has occurred without negatively impacting academic performance, thus academic goals are more than achievable in a complete lockdown situation. This study offers firm evidence to forge a path for developments in teaching methods to better incorporate virtual learning and technology in order to adapt to fast-changing environments. However, the psychological/psychiatric and physical impact of the COVID-19 lockdown and the lack of face-to-face interaction on these students remains to be explored. [ABSTRACT FROM AUTHOR]

Liquid crystal optics are highly favorable for AR/VR/MR near‐eye displays because of the capability of modulating polarization and phase in an ultra‐compact profile. In this presentation, we discuss state‐of‐the‐art LC polarization hologram solutions for AR/VR/MR display technical needs, followed by remaining challenges and opportunities in the way towards high‐image‐quality and all‐day‐wearable near‐eye displays. [ABSTRACT FROM AUTHOR]

Monoclinic α‐Ag2S is an intriguing member of transition metal sulfides with great potential for all‐inorganic flexible optoelectronics and thermoelectrics. Fabrication of large‐area, high‐quality α‐Ag2S thin films and understanding their charge transport properties are critical for device operations yet have remained largely unexplored. Here, a novel two‐step, the solution‐processed approach is reported to produce wafer‐sized, highly crystalline α‐Ag2S thin films. Ultrafast terahertz (THz) conductivity measurements reveal that photogenerated charge carriers undergo efficient band transport, with room‐temperature mobility of ≈150 cm2 V‐1 s‐1 and a diffusion length exceeding 500 nm. Furthermore, introducing poly(vinyl alcohol) (PVA) as the rigid component into the aqueous silver thiolate precursor enables the synthesis of free‐standing α‐Ag2S thin films with a mobility of ≈35 cm2 V‐1 s‐1, demonstrating their potential for flexible optoelectronics. This study provides a facile synthesis route for high‐quality, large‐area α‐Ag2S thin films with good charge transport properties, relevant for their integration into optoelectronics and wearable electronics. [ABSTRACT FROM AUTHOR]

A study was undertaken to identify differences in the performance of low-impact development (LID) measures in arid and humid cities. Yinchuan and Guangzhou in China were selected as a representative of each type. A stormwater management model was constructed with the aid of a geographic information system and LID measures of permeable pavements (PP), rain gardens (RG), green roofs (GR) and combinations of these were then designed. The results showed that a combination of PP, RG and GR provided the largest reduction in total runoff, peak runoff and runoff coefficient in both cities. Paired measures also delivered a significantly higher performance than single measures, with PP plus GR better than other paired combinations. The results of this work could guide the construction of sponge cities in both arid and humid areas. [ABSTRACT FROM AUTHOR]

Background. Cancer diagnosis entails substantial psychological distress and is associated with dramatically increased risks of suicidal behaviors. However, little is known about the suicide risk among cancer survivors who developed a second malignant neoplasm (SMN). Methods. Using the Surveillance, Epidemiology, and End Results database, we conducted a population-based cohort study involving 7,824,709 patients with first malignant neoplasm (FMN). We measured the hazard ratios (HRs) of suicide death after receiving a SMN diagnosis using Cox proportional hazard models, as compared with patients with FMN. The comparison with the US population was achieved by calculating standardized mortality ratios (SMRs). Results. Totally 685,727 FMN patients received a diagnosis of SMN during follow-up, and we in total identified 10,930 and 937 suicide deaths among FMN and SMN patients, respectively. The HR of suicide deaths was 1.23 (95% confidence interval (CI), 1.14–1.31) after a SMN diagnosis, compared with FMN patients, after adjusting for sociodemographic factors, tumor characteristics, and cancer treatment. As compared with the general population, while both SMN and FMN patients suffered an increased risk of suicide deaths, the excess risk was higher among SMN patients than FMN patients (age-, sex-, and calendar-year-adjusted SMR 1.65 (95% CI 1.54–1.75) vs. 1.29 (95% CI 1.26–1.31); P difference < 0.0001). Notably, across different time periods, we observed the greatest risk elevation during the first 3 months after a cancer diagnosis. Conclusions. Compared with either patients with FMN or the general population, cancer survivors who received a SMN diagnosis were at increased risk of suicide death. The risk elevation was most prominent soon after the cancer diagnosis, highlighting the necessity of providing timely psychological support to cancer survivors with a SMN. [ABSTRACT FROM AUTHOR]

Purpose: Through this nationwide survey on ACR BI-RADS including ultrasound images of 10 selected breast lesions, we aimed to learn about consistency in feature interpretation and assessment categories and to identify factors that might contribute to inconsistencies, thereby promoting the application of BI-RADS in China. Materials and Methods: The survey was delivered through a self-developed website about blinded image interpretation and was released to the public through online platforms and social media. A total of 10 representative lesions were selected by an experienced radiologist to gather information about the general practice of BI-RADS lexicons and categories. The Kappa statistic, the chi-squared test, and descriptive statistics were used for data analysis. Results: Nine hundred ultrasound workers completed the questionnaire, coming from all provinces and major cities in China. They had different positions, grades of work organization, and seniority. The interrater agreement of BI-RADS features was fair to substantial (kappa value: 0.37– 0.66). For BI-RADS categories, the highest agreement was observed in the typical benign group (average constituent rate = 74.78%), and generally lower agreement was observed in the typical malignant (average constituent rate = 36.03%) and suspicious groups (average constituent rate = 39.02%). Conclusion: We found inconsistencies in BI-RADS applications, providing direction for image feature research using big data. Therefore, we call for more efforts to improve the consistency of BI-RADS application and provide an evidence-based basis for identifying benign and malignant lesions by sonographic features. [ABSTRACT FROM AUTHOR]

We discovered that lamellar silver thiolates (Ag-MPA) possess reversible temperature dependent blue-to-near infrared optical transitions. Our analyses revealed that structural flexibility of Ag-MPA is responsible for the transitions. The polymer-like nature of Ag-MPA makes up-scaling the reaction feasible and allows for facile processing for applications ranging from bio-imaging to opto-electronics. [ABSTRACT FROM AUTHOR]

In this paper, we discuss different photo‐patterning paths for fabricating liquid crystal photonics devices, like geometric phase elements and polarization volume holograms for augmented reality and virtual reality (AR/VR) optical systems. We review the viability of typical photo‐patterning methods for small‐quantity research purposes, with a focus on direct write and interference recording. We present detailed comparisons between direct duplication and projection duplication, with recommendations for cost‐ and time‐efficient manufacturing paths. [ABSTRACT FROM AUTHOR]

Liquid crystal has been widely used in display applications, including Augmented Reality (AR) and Virtual Reality (VR) headset. In this paper, we discuss how liquid crystal technology can enable a virtual reality (VR) headset with glass‐type form factor, better image quality, and wearing comfort. [ABSTRACT FROM AUTHOR]

In this paper, a new steel-wood composite column with an H-shaped section was proposed. In order to form an H-shaped cross section, a larch board is fixed on the outer surface of the left and right edges of a hot-rolled H-beam by using physical connection. When the eccentricity is the same, eccentric compression tests were carried out on two types of columns by changing the thickness of the larch board, cross-sectional area of the hot-rolled H-beam, and slenderness ratio in composite columns. Therefore, type A is joined by structural glue only with the larch board and hot-rolled H-beam, and type B is joined by both structural glue and bolts. With the variation of strain and deflection, failure process and failure modes of the hot-rolled H-beam and larch from composite columns under various loads were observed, and the ultimate bearing capacity and stability of composite columns were studied. The test results showed that the overall working performance of the hot-rolled H-beam and larch board was good, and the stability of the hot-rolled H-beam column could be effectively improved. With the increase of wood thickness, cross-sectional area of the hot-rolled H-beam, slenderness ratio of composite columns, and the bearing capacity of the specimens were increased. Moreover, a simplified formula was proposed by the superposition principle. The theoretical analysis accorded with the experimental results, thus providing a reference basis for further study and application of similar steel-wood composite columns. [ABSTRACT FROM AUTHOR]