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Exciton-driven strong light–matter interactions in two-dimensional materials have displayed their advantages in applications in optoelectronics and photonics. However, the large exciton binding energy prohibits the efficient separation of photoexcited electron–hole pairs and is unfavorable for the application of photoelectrics and photovoltaics. Here, based on density-functional theory with the many-body perturbation method, we study the evolution of quasiparticle band structure, exciton, and optical properties with biaxial strain in 2D Hittorf's phosphorene. The pristine and +1% strained Hittorf's phosphorene are direct-band-gap semiconductors with the valence band maximal and the conduction band minimal located at the X point. When strain is approaching +2%, the conduction band minimal changes from the X point to the Γ point, resulting in a transition to the indirect band gap. This kind of indirect band gap persists to +5%. For the optical gap, we observe a modulation threshold of 0.33 eV over a +5% strain range. It is revealed that a p–n junction with efficient electron–hole excitation and separation is naturally formed in inhomogeneously strained 2D membrane. The transition from direct-band-gap to indirect-band-gap semiconductor, the strongly enhanced exciton lifetime, and the spatial separation of photoexcited electron–hole pairs under a moderate electric field will further inhibit the recombination. Together with the efficient visible light absorption which guarantees the absorption of solar spectra, these findings provide an effective avenue toward solar energy harvesting. [ABSTRACT FROM AUTHOR]

Assessing sampling biases caused by nonrandom specimen collecting is crucial in systematics, biogeography, and conservation. Nevertheless, research on the collecting biases of vascular plants in China remains limited. Here, we investigated the collecting status of gymnosperms in China using 48 673 herbarium specimens representing 180 Chinese gymnosperm species. The spatial and temporal patterns, collector and determiner biases, and phylogenetic and taxon biases were studied to comprehend the collecting bias of gymnosperms in China during 1900–2021. Meanwhile, we assessed the inventory completeness of gymnosperms to identify collecting hotspots and coldspots. The results showed that gymnosperms predominantly inhabit mountainous areas in China. The historical collecting of gymnosperms in China can be divided into two distinct stages with four peaks of collecting activities. The distribution of collected or identified specimens per individual displays significant skewness, and the collecting of gymnosperms has the issues of overcollecting or undersampling. Inventory completeness remains deficient, and collecting intensity is weak in both northern China and the range of 22°–25° N in the southern region (i.e., central Yunnan, southern Guangxi, and eastern Guangdong). Additionally, observation of the spatial distribution reveals both hotspots and coldspots scattered across mountain regions, lacking clustering. This study revealed a highly polarized collecting pattern for gymnosperms in China. Consequently, we recommend optimizing collecting measures, targeted specimen collecting, and continuous dynamic monitoring of gymnosperms in future collecting efforts. These recommendations hold relevance not only for gymnosperms in China but also for other land plants worldwide. [ABSTRACT FROM AUTHOR]

Privacy by design (PbD) has attracted considerable attention from researchers and information security experts due to its enormous potential for protecting private information and improving the privacy and security quality of information technology products. The adoption of PbD among information engineers is currently limited owing to its innovativeness and the distinctive traits of the information technology industry. Utilising the Technology Acceptance Model as a framework, this study innovatively explores the pivotal factors and mechanisms that influence information engineers' decision-making in the adoption of PbD from the viewpoint of the perceived work risk. In this empirical research, professional information engineers were invited to complete a questionnaire survey. After analysing the data using partial least squares structural equation modelling, the results reveal that information engineers' perceived work risk in PbD (PWRP) negatively affects their perceptions of the usefulness and ease of use of PbD. This negative perception subsequently reduces their intention to implement PbD (INTP) and adversely impacts their attitudes towards implementing PbD (ATTP). Furthermore, the study findings reveal that a positive ATTP among engineers boosts their INTP and positively influences their behaviours regarding information security. This study provides an in-depth examination of these findings and lays a solid theoretical groundwork for the further promotion and implementation of PbD in information technology enterprises. Moreover, the findings offer invaluable support for management decisions in both information technology companies and information security regulatory authorities, significantly contributing to the expansion and deepening of research in the field of PbD. [ABSTRACT FROM AUTHOR]

The observation of magnetic ordering in atomically thin CrI_{3} and Cr_{2}Ge_{2}Te_{6} monolayers has aroused intense interest in condensed-matter physics and material science. Studies of van de Waals two-dimensional (2D) magnetic materials are of both fundamental importance and application interest. In particular, exciton-enhanced magneto-optical properties revealed in CrI_{3} and CrBr_{3} monolayers have expanded the understanding of exciton physics in 2D materials. Unlike CrI_{3} and CrBr_{3}, with out-of-plane magnetization, CrSBr has an in-plane magnetic moment, therefore providing a good opportunity to study the magnetic linear dichroism and high-order magneto-optical effects. Here, based on the many-body perturbation method within density-functional theory, we have studied quasiparticle electronic structure, exciton, and optical properties in CrSBr monolayer. A strongly bounded exciton has been identified with the first bright exciton located at 1.35 eV, in good agreement with an experiment of photoluminescence [Wilson et al., Nat. Mater. 20, 1657 (2021)1476-112210.1038/s41563-021-01070-8]. Strong contrast in the optical absorption is found between the electric fields lying along the in-plane two orthogonal directions. In accordance with a typical and realistic experimental setup, we show that the rotation angle of linear polarized light, either reflected or transmitted, could be comparable with those revealed in black phosphorene. Such large linear dichroism arises mainly from the anisotropic in-plane crystal structure. The magnetic contribution from the off-diagonal component of dielectric function to the linear dichroism in CrSBr is negligible. Our findings not only have revealed the excitonic effect on the optical and magneto-optical properties in 2D ferromagnet CrSBr, but also have shown its potential applications in 2D optics and optoelectronics.

Plant intraspecific trait variation (ITV) including sex-dependent differences are matters of many ecological consequences, from individual to ecosystem, especially in endangered and rare species. Taxus fuana is an endangered dioecious species with small and isolated populations endemic to the Himalayas region. Little is known about its trait variation between sexes, and among populations. In this study, 18 leaf traits from 179 reproductive trees (males and females) along the altitude (2600-3200m a.s.l.) of the T. fuana populations distributed in Gyirong County, Tibet, China, were measured. ITV and sources of variation in leaf traits were assessed. The relationship between leaf traits of males and females and altitude was analyzed separately. Variations in leaf traits of T. fuana ranged from 3.1% to 24.2%, with the smallest in leaf carbon content and the largest in leaf thickness to area ratio. On average 78.13% of the variation in leaf traits was from within populations and 21.87% among populations. The trends in leaf width, leaf nitrogen to phosphorus ratio, leaf carbon to nitrogen ratio, leaf carbon isotope ratio, and leaf nitrogen isotope ratio in relation to altitude were the same for males and females. Leaf length to width ratio varied significantly with altitude only in males, while leaf phosphorus content, leaf nitrogen content, and leaf carbon to phosphorus ratio varied significantly with altitude only in females. The correlation coefficients of most leaf traits of females with altitude were larger than that of males. In the relationship between leaf traits, there was a high similarity among males and females, but the altitude accounted for more explanation in females than in males. Our results suggested that the variation in leaf traits of T. fuana was small and did not dominate the interspecific competition in the local communities. Adaptation to the altitude gradient of T. fuana might be through altering nutrient storage processes and water use efficiency. Adaptation of male and female T. fuana to environmental changes showed differences, where the males were more tolerant and the females responded greatly to altitude. The differences in adaptation strategies between male and female T. fuana may be detrimental to the maintenance of their populations.

Familial amyloid polyneuropathy, an autosomal-dominant disease due to mutations in the transthyretin gene, often affects the heart and liver, and is treated best with a combined heart–liver transplantation (CHLT). Although it remains an uncommonly performed procedure, the number of patients undergoing CHLT is increasing. Because of the complexity associated with dual pathophysiology, CHLT poses an extraordinary challenge for anesthesia management. Either both heart and liver transplantation are performed on cardiopulmonary bypass (CPB); or heart transplantation is performed on CPB, followed by liver transplantation with venovenous bypass. Recent reports suggested that liver transplantation can be performed without bypass using the inferior vena cava-sparing technique. However, both bypass and caval sparing technique have their own complications. Here, we present the anesthesia management in a case of sequential heart–liver transplantation using a routine caval cross-clamp technique without venovenous bypass. A 48-year-old man complaining of chest tightness, chest pain, and shortness of breath was diagnosed with amyloid cardiomyopathy. Cardiac ultrasonography revealed thickening of ventricular walls and left ventricular systolic insufficiency (ejection fraction decreased from 46% to ∼20% in 6 months), which was refractory to medical therapy. Symptoms occurred repeatedly. Therefore, CHLT was planned. Heart transplantation was performed smoothly under general anesthesia and standard CPB. His heart functioned well with dobutamine and epinephrine infusion. Subsequently, the patient was weaned from CPB. Liver transplantation was planned using the piggyback procedure with the caval sparing technique. However, upon caval clamping, unexpected blood loss occurred. Clamping of the caval was tested followed by cross-clamping. Norepinephrine, epinephrine, and dobutamine were administered. After the hepatic vein was anastomosed, the clamp was released and nitroglycerin was administered. Hemodynamics was stable, and the patient was discharged after 37 days of hospitalization. The case indicates that CHLT could be performed using caval clamp without venovenous bypass in selected patients.

Summary: In this work, broadband terahertz (THz) wave emissions have been detected from the trigonal layered PtBi2 on the excitation of the femtosecond laser pulses. Such THz generation is found to arise from the dominated linear photogalvanic effect, which is further discovered to strongly depend on the unique electronic structures of PtBi2. Furthermore, an effective nonlinear susceptibility of PtBi2 is also obtained and is nearly two orders of magnitude larger than that of the traditional nonlinear crystal for THz generation.

The data assimilation algorithm is a common algorithm in space weather research. In this paper, the time-frequency information in the dispersion spectrum of lightning whistlers received by the ZH-1 satellite is used as the observed value, and the international reference ionospheric model serves as the background model to construct the calculation model of the propagation time of lightning whistlers in the ionosphere. Kalman filtering is adopted to assimilate the electron density distribution along the propagation path of lightning whistlers. The results show that the situation where the electron density of the background model deviates greatly from the true value is significantly improved through data assimilation. The electron density after assimilation is in good agreement with the true value, which effectively helps realize the process of using observed values to correct the background value. On this basis, the influence of the frequency difference on the assimilation inversion effect is studied, and the results show that the assimilation effect is worse when the frequency difference between frequency points is less than 1 kHz.

Abstract Helicobacter pylori (H. pylori) is listed as a class I carcinogen in human gastric cancer; however, the underlying mechanisms are poorly understood. In this study, we identified Protogenin (PRTG) was upregulated in both gastric cancer tissues and H. pylori-infected tissues by analyzing dysregulated genes in TCGA and GEO databases. Importantly, upregulated PRTG predicted poor prognosis of gastric cancer patients and integrative analysis revealed that PRTG served as an oncogenic protein in gastric cancer and was required for H. pylori-mediated tumorigenic activities in in vitro cellular and in vivo tumor-bearing mouse models. Mechanistically, H. pylori infection enhanced PRTG expression by promoting transcriptional factor ZEB1 stabilization and recruitment to the PRTG promoter, and which then activated the sub-following cGMP/PKG signaling pathway in bioinformatic and cellular studies. Cellular studies further confirmed that PRTG depended on activating cGMP/PKG axis to promote proliferation, metastasis, and chemoresistance of gastric cancer cells. The PKG inhibitor KT5823 played synergistic anti-tumor effects with cisplatin and paclitaxel to gastric cancer cells in in vitro cellular and in vivo tumor-bearing mouse models. Taken together, our findings suggested that H. pylori infection depends on ZEB1 to induce PRTG upregulation, and which leading to the development and progression of gastric cancer through activating cGMP/PKG signaling pathway. Blocking PRTG/cGMP/PKG axis, therefore, presents a promising novel therapeutic strategy for gastric cancer.

Purpose: This paper develops a ‘light’ total productive maintenance (TPM) model suitable for small and medium-sized enterprises (SMEs). By design, the system is rudimentary, using a relatively small sum of capital investment and resources. The model recommends TPM implementation in three stages, namely plan, improve, and sustain. Design/methodology/approach: The literature review provides the inputs to the model development. Action research is used to demonstrate and verify the effectiveness and practicability of the framework, in an SME manufacturing hydraulic parts in China. Overall Equipment Effectiveness (OEE) and awareness of employees were studied before and after the implementation. Findings: The case study shows a significantly improved production efficiency of the equipment. The framework structuralizes TPM deployment and binding different levels of the organization into the program, from planning, implementation to sustaining the practices. To break the barrier of shop-floor resistance, the leader must drive many activities unassisted, it, therefore, necessitates an open endorsement of authority by the steering committee composed of top management. The Prudent pilot run of TPM helped to accelerate the implementation at critical equipment, in addition to cultivating experience and hence confidence among staff. Research limitations/implications: This study provides a pragmatic reference to other researchers and practitioners to promote a light TPM model in SMEs, without losing the essence of TPM. Being action research with the case study in a specific manufacturing industry, the resultant evidence, therefore, is anecdotal. Originality/value: The model adopts a phased method to implement TPM, without aggravating the financial and human resource burden of the enterprise. It promotes the cultivation of employees’ TPM awareness and active involvement, which can lay a solid foundation for the wide implementation of TPM in SMEs.

A new Sillago species, the black-banded sillago, Sillago nigrofasciata sp. nov., is described based on 302 specimens sampled from the southern coast of China. Morphological comparisons have been conducted between the new species and ten other Sillago species. The results show that the new species is characterized by a black mid-lateral band below the lateral line when fresh; other characteristics are similar to those of Sillago sihama but subtle differences exist on the swim bladder between Sillago nigrofasciata sp. nov. and S. sihama. A detailed description and illustrations are provided for the new species. The validity of this new species is also supported by a genetic comparison using sequences of the mitochondrial cytochrome c oxidase subunit I (COI) gene.

As a famous tonic herb, Cistanches Herba is known for its broad medicinal functions, especially its hormone balancing, anti-aging, anti-dementia, anti-tumor, anti-oxidative, neuroprotective, and hepatoprotective effects. This study aims to provide a comprehensive bibliometric analysis of studies on Cistanche and to identify research hotspots and frontier topics on the genus. Based on the metrological analysis software CiteSpace, 443 Cistanche related papers were quantitatively reviewed. The results indicate that 330 institutions from 46 countries have publications in this field. China was the leading country in terms of research importance and number of publication (335 articles). In the past decades, studies on Cistanche have mainly focused on its rich active substances and pharmacological effects. Although the research trend shows that Cistanche has grown from an endangered species to an important industrial plant, its breeding and cultivation continue to be important areas for research. In the future, the application of Cistanche species as functional foods may be a new research trend. In addition, active collaborations among researchers, institutions, and countries are expected.

The environmental awareness and concerns (plastic pollution) worldwide have driven the development of sustainable and environmentally friendly biopolymer derived from renewable materials. Biopolymers, especially L-lactic acid (L-LA) have played a crucial role in manufacturing polylactic acid, a biodegradable thermoplastic. Recently, L-LA production from non-edible macroalgal biomass has gained immense attraction due to it offers the simplest saccharification process for the biorefinery route. However, the commercialization of macroalgal-based L-LA is still limited due to high production costs. This paper has comprehensively reviewed the potential and development of third-generation feedstock for L-LA production, including significant technological barriers to be overcome for potential commercialization purposes. Then, an insight into the state-of-the-art hydrolysis and fermentation technologies using macroalgae as feedstock are also deliberated in detail. Furthermore, this review provides a conceivable picture of macroalgae-based L-LA biorefinery and future research directions that can be served as an important guideline for scientists, policymakers, and industrial players.