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Two-dimensional (2D) layered materials without centrosymmetry, such as GaSe, have emerged as promising novel optical materials due to large second-order nonlinear susceptibilities. However, their nonlinear responses are severely limited by the short interaction between the 2D materials and light, which should be improved by coupling them with photonic structures with strong field confinement. Here, we theoretically design photonic crystal circular Bragg gratings (CBG) based on hole gratings with a quality factor as high as Q = 8 × 103, a mode volume as small as V = 1.18 (λ/n)3, and vertical emission of light field in silicon nitride thin film platform. Experimentally, we achieved a Q value up to nearly 4 × 103, resulting in a 1,200-fold enhancement of second harmonic generation from GaSe flakes with a thickness of 50 nm coupling to the CBG structures under continuous-wave excitation. Our work endows silicon-based photonic platforms with significant second-order nonlinear effect, which is potentially applied in on-chip quantum light sources and nonlinear frequency conversion.

The Ili River Basin (IRB) is located in the northwest of China. With its large-scale zone and abundant resources, it is believed to be a "wet island" and a biotic resource storehouse in the dry regions of Eurasia. The IRB has stable ecological conditions and abundant water resources, providing natural conditions for agricultural production and human settlements. With the population increasing and economic development advancing, the competition for land resources is becoming fierce, leading to some ecological problems in this region. Therefore, understanding the spatiotemporal changes and driving mechanisms of the "three-zone space" (TZS) in the IRB is of significant practical importance for promoting sustainable development and optimizing the territorial spatial pattern. This study first analyzes the characteristics and intensity of the TZS changes from 2000 to 2020. Then, it utilizes the optimized parameter Geodetector (OPGD) to analyze the driving mechanisms behind these changes. The results show the following. Firstly, the agricultural space (AS) increased by a total of 837.5 km2, the urban space (US) increased by 519.64 km2, and other ecological space (OES) increased by 1518.83 km2. Green ecological space (GES) decreased by 2875.97 km2. Secondly, intensity analysis indicated that the total TZS change in IRB was 11.07%. At the spatial-type level, the increased intensities of OES, US, and AS were active. In spatial transformation intensity, US and OES tended to transform into AS; AS tended to transform into US; and OES and GES had a mutual transformation tendency. Thirdly, AS converted into US around emerging cities like Khorgas and Cocodala. The conversion towards GES was scattered. The mutual conversion between OES and GES showed spatial distribution consistency, mainly occurring in the Borohoro ranges and the Halik ranges. Lastly, regarding the driving mechanisms, the evolution of US in the IRB was driven by social and economic factors. Location and climate factors accelerated agricultural development, facilitating the transformation of GES and OES into AS. Climate and economic factors played a crucial role in the scale of conversions between OES and GES. The findings can provide a basis for the governance and protection of the IRB, help to form a rational territorial spatial pattern, and offer scientific guidance for sustainable land management. [ABSTRACT FROM AUTHOR]

Lithium niobate (LN), as a nonlinear material with a large nonlinear susceptibility, has been widely employed in second harmonic generation (SHG) up to ultraviolet (UV) frequency range due to its broad low-absorption window. In nanophotonics, it is possible to harness the Mie resonances associated with the single dielectric particles to boost the nonlinear light–matter interactions. Here, we fabricate single Mie-resonant LN nanospheres on a SiO2 substrate via the femtosecond (fs) laser ablation technique. By exploiting the magnetic dipole (MD) Mie resonance, UV SHG from the LN nanosphere is significantly enhanced with a measured conversion efficiency of 4.45 × 10−8 under the excitation of an fs laser at 750 nm. The single LN nanospheres achieved in this work could serve as Mie resonators for building nonlinear nanophotonic devices such as frequency converters and quantum light sources, etc.

Phytoremediation of heavy metal polluted soil has become an efficient and environment-friendly method. The main mechanisms of phytoremediation consist of phytoextraction, phytovolatilization phytostabilization, and phytotransformation. But there are some limitations in the actual remediation effect of plants enriching heavy metals. At present, a wealth of joint remediation methods have been carried out. This paper reviewed the phytoremediation mechanisms and the research status of phytoremediation, such as Cd, As and Pb, and put forward the research direction of phytoremediation and the combination with other technologies.

This paper addresses the joint selective maintenance and repairperson assignment problem (JSM–RAP) for complex multicomponent systems. The systems perform consecutive missions separated by scheduled finite duration breaks and are imperfectly maintained during the breaks. Current selective maintenance (SM) models usually assume that only one repair channel is available or that the repairperson assignment optimisation can be done at a subsequent stage. Using a generalised reliability function for k-out-of-n systems, we formulate the JSM–RAP for multicomponent systems more complex than the series-parallel systems commonly used in previous SM models. Two nonlinear formulations and their corresponding binary integer programming models are then proposed and optimally solved. Numerical experiments show the added value of the proposed approach and highlight the benefit of jointly carrying out the selection of the components to be maintained, the maintenance level to be performed and the assignment of the maintenance tasks to repairpersons. It is also shown that the flexibility provided by mixed skill cohorts of repairpersons over uniform cohorts can yield higher performance levels when the skillsets are significantly different. [ABSTRACT FROM AUTHOR]

Social sustainability is a major concern of planners and local officials when urban renewal projects are being conducted. Extreme individualism can potentially cause conflicts of interest, making urban renewal in Western cities fraught with various types of social risks. As a country with a deep-rooted socialist tradition, urban renewal projects in China are influenced by collectivist culture and show different features from those of the West. The objective of this research is to investigate how different stakeholders in urban redevelopment projects, including local residents, social organizations, the local state, and developers, interact with each other and how the associated social risks are hedged against. Using a recent well-known project in the city of Guangzhou, the authors attempt to present the latest progress in social risk management in China. With support from a government-sponsored project, the authors have conducted a questionnaire-based survey with a year-long fieldwork follow-up. Using ATLAS.ti software, we found that that "residents' demand", "status of collaboration", and "degree of trust" are the keys to risk management. The results of an ordered probit model show that residents are worried about overall planning, the relocation timetable, and whether their personal needs are taken into account. It is also indicated that the timely disclosure of project information, high-quality public participation, and a reasonable compensation plan can possibly boost the support rate. The authors suggest that utilizing China's collectivist culture could be an effective way to mitigate social risks, and residents' personal interests should also be respected. [ABSTRACT FROM AUTHOR]

BTK inhibitor (BTKi) Ibrutinib carries an increased bleeding risk compared to more selective BTKis Acalabrutinib and Zanubrutinib, however, its impact on vascular endothelium remains unknown. In this study, we found that Ibrutinib induced stronger cytotoxic effect on endothelial cells than Zanubrutinib, however, Acalabrutinib cytotoxicity was extremely weak. RNA-seq, followed by KEGG analysis and quantitative RT-PCR validation, was conducted to identify the differential apoptotic target genes of BTKis, leading to their distinct cytotoxic effects on endothelial cells, which showed that Ibrutinib and Zanubrutinib dramatically modulated the expression of critical apoptotic genes, GADD45B, FOS, and BCL2A1, among which FOS and GADD45B were upregulated more significantly by Ibrutinib than Zanubrutinib, however, Acalabrutinib downregulated BCL2A1 moderately and was not able to modulate the expression of FOS and GADD45B. Next, we performed in vitro angiogenesis assays and found that Ibrutinib was more able to induce endothelial dysfunction than Zanubrutinib via stimulating more BMP4 expression, however, Acalabrutinib had no such effect. Especially, the capacity of Ibrutinib to induce endothelial dysfunction can be antagonized by targeting BMP4. Accordingly, Ibrutinib, as an angiogenesis inhibitor, inhibited ovarian and breast cancer progression in vivo. Collectively, our findings addressed a novel molecular basis underlying Ibrutinib-induced endothelial cell dysfunction and suggested the potential application of Ibrutinib to treat angiogenesis-dependent cancers. [ABSTRACT FROM AUTHOR]

T cell immune protection plays a pivotal role in the treatment of patients with hematological malignancies. However, T cell exhaustion might lead to the possibility of immune escape of hematological malignancies. Adoptive cell therapy (ACT) with chimeric antigen receptor T (CAR-T) cells can restore the activity of exhausted T cell through reprogramming and is widely used in the treatment of relapsed/refractory (r/r) hematological malignancies. Of note, CD19, CD20, CD30, CD33, CD123, and CD269 as ideal targets have shown extraordinary potential for CAR-T cell therapy and other targets such as CD23 and SLAMF7 have brought promising future for clinical trials. However, CAR-T cells can also produce some adverse events after treatment of hematological malignancies, such as cytokine release syndrome (CRS), neurotoxicity, and on-target/off-tumor toxicity, which may cause systemic immune stress inflammation, destruction of the blood-brain barrier, and even normal tissue damage. In this review, we aim to summarize the composition of CAR-T cell and its application in the treatment of acute lymphocytic leukemia (ALL), chronic lymphocytic leukemia (CLL), non-Hodgkin's lymphoma (NHL), Hodgkin's lymphoma (HL), multiple myeloma (MM), and acute myeloid leukemia (AML). Moreover, we will review the disadvantages of CAR-T cell therapy and propose several comprehensive recommendations which might guide its development. [ABSTRACT FROM AUTHOR]

As the most common type of cancer in the world, hematological malignancies (HM) account for 10% of all annual cancer deaths and have attracted more attention. Conventional treatments, such as chemotherapy, radiotherapy, and hematopoietic stem cell transplantation (HSCT), could relieve patients suffering HM. However, serious side effects and high costs bring patients both physical complaints and mental pressure. Recently, compared with conventional therapeutic strategies for HM patients, antibody-based immunotherapies, including cancer vaccines, oncolytic virus therapies, monoclonal antibody treatments, and CAR-T cell therapies, have displayed longer survival time and fewer adverse reactions, even though specific efficacy and safety of these antibody-based immunotherapies still need to be evaluated and improved. This review summarized the advantages of antibody-based immunotherapies over conventional treatments, as well as its existing difficulties and solutions, thereby enhancing the understanding and applications of antibody-based immunotherapies in HM treatment. [ABSTRACT FROM AUTHOR]

Coherent light sources in silicon photonics are the long‐sought Holy Grail because silicon‐based materials have indirect bandgap. Traditional strategies for realizing such sources, e.g., heterogeneous photonic integration, strain engineering, and nonlinear process, are technologically demanding. Here, a hybrid lasing device composed of perovskite nanocrystals and silicon nitride nanobeam cavity is demonstrated. SiN photonic crystal naonobeam cavities are fabricated on a solid substrate with significantly improved thermal and mechanical stabilities compared to conventional suspended ones. In addition, adding a poly (methyl methacrylate) (PMMA)‐encapsulation layer on top of the SiN can significantly boost the Q‐factor of the cavity mode. By dispersing perovskite nanocrystals as emitters in the PMMA layer, high‐performance coherent emissions are obtained in terms of lasing threshold, linewidth, and mode volumes. The work offers a compelling way of creating solution‐processed active integrated photonic devices based on the mature platform of silicon photonics for applications in optical information science and photonic quantum technology. [ABSTRACT FROM AUTHOR]

Constructing 2 m-variable Boolean functions with optimal algebraic immunity based on decomposition of additive group of the finite field seems to be a promising approach since Tu and Deng's work. In this paper, we consider the same problem in a new way. Based on polar decomposition of the multiplicative group of , we propose a new construction of Boolean functions with optimal algebraic immunity. By a slight modification of it, we obtain a class of balanced Boolean functions achieving optimal algebraic immunity, which also have optimal algebraic degree and high nonlinearity. Computer investigations imply that this class of functions also behaves well against fast algebraic attacks. [ABSTRACT FROM AUTHOR]

Abstract: Laigle-Chapuy constructed a class of permutation polynomials over a finite field of characteristic 2, which includes several other known classes. In this paper, we determine the compositional inverses of all Laigle-Chapuyʼs permutation polynomials. Our method is based on a direct sum decomposition of the finite field. [Copyright &y& Elsevier]

Abstract: We give new characterizations of the algebra formed by all linearized polynomials reduced modulo over the finite field after briefly surveying some known ones. One isomorphism we construct is between and the composition algebra . The other isomorphism we construct is between and the so-called Dickson matrix algebra . We also further study the relations between a linearized polynomial and its associate Dickson matrix, generalizing a well-known criterion of Dickson on linearized permutation polynomials. Adjugate polynomial of a linearized polynomial is then introduced, and connections between them are discussed. Both of the new characterizations can bring us new approaches to establish some special forms of representations of linearized polynomials proposed recently by several authors. Structure of the subalgebra which is formed by all linearized polynomials reduced modulo over a subfield of where is also described. [Copyright &y& Elsevier]

Abstract: A marine bacteriophage infections model with stage structure is studied. Necessary and sufficient conditions for the extinction and permanence of the system are obtained, which enrich and improve the corresponding results given by S.A. Gourley and Y. Kuang [A delay reaction–diffusion model of the spread of bacteriophage infection, SIAM J. Appl. Math. 65 (2005) 550–566]. [Copyright &y& Elsevier]

In this paper, we study binomial skew polynomial rings A. We produce a Groebner basis of each two-sided ideal in A (as left ideal). Thus we give a positive answer to the question 2 in Gateva-Ivanova (Gateva-Ivanova, T. (1996). Skew polynomial rings with binomial relations. J. Algebra 185(3):710-753.): 'Is it true that A has a decidable membership problem for finitely generated two-sided ideals?' [ABSTRACT FROM AUTHOR]

Lead halide perovskite nanocrystals (NCs), especially the all-inorganic perovskite NCs, have drawn substantial attention for both fundamental research and device applications in recent years due to their unique optoelectronic properties. To build high-performance nanophotonic devices based on perovskite NCs, it is highly desirable to couple the NCs to photonic nanostructures for enhancing the radiative emission rate and improving the emission directionality of the NCs. In this work, we synthesized high-quality CsPbI3 NCs and further coupled them to dielectric circular Bragg gratings (CBGs). The efficient couplings between the perovskite NCs and the CBGs resulted in a 45.9-fold enhancement of the photoluminescence (PL) intensity and 3.2-fold acceleration of the radiative emission rate. Our work serves as an important step for building high-performance nanophotonic light emitting devices by integrating perovskite NCs with photonic nanostructures. [ABSTRACT FROM AUTHOR]