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Anisotropic optical crystals can exhibit a hyperbolic response within the Reststrahlen band (RB) and support directional polaritonic propagations when interacting with light. Most of the reported low-symmetry optical crystals showcase the evolution from hyperbolic to elliptic dispersion topologies, largely owing to their adjacent RBs being either overlapped or separated. Here, we report an exceptional Reststrahlen point (ERP) in rare-earth oxyorthosilicate Y2SiO5, at which two neighboring RBs almost kiss each other. Consequently, we observe the direct hyperbolic-to-hyperbolic topological transition: the hyperbolic branches close and reopen along with the rotating transverse axis (TA). At such ERP, the TA merges to the direction orthogonal to its proximate phonon mode, mainly due to the interplay between these two non-orthogonal phonon modes. We also find that even with the existence of only one single RB, the TA can rotate in-plane. Our findings are prevalent in isostructural rare-earth oxyorthosilicates, such as Lu2SiO5. The universally underlying physics of ERP and its corresponding special class of rare-earth oxyorthosilicates may offer playgrounds for continuously tuning phonon polariton propagation direction, and broadband controlling light dispersion of polaritonic nanodevices. The authors reveal hyperbolic-to-hyperbolic transitions where two nearby Reststrahlen bands just touch each other. Such phenomena are prevalent in isostructural rare-earth oxyorthosilicates and unfolds vast opportunities for broadband on-chip light control. [ABSTRACT FROM AUTHOR]

Although retraction is widely perceived as stigmatic in the scientific community, little is known about how retraction stigma is communicated via retraction notices. Drawing on a dataset of 1,000 retraction notices, this study investigated what communication strategies were employed in retraction notices to construct and manage retraction stigma and whether retraction notices penned by journal authorities and authors of retracted publications differed in the use of those strategies. A content analysis of the retraction notices identified three types of retraction stigma construction strategy (i.e., creating marks, assigning responsibility, and exposing perils) and four types of retraction stigma management strategy (i.e., concealing stigma visibility, refraining from labelling, manipulating responsibility assignment, and offering correction and remediation). Authorship-based differences were found in the deployment of all seven types of stigma construction and management strategy and 17 individual strategies. The use of two types of construction strategy were significantly associated with the use of three types of management strategy. These findings revealed retraction notices as capable of both stigmatizing and destigmatizing. Thus, retraction notices constitute a discourse genre that is imbued with communicative tensions rooted in the diverse functions that they can serve. [ABSTRACT FROM AUTHOR]

Linguistic expressions of confusion, namely confusion markers, construe discrepancies between an academic author's prior knowledge and the information received. These emotive responses motivate knowledge-seeking behaviors to dissolve cognitive incongruities and are inherently connected with knowledge-making. Limited research has, however, examined how they partake in knowledge construction and dissemination in academic writing. Drawing on a frame-based analytical approach, this study investigated how an academic author's disciplinary background and time of publication may mediate the use of confusion markers in 640 research articles sampled from four disciplines. The corpus-based analyses were complemented by insights from 16 specialists to explore how considerations underlying their use of confusion markers shaped their academic writing. The findings indicated that the overall use of confusion markers changed over time and that disciplinary background and time of publication were significant predictors of several frame elements. The observed disciplinary and diachronic patterns of use can be explained in terms of epistemological orientations, developments in the academic world such as increasing disciplinary specialization and growing interdisciplinary research leading to a broadening of readership, and stiff competition in scholarly publication. [ABSTRACT FROM AUTHOR]

High-throughput super-resolution (SR) imaging is attractive for rapid and high-precision profiling in a wide range of biomedical applications. However, current SR methods require sophisticated acquisition optics and long integration times to acquire a single field of view. By exploiting the natural photophysics of fluorescence, fluctuation-based microscopy techniques can routinely break the diffraction limit without requiring additional optical components. However, their long acquisition time still poses a challenge for high-throughput imaging and the visualization of transient cellular dynamics. Here we propose super-resolution imaging based on autocorrelation with two-step deconvolution (SACD). Our method notably reduces the number of frames required by maximizing the detectable fluorescence fluctuation behaviour in each measurement. SACD requires only 20 frames to achieve a twofold improvement in lateral and axial resolution, whereas current SR optical fluctuation imaging (SOFI) needs more than 1,000 frames. With an acquisition time of ~10 min, we record SR images with 128-nm resolution over a field of view of 2.0 mm × 1.4 mm, which includes more than 2,000 cells. By applying the continuity and sparsity joint constraint, sparse deconvolution-assisted SACD enables four-dimensional imaging of live cells and events such as mitochondrial fission and fusion. Overall, as an open-sourced module, we anticipate that SACD will improve accessibility to SR imaging, thus facilitating biological studies of cells and organisms with high throughput and low cost. Super-resolution imaging based on autocorrelation with two-step deconvolution (SACD) enables recording super-resolution images with 128-nm spatial resolution over a field of view of 2.0 mm × 1.4 mm within a 10-min acquisition time. [ABSTRACT FROM AUTHOR]

Academic journal publications may be retracted following institutional investigations that confirm allegations of research misconduct. Retraction notices can provide insight into the role institutional investigations play in the decision to retract a publication. Through a content analysis of 7,318 retraction notices published between 1927 and 2019 and indexed by the Web of Science, we found that most retraction notices (73.7%) provided no information about institutional investigations that may have led to retractions. A minority of the retraction notices (26.3%) mentioned an institutional investigation either by journal authorities (12.1%), research performing organizations (10.3%), joint institutions (1.9%), research integrity and ethics governing bodies (1.0%), third-party institutions (0.5%), unspecified institutions (0.4%), or research funding organizations (0.1%). Comparing retraction notices issued before and after the introduction of retraction guidelines by the Committee on Publication Ethics (COPE) in 2009 revealed that those published after the guidelines’ publication were more likely to report investigations by journal authorities. Comparing retraction notices from different disciplines revealed that those from social sciences and the humanities were more likely to disclose investigations by research performing organizations than those from biomedical and natural sciences. Based on these findings, we suggest that the COPE retraction guidelines in the future make it mandatory to disclose in retraction notices institutional investigations leading to retractions. [ABSTRACT FROM AUTHOR]

Photonic crystals (PhCs) are a kind of artificial structures that can mold the flow of light at will. Polaritonic crystals (PoCs) made from polaritonic media offer a promising route to controlling nano-light at the subwavelength scale. Conventional bulk PhCs and recent van der Waals PoCs mainly show highly symmetric excitation of Bloch modes that closely rely on lattice orders. Here, we experimentally demonstrate a type of hyperbolic PoCs with configurable and low-symmetry deep-subwavelength Bloch modes that are robust against lattice rearrangement in certain directions. This is achieved by periodically perforating a natural crystal α-MoO3 that hosts in-plane hyperbolic phonon polaritons. The mode excitation and symmetry are controlled by the momentum matching between reciprocal lattice vectors and hyperbolic dispersions. We show that the Bloch modes and Bragg resonances of hyperbolic PoCs can be tuned through lattice scales and orientations while exhibiting robust properties immune to lattice rearrangement in the hyperbolic forbidden directions. Our findings provide insights into the physics of hyperbolic PoCs and expand the categories of PhCs, with potential applications in waveguiding, energy transfer, biosensing and quantum nano-optics. Photonic crystals (PhCs) are artificial periodic materials that can be used to manipulate the flow of light. Here, the authors report the realization of asymmetric PhCs based on in-plane hyperbolic phonon polaritons in perforated α-MoO3, showing low-symmetry deep-subwavelength Bloch modes that are robust against lattice rearrangement in specific directions. [ABSTRACT FROM AUTHOR]

This special issue sets out to revisit major bilingual and multilingual education policy and planning issues in key cities across the dynamic Greater Bay Area (GBA) of China (including Guangdong, Hong Kong, and Macau), as informed by the emerging insights from translanguaging theory (Li in Appl Linguist 39(1):9–30, 2018). Specifically, contributions are invited from the GBA and beyond to trace the milestone developments of relevant language policy and planning (LPP) initiatives featuring governmental policies on the language of instruction (e.g., English as Medium of Instruction, Chinese as Medium of Instruction) and the daily use of multiple linguistic resources or repertoires (e.g., language learner's L1 or mother tongue) in foreign/second language classrooms and/or in content-based classroom instruction. As such, major papers in the special issue not only set out to provide historical and analytical reviews of these related LPP issues across Hong Kong, Macau, and Guangdong Province but also reflect upon the language use and behaviors of the residents, showcasing their identity and attitudes and ideological stance toward the multiple languages that are being taught or used in daily life. Toward the end, we outline our research agendas for future endeavors in broader domains in the GBA and beyond through the translanguaging analytical tools. Overall, our position is that the GBA presents itself as an evolving, complex, and superdiverse zone of "Translanguaging Spaces" within which key LPP issues may need to be reconceptualized and implemented in such a way so as to fully reflect the dynamic and fluid multilingual, multicultural, and multisemiotic lived reality of the residents in this megapolis region. [ABSTRACT FROM AUTHOR]

Retraction of published research is laudable as a post-publication self-correction of science but undesirable as an indicator of grave violations of research and publication ethics. Given its various adverse consequences, retraction has a stigmatizing effect both in and beyond the academic community. However, little theoretical attention has been paid to the stigmatizing nature of retraction. Drawing on stigma theories and informed by research on retraction, we advance a conceptualization of retraction as stigma. We define retraction stigma as a discrediting evaluation of the professional competence and academic ethics of the entities held accountable for retraction. Accordingly, we identify seven core dimensions of retraction stigma, consider its functional justifications at both social and psychological levels, and distinguish its various targets and stakeholders. In view of the central role of retraction notices, we also discuss how retraction stigma is communicated via retraction notices and how authors of retraction notices may exercise their retraction stigma power and manipulate the stigmatizing force of retraction notices. We conclude by recommending retraction stigma as a theoretical framework for future research on retraction and pointing out several directions that this research can take. [ABSTRACT FROM AUTHOR]

Polaritons enable subwavelength confinement and highly anisotropic flows of light over a wide spectral range, holding the promise for applications in modern nanophotonic and optoelectronic devices. However, to fully realize their practical application potential, facile methods enabling nanoscale active control of polaritons are needed. Here, we introduce a hybrid polaritonic-oxide heterostructure platform consisting of van der Waals crystals, such as hexagonal boron nitride (hBN) or alpha-phase molybdenum trioxide (α-MoO3), transferred on nanoscale oxygen vacancy patterns on the surface of prototypical correlated perovskite oxide, samarium nickel oxide, SmNiO3 (SNO). Using a combination of scanning probe microscopy and infrared nanoimaging techniques, we demonstrate nanoscale reconfigurability of complex hyperbolic phonon polaritons patterned at the nanoscale with high resolution. Hydrogenation and temperature modulation allow spatially localized conductivity modulation of SNO nanoscale patterns, enabling robust real-time modulation and nanoscale reconfiguration of hyperbolic polaritons. Our work paves the way towards nanoscale programmable metasurface engineering for reconfigurable nanophotonic applications. Phonon polaritons in anisotropic van der Waals materials enable subwavelength confinement and controllable flow of light at the nanoscale. Here, the authors exploit correlated perovskite oxide (SmNiO3) substrates with tunable conductivity to obtain real-time modulation and nanoscale reconfiguration of hyperbolic polaritons in hBN and α-MoO3 crystals. [ABSTRACT FROM AUTHOR]

Optical metasurfaces with high quality factors (Q-factors) of chiral resonances can boost substantially light-matter interaction for various applications of chiral response in ultrathin, active, and nonlinear metadevices. However, current approaches lack the flexibility to enhance and tune the chirality and Q-factor simultaneously. Here, we suggest a design of chiral metasurface supporting bound state in the continuum (BIC) and demonstrate experimentally chiroptical responses with ultra-high Q-factors and near-perfect circular dichroism (CD = 0.93) at optical frequencies. We employ the symmetry-reduced meta-atoms with high birefringence supporting winding elliptical eigenstate polarizations with opposite helicity. It provides a convenient way for achieving the maximal planar chirality tuned by either breaking in-plane structure symmetry or changing illumination angle. Beyond linear CD, we also achieved strong near-field enhancement CD and near-unitary nonlinear CD in the same planar chiral metasurface design with circular eigen-polarization. Sharply resonant chirality realized in planar metasurfaces promises various practical applications including chiral lasers and chiral nonlinear filters. Here, the authors employ the physics of chiral bound states in the continuum and suggest planar chiral metasurfaces with simultaneous ultrahigh quality factor and near-perfect circular dichroism in both linear regime and nonlinear regime. [ABSTRACT FROM AUTHOR]

Computational meta-optics brings a twist on the accelerating hardware with the benefits of ultrafast speed, ultra-low power consumption, and parallel information processing in versatile applications. Recent advent of metasurfaces have enabled the full manipulation of electromagnetic waves within subwavelength scales, promising the multifunctional, high-throughput, compact and flat optical processors. In this trend, metasurfaces with nonlocality or multi-layer structures are proposed to perform analog optical computations based on Green's function or Fourier transform, intrinsically constrained by limited operations or large footprints/volume. Here, we showcase a Fourier-based metaprocessor to impart customized highly flexible transfer functions for analog computing upon our single-layer Huygens' metasurface. Basic mathematical operations, including differentiation and cross-correlation, are performed by directly modulating complex wavefronts in spatial Fourier domain, facilitating edge detection and pattern recognition of various image processing. Our work substantiates an ultracompact and powerful kernel processor, which could find important applications for optical analog computing and image processing. Here, the authors propose a Fourier-based metaprocessor to impart customized highly flexible transfer functions for analog computing. Differentiation and cross-correlation are performed to substantiate the ultracompact and high-throughput kernel processor. [ABSTRACT FROM AUTHOR]

Exceptional points (EPs) are degeneracies at which two or more eigenvalues and eigenstates of a physical system coalesce. Dynamically encircling EPs by varying the parameters of a non-Hermitian system enables chiral mode switching, that is, the final state of the system upon a closed loop in parameter space depends on the encircling handedness. In conventional schemes, the parametric evolution during the encircling process has to be sufficiently slow to ensure adiabaticity. Here, we show that fast parametric evolution along the parameter space boundary of the system Hamiltonian can relax this constraint. The proposed scheme enables highly efficient transmission and more compact footprint for asymmetric mode converters. We experimentally demonstrate these principles in a 57 μm-long double-coupled silicon waveguide system, enabling chiral mode switching with near-unity transmission efficiency at 1550 nm. This demonstration paves the way towards high-efficiency and highly integrated chiral mode switching for a wide range of practical applications. Chiral mode converters are found in a wide range of practical applications in optics, but the previous proposals suffer from low efficiency and large device size. Here the authors propose a highly efficient and compact chiral mode converter based on encircling exceptional points along Hamiltonian parameter space boundary, relaxing the adiabaticity constraints. [ABSTRACT FROM AUTHOR]

The lattice symmetry of a crystal is one of the most important factors in determining its physical properties. Particularly, low-symmetry crystals offer powerful opportunities to control light propagation, polarization and phase1–4. Materials featuring extreme optical anisotropy can support a hyperbolic response, enabling coupled light–matter interactions, also known as polaritons, with highly directional propagation and compression of light to deeply sub-wavelength scales5. Here we show that monoclinic crystals can support hyperbolic shear polaritons, a new polariton class arising in the mid-infrared to far-infrared due to shear phenomena in the dielectric response. This feature emerges in materials in which the dielectric tensor cannot be diagonalized, that is, in low-symmetry monoclinic and triclinic crystals in which several oscillators with non-orthogonal relative orientations contribute to the optical response6,7. Hyperbolic shear polaritons complement previous observations of hyperbolic phonon polaritons in orthorhombic1,3,4 and hexagonal8,9 crystal systems, unveiling new features, such as the continuous evolution of their propagation direction with frequency, tilted wavefronts and asymmetric responses. The interplay between diagonal loss and off-diagonal shear phenomena in the dielectric response of these materials has implications for new forms of non-Hermitian and topological photonic states. We anticipate that our results will motivate new directions for polariton physics in low-symmetry materials, which include geological minerals10, many common oxides11 and organic crystals12, greatly expanding the material base and extending design opportunities for compact photonic devices.Shear phenomena in the infrared dielectric response of a monoclinic crystal are shown to unveil a new polariton class termed hyperbolic shear polariton that can emerge in any low-symmetry monoclinic or triclinic system. [ABSTRACT FROM AUTHOR]

Let λ π (1 , ... , 1 , n) be the normalized Fourier coefficients of an even Hecke–Maass form π for S L (m , Z) with m ≥ 3 , and r 3 (n) = # { (n 1 , n 2 , n 3) ∈ Z 3 : n = n 1 2 + n 2 2 + n 3 2 } . In this paper, we introduce a refined version of the circle method to derive a sharp bound for the shifted convolution sum of GL(m) Fourier coefficients λ π (1 , ... , 1 , n) and r 3 (n) , which improves previous results (even under the generalized Ramanujan conjecture). [ABSTRACT FROM AUTHOR]

Polaritons are hybrid excitations of matter and photons. In recent years, polaritons in van der Waals nanomaterials—known as van der Waals polaritons—have shown great promise to guide the flow of light at the nanoscale over spectral regions ranging from the visible to the terahertz. A vibrant research field based on manipulating strong light–matter interactions in the form of polaritons, supported by these atomically thin van der Waals nanomaterials, is emerging for advanced nanophotonic and opto-electronic applications. Here we provide an overview of the state of the art of exploiting interface optics—such as refractive optics, meta-optics and moiré engineering—for the control of van der Waals polaritons. This enhanced control over van der Waals polaritons at the nanoscale has not only unveiled many new phenomena, but has also inspired valuable applications—including new avenues for nano-imaging, sensing, on-chip optical circuitry, and potentially many others in the years to come.This Review discusses the state of the art of interface optics—including refractive optics, meta-optics and moiré engineering—for the control of van der Waals polaritons. [ABSTRACT FROM AUTHOR]

Blockchain technologies have become increasingly popular and attracted great interest in recent years. Beyond the financial sector, blockchain technologies are promising for addressing the current limitations in food supply chain management. As blockchain adoption for food supply chains is still in an early stage, it is significant to have a thematic framework to systematically understand the processes, benefits, and challenges. This paper aims to explore the adoption of blockchain technologies in food supply chains with a thematic analysis. Desktop research is conducted, and data is collected from online databases, including news article (e.g. Factiva) and research paper databases (e.g. Web of Science). Then we carry out a qualitative thematic analysis, according to the investigation processes suggested by Creswell. Based on the thematic analysis, we identify seven first-order themes and two second-order themes in adoption processes; thirteen first-order themes, sixteen second-order themes, and five third-order themes in benefits; and fourteen first-order themes and five second-order themes in challenges. In addition, we discuss and propose how to improve blockchain adoption in food supply chains in practice. [ABSTRACT FROM AUTHOR]

Polaritons in anisotropic materials result in exotic optical features, which can provide opportunities to control light at the nanoscale1–10. So far these polaritons have been limited to two classes: bulk polaritons, which propagate inside a material, and surface polaritons, which decay exponentially away from an interface. Here we report a near-field observation of ghost phonon polaritons, which propagate with in-plane hyperbolic dispersion on the surface of a polar uniaxial crystal and, at the same time, exhibit oblique wavefronts in the bulk. Ghost polaritons are an atypical non-uniform surface wave solution of Maxwell’s equations, arising at the surface of uniaxial materials in which the optic axis is slanted with respect to the interface. They exhibit an unusual bi-state nature, being both propagating (phase-progressing) and evanescent (decaying) within the crystal bulk, in contrast to conventional surface waves that are purely evanescent away from the interface. Our real-space near-field imaging experiments reveal long-distance (over 20 micrometres), ray-like propagation of deeply subwavelength ghost polaritons across the surface, verifying long-range, directional and diffraction-less polariton propagation. At the same time, we show that control of the out-of-plane angle of the optic axis enables hyperbolic-to-elliptic topological transitions at fixed frequency, providing a route to tailor the band diagram topology of surface polariton waves. Our results demonstrate a polaritonic wave phenomenon with unique opportunities to tailor nanoscale light in natural anisotropic crystals.Hyperbolic phonon polaritons that exhibit long-distance, ray-like propagation and oblique wavefronts are described at the surface of an anisotropic bulk crystal. [ABSTRACT FROM AUTHOR]

In this paper, we apply the circle method to study the average behavior of the triple divisor function over values of quadratic form n 1 2 + n 2 2 + ⋯ + n l 2 with l ⩾ 3. We improve and generalize previous results. [ABSTRACT FROM AUTHOR]

In this paper, we study the shifted convolution sums of the Fourier coefficients λ π (1 , ... , 1 , n) and r s , k (n) with k ≥ 3 , where r s , k (n) denotes the number of representations of the positive integer n as sums of skth powers. We are able to generalize or improve previous results. [ABSTRACT FROM AUTHOR]

On the basis of transcriptome sequences, the fatty acid-binding protein (FABP) gene of Exopalaemon carinicauda was obtained by rapid amplification of cDNA ends (RACE) and named FABP. The full length of the FABP gene is 878 bp, with the open reading frame being 399 bp and the non-coding regions of the 5′ end and the 3′ end being 94 bp and 385 bp, respectively. The gene encodes a protein composed of 132 amino acids. A homology analysis showed that the FABP gene has high similarity with fatty acid-binding protein and retinoic acid-binding protein genes. Real-time PCR showed that the FABP gene was expressed mainly in subepidermal adipose tissue, and secondarily in intestine and heart. The expression characteristics at different developmental stages showed that the expression of the gene was low at the larval stage (0–25 d) and reached the highest level after 30 days. RNA interference results showed no significant difference in the appearance of E. carinicauda and no individual death after this gene was silenced. Compared with the control group, except C20:2n-6 which increased, the contents of the other 12 fatty acids in shrimps in the RNA interference group decreased significantly, and the total amount of fatty acids also decreased significantly, which suggests that the FABP gene is closely related to changes in fatty acid content in shrimp. [ABSTRACT FROM AUTHOR]

Polaritons – coupled excitations of photons and dipolar matter excitations – can propagate along anisotropic metasurfaces with either hyperbolic or elliptical dispersion. At the transition from hyperbolic to elliptical dispersion (corresponding to a topological transition), various intriguing phenomena are found, such as an enhancement of the photonic density of states, polariton canalization and hyperlensing. Here, we investigate theoretically and experimentally the topological transition, the polaritonic coupling and the strong nonlocal response in a uniaxial infrared-phononic metasurface, a grating of hexagonal boron nitride (hBN) nanoribbons. By hyperspectral infrared nanoimaging, we observe a synthetic transverse optical phonon resonance (strong collective near-field coupling of the nanoribbons) in the middle of the hBN Reststrahlen band, yielding a topological transition from hyperbolic to elliptical dispersion. We further visualize and characterize the spatial evolution of a deeply subwavelength canalization mode near the transition frequency, which is a collimated polariton that is the basis for hyperlensing and diffraction-less propagation. Phenomena such as polariton canalization and hyperlensing can be found at the transition from hyperbolic to elliptical dispersion. Here, the authors investigate this transition using hyperspectral infrared nanoimaging of polaritons in a grating of hexagonal boron nitride nanoribbons. [ABSTRACT FROM AUTHOR]

Twisted two-dimensional bilayer materials exhibit many exotic electronic phenomena. Manipulating the ‘twist angle’ between the two layers enables fine control of the electronic band structure, resulting in magic-angle flat-band superconductivity1,2, the formation of moiré excitons3–8 and interlayer magnetism9. However, there are limited demonstrations of such concepts for photons. Here we show how analogous principles, combined with extreme anisotropy, enable control and manipulation of the photonic dispersion of phonon polaritons in van der Waals bilayers. We experimentally observe tunable topological transitions from open (hyperbolic) to closed (elliptical) dispersion contours in bilayers of α-phase molybdenum trioxide (α-MoO3), arising when the rotation between the layers is at a photonic magic twist angle. These transitions are induced by polariton hybridization and are controlled by a topological quantity. At the transitions the bilayer dispersion flattens, exhibiting low-loss tunable polariton canalization and diffractionless propagation with a resolution of less than λ0/40, where λ0 is the free-space wavelength. Our findings extend twistronics10 and moiré physics to nanophotonics and polaritonics, with potential applications in nanoimaging, nanoscale light propagation, energy transfer and quantum physics.The photonic dispersion of phonon polaritons in bilayers of α-phase molybdenum trioxide can undergo tunable topological transitions at magic interlayer twist angles. [ABSTRACT FROM AUTHOR]

Lipocalin is a large family with complex functions including retinol-binding protein (RBP), crustacyanin (CRCN), apolipoprotein D, etc. In shrimps, it is well known that CRCN is related to body color. Recently, retinoic acid/retinol-binding protein was found in shrimp. However, little is known about the function of RBP and relationships among the gene members of lipocalin in shrimps. Based on the transcriptome sequences responding to starvation stress, three genes of the lipocalin–retinol-binding protein-like gene family (lipocalin-1, lipocalin-2, and lipocalin-3) were cloned by RACE from the ridgetail white prawn, Exopalaemon carinicauda. Homology analysis showed that these three genes had high similarity with the known insect apolipoprotein D gene and vertebrate retinol-binding protein gene, and they are of the same type in terms of evolution. Fluorescence quantitative PCR showed that the above three genes were mainly expressed in the ventral nerve cord of E. carinicauda. The expression characteristics of the three genes at different developmental stages showed that they were more highly expressed at the larval stage, which suggests that they might be related to embryonic and larval development. The RNA interference tests showed that after silencing lipocalin-1 and lipocalin-3, the body color of individual shrimps turned slightly red and the blue pigment in the epidermis largely disappeared, but no significant change took place in the appearance of individuals after silencing lipocalin-2. In addition, on the 6th and 16th days of interference, dead shrimps appeared in the lipocalin-1 and lipocalin-3 interference groups. The dead shrimps had hard crusts and remained in a molting posture. Totally, this study showed that the retinol-binding protein-like gene obtained in this study had certain biological functions in the growth and development and body color formation as CRCN; in addition, it also plays a role in nerve system and molting of E. carinicauda. [ABSTRACT FROM AUTHOR]

Let K3 be a non-normal cubic extension over ℚ:We study the higher moment of the coefficients of Dedekind zeta function over sum of two squares where 2 ⩽ l ⩽ 8 and n1; n2; l∈ ℤ. [ABSTRACT FROM AUTHOR]

Two-dimensional transition metal dichalcogenides (TMDCs) present extraordinary nonlinearities and direct bandgaps at the K and K′ valleys. These valleys can be optically manipulated through, for example, plasmon–valley-exciton coupling with spin-dependent photoluminescence. However, the weak coherence between the pumping and emission makes exploring nonlinear valleytronic devices based on TMDCs challenging. Here, we show that a synthetic metasurface, which entangles the phase and spin of light, can simultaneously enhance and manipulate nonlinear valley-locked chiral emission in monolayer tungsten disulfide (WS2) at room temperature. The second-harmonic valley photons, accessed and coherently pumped by light, with a spin-related geometric phase imparted by a gold (Au) metasurface, are separated and routed to predetermined directions in free space. In addition, the nonlinear photons with the same spin as the incident light are steered owing to the critical spin–valley-locked nonlinear selection rule of WS2 in our designed metasurface. Our synthetic TMDC–metasurface interface may facilitate advanced room-temperature and free-space nonlinear, quantum and valleytronic nanodevices. By entangling the phase and spin of light, a synthetic metasurface is shown to be able to coherently manipulate the valley-exciton-locked chiral emission in monolayer tungsten disulfide at room temperature. The findings will be of benefit to advanced room-temperature and free-space nonlinear, quantum and valleytronic nanodevices. [ABSTRACT FROM AUTHOR]

This study investigated the concurrent contributions of three components of metalinguistic awareness (i.e., phonological awareness, morphological awareness, and syntactic awareness) to the writing competence of primary three English-Chinese bilingual children in Singapore (n = 390) and monolingual Chinese-speaking children in Mainland China (n = 190). Hierarchical regression analyses found that the three components of metalinguistic awareness differed in their contributions to writing competence across the languages and between the two groups of children, with morphological awareness and syntactic awareness explaining markedly more variance than phonological awareness. Furthermore, SEM results revealed a robust cross-linguistic association between English and Chinese metalinguistic awareness in the bilingual children, which appeared to jointly undergird and support writing competence in both languages. Finally, home language use significantly predicted not only the bilingual children’s English metalinguistic awareness but also their writing performance in Chinese. These findings lend support to Cummins’s Common Underlying Proficiency and Developmental Interdependence Hypotheses, and underscore the importance of language context, formal instruction, and language features in children’s literacy development. [ABSTRACT FROM AUTHOR]

Letter to the Editor [ABSTRACT FROM AUTHOR]

Although Chinese university students' perceptions of plagiarism have been extensively investigated, those of their teachers have been surprisingly under-researched. This study sought to address this gap by investigating 112 Chinese university English teachers' knowledge of and attitudes towards plagiarism. While 57 participating teachers had overseas academic experience, the remaining ones received all their education in mainland China. They completed a perceptions of plagiarism survey that elicited their knowledge of several common forms of plagiarism in Anglo-American academia, perceptions of various possible causes of plagiarism, and attitudes towards plagiarism induced by different causes and plagiarism in general. The study found that the teachers reported varying knowledge of different types of transgressive textual practices, variegated perceptions of the different causes of plagiarism, but clearly punitive attitudes towards plagiarism. It also revealed significant differences between teachers with and without overseas academic experience in knowledge of and stances on plagiarism. These findings highlight the complexity of plagiarism as an intertextual phenomenon and point to the important role of cultural practices and academic socialisation in shaping perceptions of it. [ABSTRACT FROM AUTHOR]

This article reports on a questionnaire-based investigation of writing strategies used by Singapore primary school pupils. A sample of 1,618 pupils from two local primary schools participated in the study. A number of one-way ANOVA analyses were run to measure the relationship between the participants' use of writing strategies and their English language proficiency. The findings show that Singapore upper primary school pupils used a wide range of writing strategies at a medium frequency. Planning, text-generating, revising, monitoring and evaluating, and resourcing strategies were found to be significantly correlated with the participants' English language results. However, local variations were also detected. Methodological limitations and recommendations for future research are then discussed. [ABSTRACT FROM AUTHOR]

With the relentless internationalization and marketization of higher education in the past decades, English has been increasingly adopted as a medium of instruction at universities across the world. Recent research, however, has shown that despite its various optimistically envisioned goals, English-medium instruction (EMI) is not without problems in practice. This article reports a case study of an EMI Business Administration program for undergraduate students at a major university of finance and economy in mainland China. Informed by Spolsky's language policy framework, the study made a critical analysis of national/institutional policy statements and interviews with professors and students to uncover EMI-related language ideologies, language practices, and language management mechanisms. Findings evinced a complex interplay of these three constitutive components of language policy in the focal EMI program and revealed considerable misalignment between policy intentions and actual practices in the classroom. These findings raise concerns about the quality and consequences of EMI in Chinese higher education. The article concludes with recommendations for further research on EMI policies and practices in China. [ABSTRACT FROM AUTHOR]

This article reports a case study of an undergraduate English-medium program at a major university in mainland China. The study critically examines the language ideology, language management, and language practices revolving around the focal program. The data sources included national and institutional policy documents related to English-medium instruction and interviews with both professors and students in the English-medium program and its parallel Chinese-medium program. Drawing upon Spolsky's language policy framework for 'sensitizing concepts', qualitative analyses of the data revealed gaps between policy rhetoric and ground-level reality in the implementation of the focal program. Notably, institutional measures intended to enhance the quality of English-medium instruction were found to function as gate-keepers of access to English and potential benefits accruing from English proficiency. These findings add to our understanding of how medium-of-instruction policies in higher education are complicit in perpetuating and accentuating inequalities in Chinese society. [ABSTRACT FROM AUTHOR]

This article reports a case study of two Chinese-English bilingual families in Singapore and illustrates the importance of incorporating two hitherto disconnected fields of research-family language policy and family literacy practices-to an understanding of early language and literacy acquisition in the familial milieu. Specifically, this work illuminates how such language socialization processes as prolepsis, syncretism, and synergy mediate the influences of the larger sociocultural context on the focal children's bilingual and biliteracy learning at home. A comparison of the two families reveals similarities and differences in the way they drew on language practices from multiple resources to involve their children in an array of bilingual/biliteracy activities and to align these activities to the current and projected future needs of the children. The study shows how the family members' cultural backgrounds, past experiences of learning and parenting, educational beliefs, and aspirations for the children shaped language ideology, language practices, and language management at home. [ABSTRACT FROM AUTHOR]

Highly confined and low-loss polaritons are known to propagate isotropically over graphene and hexagonal boron nitride in the plane, leaving limited degrees of freedom in manipulating light at the nanoscale. The emerging family of biaxial van der Waals materials, such as α-MoO3 and V2O5, support exotic polariton propagation, as their auxiliary optical axis is in the plane. Here, exploiting this strong in-plane anisotropy, we report edge-tailored hyperbolic polaritons in patterned α-MoO3 nanocavities via real-space nanoimaging. We find that the angle between the edge orientation and the crystallographic direction significantly affects the optical response, and can serve as a key tuning parameter in tailoring the polaritonic patterns. By shaping α-MoO3 nanocavities with different geometries, we observe edge-oriented and steerable hyperbolic polaritons as well as forbidden zones where the polaritons detour. The lifetime and figure of merit of the hyperbolic polaritons can be regulated by the edge aspect ratio of nanocavity. The possibility to manipulate the propagation of polaritons is limited by the isotropy of 2D materials like graphene and hexagonal boron nitride. Here, the authors exploit the anisotropy of α-MoO3 and study edge tailored hyperbolic polariton manipulation in α-MoO3 nanocavities via real space nanoimaging. [ABSTRACT FROM AUTHOR]

All-dielectric nanostructures have recently opened exciting opportunities for functional nanophotonics, owing to their strong optical resonances along with low material loss in the near-infrared range. Pushing these concepts to the visible range is hindered by their larger absorption coefficient, thus encouraging the search for alternative dielectrics for nanophotonics. Here, we employ bandgap engineering to synthesize hydrogenated amorphous Si nanoparticles (a-Si:H NPs) offering ideal features for functional nanophotonics. We observe significant material loss suppression in a-Si:H NPs in the visible range caused by hydrogenation-induced bandgap renormalization, producing strong higher-order resonant modes in single NPs with Q factors up to ~100 in the visible and near-IR range. We also realize highly tunable all-dielectric meta-atoms by coupling a-Si:H NPs to photochromic spiropyran molecules. ~70% reversible all-optical tuning of light scattering at the higher-order resonant mode under a low incident light intensity is demonstrated. Our results promote the development of high-efficiency visible nanophotonic devices. Large absorption of high-index semiconductors has hindered the application of all dielectric nanostructures in the visible range. Here, the authors present bandgap-engineered hydrogenated amorphous Si nanoparticles with Q-factors up to 100 and their integration with photochromic molecules as tunable meta-atoms. [ABSTRACT FROM AUTHOR]