Asymmetric Recognition Research Articles

Learnable Anchor Embedding for Asymmetric Face Recognition

Face verification and identification traditionally follow a symmetric matching approach, where the same model (e.g., ResNet-50 vs. ResNet-50) generates embeddings for both gallery and query images, ensuring compatibility. However, real-world scenarios often demand asymmetric matching, especially when query devices have limited computational resources or employ heterogeneous models (e.g., ResNet-50 vs. SwinTransformer). This asymmetry can degrade face recognition performance due to incompatibility between embeddings from different models. To tackle this asymmetric face recognition problem, we introduce the Learnable Anchor Embedding (LAE) model, which features two key innovations: the Shared Learnable Anchor and a Light Cross-Attention Mechanism. The Shared Learnable Anchor is a dynamic attractor, aligning heterogeneous gallery and query embeddings within a unified embedding space. The Light Cross-Attention Mechanism complements this alignment process by reweighting embeddings relative to the anchor, efficiently refining their alignment within the unified space. Extensive evaluations of several facial benchmark datasets demonstrate LAE’s superior performance, particularly in asymmetric settings. Its robustness and scalability make it an effective solution for real-world applications such as edge-device authentication, cross-platform verification, and environments with resource constraints.

Regulating Catalytic Oxidation Enantiomers Behavior by Imparting Chiral Microenvironment in Zr-Based Metal-Organic Frameworks.

Chiral inversions of enantiomers have significantly different biological activities, so it is important to develop simple and effective methods to efficiently identify optically pure compounds. Inspired by enzyme catalysis, the construction of chiral microenvironments resembling enzyme pockets in the pore space structure of metal-organic frameworks (MOFs) to achieve asymmetric enantioselective recognition and catalysis has become a new research hotspot. Here, a super-stable porphyrin-containing material PCN-224 is constructed by solvothermal method and a chiral microenvironment around the existing catalytic site of the material is created by post-synthesis modifications of the histidine (His) enantiomers. Experimental and theoretical calculations results show that the modulation of chiral ligands around Zr oxide clusters produces different spatial site resistances, which can greatly affect the adsorption and catalytic level of the enantiomeric molecules of tryptophan guests, resulting in a good enantioselective property of the material. It provides new ideas and possibilities for future chiral recognition and asymmetric catalysis.

A Chiral Hexa-amino Cyclotriphosphazene for Enantioselective Recognition of Small Organic Compounds.

Chiral recognition and separation studies are of paramount importance in research in view of their applications in asymmetric catalysis and substrate recognition in biological processes. The efficiencies of these processes are governed by the subtle differences in noncovalent interactions between the host and guest molecules. Hexakis(organoamino)phosphazenes are versatile building blocks for host-guest chemistry for their ability to act as both the donor and the acceptor of H-bonds. Herein, we report an enantiomeric pair of cyclotriphosphazenes [P3N3(NHR*)6], [R* = (R)-(CH(CH3)Ph)] (1-R) and [(S)-(CH(CH3)Ph)] (1-S), with chiral α-methylbenzylamino substituents. The chiral recognition capabilities of its R-enantiomer were further probed for several chiral organic compounds containing a range of functional groups. Among these, a remarkable guest selectivity (ξ) value of 2506 was observed for binol (BOL) in favor of its R-enantiomer. DFT-optimized structures of the host-guest pairs suggest that the multiple noncovalent interactions between the molecules in the two unique types of binding sites at the phosphazenes play a crucial role in the observed high binding selectivities.

CSINet: Channel–Spatial Fusion Networks for Asymmetric Facial Expression Recognition

Occlusion or posture change of the face in natural scenes has typical asymmetry; however, an asymmetric face plays a key part in the lack of information available for facial expression recognition. To solve the problem of low accuracy of asymmetric facial expression recognition, this paper proposes a fusion of channel global features and a spatial local information expression recognition network called the “Channel–Spatial Integration Network” (CSINet). First, to extract the underlying detail information and deepen the network, the attention residual module with a redundant information filtering function is designed, and the backbone feature-extraction network is constituted by module stacking. Second, considering the loss of information in the local key area of face occlusion, the channel–spatial fusion structure is constructed, and the channel features and spatial features are combined to enhance the accuracy of occluded facial recognition. Finally, before the full connection layer, more local spatial information is embedded into the global channel information to capture the relationship between different channel–spatial targets, which improves the accuracy of feature expression. Experimental results on the natural scene facial expression data sets RAF-DB and FERPlus show that the recognition accuracies of the modeling approach proposed in this paper are 89.67% and 90.83%, which are 13.24% and 11.52% higher than that of the baseline network ResNet50, respectively. Compared with the latest facial expression recognition methods such as CVT, PACVT, etc., the method in this paper obtains better evaluation results of masked facial expression recognition, which provides certain theoretical and technical references for daily facial emotion analysis and human–computer interaction applications.

Enantioseparation of organometallic compounds by electromigration techniques.

Over time, chiral organometallic compounds have attracted great interest in several fields, with applications going across several disciplines of chemical, biological, medical, and material sciences. In the last decades, due to advancements in molecular design and computational modeling, the chemistry of chiral transition metal complexes had a remarkable flowering, with the development of new structures for applications in asymmetric synthesis, bioinorganic chemistry, and molecular recognition. In these fields, fast chiral analysis to determine the enantiomeric purity of organometallic structures prepared by asymmetric synthesis, and for high-throughput screening of analytes, catalysts, and reactions, is very important. Capillary electrophoresis and related techniques proved to be extremely versatile for chiral analysis, showing unsurpassed advantages compared to chromatography like low consumption of materials, production of limited amounts of waste, fast equilibration, and possibility to replace easily type and concentration of the chiral selector, among others. Furthermore, electromigration techniques may be useful to gain details about the stereochemistry of the enantiomers of new compounds and to study analyte-selector noncovalent interactions at molecular level. On this basis, this short review aims to provide the reader with a comprehensive view on the enantioseparation of organometallic compounds by electromigration techniques, examining the topic from the historical perspective and showing what was made in this field so far, an essential know-how for developing new and advanced applications in the next future.

CFO overconfidence and conditional accounting conservatism

This study investigates the association between Chief Financial Officers (CFOs) overconfidence and conditional accounting conservatism. Relying on upper echelons and overconfidence theories and based on a large sample of US-listed firms’ data from 1992 to 2019 (21,626 firm-year observations), we find a statistically and economically significant negative relationship between CFO overconfidence and conditional accounting conservatism, suggesting that overconfident CFOs tend to diminish conditional accounting conservatism. These findings persist in a series of robustness tests. In the mechanism analysis, we predict that overconfident CFOs aim to convey private information by reducing conditional accounting conservatism. We prove this conjecture by observing that overconfident CFOs who adopt lower levels of conditional accounting conservatism increase earnings informativeness (i.e., the amount of information about future cash flows or earnings contained in current stock returns) and reduce their precautionary incentives to save cash. We further rule out another mechanism (i.e. compensation concerns) that may motivate overconfident CFOs to reduce conditional accounting conservatism. Moreover, we show that overconfident CFOs with higher powers are more able to minimize conditional accounting conservatism. Our study highlights the significance and motivation of overconfident CFOs in determining asymmetric recognition of good and bad news.

IFRS Mandatory Adoption and Earnings Quality in an Emerging Market: The Case of Ecuador

This paper examines changes in earnings quality, including accruals, earnings smoothing, and asymmetric loss recognition schedules, following the mandatory adoption of IFRS in Ecuador. Using 5,436 year-firm observations, we employ a differences-in-differences approach, comparing the effect of IFRS on an initial group of adopters (publicly traded companies) with non-adopters (small and medium-sized enterprises) with essentially the same financial reporting requirements. Our findings indicate a decrease in accrual levels and more timely recognition of losses, with no evidence of changes in earnings smoothing. These results suggest that companies use the increased flexibility of IFRS to meet debt holders' demand for timely loss recognition. The decrease in accruals suggests earnings management for tax purposes. This study contributes to the literature on IFRS and earnings quality by using a more robust research design and providing evidence on the consequences of IFRS adoption in an emerging market dominated by debt capital and family-owned firms.

Racial Profiling on the U-Bahn: Policing the Berlin Gap in the Schönefeld Airport Refugee Crisis

AbstractThe German Democratic Republic (GDR) treated the Berlin Wall as an official state border, but the Federal Republic of Germany (FRG) did not recognize it as an official state border and thus did not impose entry controls. This asymmetric recognition opened up a gap in the regime of border policing and turned divided Berlin into one of the most significant sources of unauthorized migration into the FRG, creating tensions in Berlin, West Germany, and western Europe more broadly. Countries including France, Denmark, and the Netherlands all pressured the FRG to shut the open border in Berlin. This article examines how West German authorities sought to respond to their demands without recognizing the Berlin Wall as a state border. West German authorities pursued two broad strategies. The first involved internalizing the border through institutionalized racial profiling in West Berlin. The second entailed externalizing the border by asking the GDR to enforce FRG visa and passport requirements. Although both forms of border policing have often been associated with the end of the Cold War, this article shows that they were adopted earlier, and in response to Cold War imperatives.

Monitoring Protein Complexation with Polyphosphazene Polyelectrolyte Using Automated Dynamic Light Scattering Titration and Asymmetric Flow Field Flow Fractionation and Protein Recognition Immunoassay.

Polyphosphazenes represent a class of intrinsically flexible polyelectrolytes with potent immunoadjuvant activity, which is enabled through non-covalent self-assembly with antigenic proteins by charge complexation. The formation of supramolecular complexes between polyphosphazene adjuvant, poly[di(carboxylatophenoxy)phosphazene] (PCPP), and a model vaccine antigen, hen egg lysozyme, was studied under physiological conditions using automated dynamic light scattering titration, asymmetric flow field flow fractionation (AF4), enzyme-linked immunosorbent assay (ELISA), and fluorescent quenching methods. Three regimes of self-assembly were observed covering complexation of PCPP with lysozyme in the nano-scale range, multi-chain complexes, and larger aggregates with complexes characterized by a maximum loading of over six hundred protein molecules per PCPP chain and dissociation constant in the micromolar range (Kd = 7 × 10-6 mol/L). The antigenicity of PCPP bound lysozyme, when compared to equivalent lysozyme solutions, was largely retained for all complexes, but observed a dramatic reduction for heavily aggregated systems. Routes to control the complexation regimes with elevated NaCl or KCl salt concentrations indicate ion-specific effects, such that more smaller-size complexes are present at higher NaCl, counterintuitive with respect to PCPP solubility arguments. While the order of mixing shows a prominent effect at lower stoichiometries of mixing, higher NaCl salt reduces the effect all together.

A protein enzyme-free strategy for fluorescence detection of single nucleotide polymorphisms using asymmetric MNAzymes

To establish protein enzyme-free and simple approach for sensitive detection of single nucleotide polymorphisms (SNPs), the nucleic acid amplification reactions were developed to reduce the dependence on protein enzymes (polymerase, endonuclease, ligase). These methods, while enabling highly amplified analysis for the short sequences, cannot be generalized to long genomic sequences. Herein, we develop a protein enzyme-free and general SNPs assay based on asymmetric MNAzyme probes. The multi-arm probe (MNAzyme-9M-13) with two asymmetric recognition arms, containing a short (9 nt) and a long (13 nt) arm, is designed to detect EGFR T790 M mutation (MT). Owing to the excellent selectivity of short recognition arm, MNAzyme-9M-13 probe can efficiently avoid interferences from wild-type target (WT) and various single-base mutations. Through a one-pot mixing, MNAzyme-9M-13 probe enables the sensitive detection of MT, without protein enzyme or multi-step operation. The calculated detection limit for MT is 0.59 nM and 0.83%. Moreover, this asymmetric MNAzyme strategy can be applied for SNPs detection in long genomic sequences as well as short microRNAs (miRNAs) only by changing the low-cost unlabeled recognition arms. Therefore, along with simple operation, low-cost, protein enzyme-free and strong versatility, our asymmetric MNAzyme strategy provides a novel solution for SNPs detection and genes analysis.

Asymmetric song recognition does not influence gene flow in an emergent songbird hybrid zone

Abstract Hybrid zones can be used to examine the mechanisms, like song recognition, that affect reproductive isolation and speciation. Song has mixed support as a driver of speciation; we did not find song to be associated with reproductive isolation in White-crowned Sparrow subspecies (Zonotrichia leucophrys pugetensis and Z. l. gambelii). We examined an emerging secondary contact zone in these subspecies by measuring song variation, song recognition, plumage, morphology, and mitochondrial DNA (mtDNA). Plumage and morphological characters provided evidence of hybridization in the contact zone, with some birds possessing intermediate phenotype and song characteristics, and some possessing discordant phenotype and mitochondrial haplotype. Playback experiments revealed asymmetric song recognition: male pugetensis displayed greater response to their own song than gambelii song, whereas gambelii did not discriminate significantly. If female choice operates similarly to male song discrimination, we predicted asymmetric gene flow, resulting in a greater number of hybrids with gambelii mtDNA. Contrary to our prediction, more gambelii and putative hybrids in the contact zone possessed pugetensis mtDNA haplotypes, possibly due to greater pugetensis abundance and female-biased dispersal.

Catalytic Enantioselective Synthesis of Helicenes.

Helicenes and helicene-like molecules, usually containing multiple ortho-fused aromatic rings, possess unique helical chirality. These compounds have found a wide range of important applications in many research fields, such as asymmetric catalysis, molecular recognition, sensors and responsive switches, circularly polarized luminescence materials and others. However, the catalytic enantioselective synthesis of helicenes was largely underexplored, when compared with the enantioselective synthesis of molecules bearing other stereogenic elements (e.g. central chirality and axial chirality). Since the pioneer work of asymmetric synthesis of helicenes via enantioselective [2+2+2] cycloaddition of triynes by Stará and Starý, last two decades have witnessed the tremendous development in the catalytic enantioselective synthesis of helicenes. In this review, we comprehensively summarized the advances in this field, which include methods enabled by both transition metal catalysis and organocatalysis, and provide our perspective on its future development.

Asymmetric and non-stoichiometric glycoprotein recognition by two distinct antibodies results in broad protection against ebolaviruses

Several ebolaviruses cause outbreaks of severe disease. Vaccines and monoclonal antibody cocktails are available to treat Ebola virus (EBOV) infections, but not Sudan virus (SUDV) or other ebolaviruses. Current cocktails contain antibodies that cross-react with the secreted soluble glycoprotein (sGP) that absorbs virus-neutralizing antibodies. By sorting memory B cells from EBOV infection survivors, we isolated two broadly reactive anti-GP monoclonal antibodies, 1C3 and 1C11, that potently neutralize, protect rodents from disease, and lack sGP cross-reactivity. Both antibodies recognize quaternary epitopes in trimeric ebolavirus GP. 1C11 bridges adjacent protomers via the fusion loop. 1C3 has a tripartite epitope in the center of the trimer apex. One 1C3 antigen-binding fragment anchors simultaneously to the three receptor-binding sites in the GP trimer, and separate 1C3 paratope regions interact differently with identical residues on the three protomers. A cocktail of both antibodies completely protected nonhuman primates from EBOV and SUDV infections, indicating their potential clinical value.

Epistemic Signaling Games for Cyber Deception With Asymmetric Recognition

This study provides a model of cyber deception with asymmetric recognition represented by private beliefs. Signaling games, which are often used in existing works, are built on the implicit premise that the receiver's belief is public information. However, this assumption, which leads to symmetric recognition, is unrealistic in adversarial decision making. For a precise evaluation of risks arising from cognitive gaps, this paper proposes epistemic signaling games based on the Mertens-Zamir model, which explicitly quantifies players' asymmetric recognition. Equilibria of the games are analytically characterized with an interpretation.

Structural basis for recognition of the Hsp90 closed, ATP state by the TPR‐containing co‐chaperone FKBP51

The Hsp90 molecular chaperone drives activation of hundreds of client proteins in the cell through an ATP-dependent conformational cycle guided by distinct co-chaperone regulators. The FKBP51 immunophilin co-chaperone binds Hsp90 through its tetratricopeptide repeat (TPR) domain and catalyzes peptidyl-prolyl isomerase (PPIase) activity during the folding of kinases, nuclear receptors and tau. However, for many TPR cochaperones, the protein:protein interactions and mechanisms which enable Hsp90 specificity and regulation in the folding pathway remain unclear. High resolution structure of the Hsp90:FKBP51:p23 complex was determined using cryo-electron microscopy (EM). Native gel electrophoresis, gel filtration chromatography coupled with multiangle light scattering, and negative stain-EM were used to test interaction of FKBP51/p23 with Hsp90 in different nucleotide binding states. The structure of the Hsp90:FKBP51:p23 complex was verified with mutational analysis and site-specific photocrosslinking experiments. We developed in vitro conditions that promote and stabilize the closed, ATP conformation of Hsp90, enabling characterization of binding interactions between defined open (apo) and closed (ATP) states. We find that FKBP51 preferentially binds the closed, ATP state, forming a complex with a 2:1 stoichiometry that is further stabilized by p23 binding. Using cryo-EM we determined a 3.3 Å structure the Hsp90:FKBP51:p23 complex that reveals distinct contacts by the TPR domain of FKBP51 that define its asymmetric interaction and recognition of C-terminal Hsp90 dimer. We propose a model in which helix 7 of the TPR domain of FKBP51 functions as a critical specificity element for engaging Hsp90 in the p23-stabilized, ATP state to promote client maturation. This arrangement flexibly positions the FK1 domain of FKBP51 adjacent Hsp90 client binding sites in a manner we predict facilitates site-specific PPIase activity towards clients in coordination with the Hsp90 chaperone cycle.

Dual-polarized bidirectional three-dimensional metamaterial absorber with transmission windows

In this paper, we proposed a dual-polarized bidirectional three-dimensional metamaterial absorber (3D-MA) with transmission windows. This 3D-MA can achieve a broadband absorption in the range of 3.45-4.82 GHz for the forward incident wave. Meanwhile, it possesses another absorption band in the range of 1.89-3.84 GHz for backward incident waves. Due to its hollow 3D lattice structure, it also has two additional transmission windows at low frequency and high frequency bands. The design is insensitive to polarization and maintains good angular stability for oblique incidence up to 40°. In order to verify the performance of the design, a prototype was manufactured and measured. The measurement results agree well with the simulation. By studying normalized equivalent impedance and surface current distribution of the 3D-MA, the physical mechanism of the MA is clarified. The MA breaks the symmetrical transmission through the delicate designed 3D unit cell. The asymmetric absorption feature greatly expands the function of MA by providing an additional absorption band for backward incident waves. It also provides a new degree of freedom for the design of electromagnetic metamaterials. The proposed design has important application prospects in the field of radar asymmetric recognition, detection, and stealth.

Asymmetric and Non-Stoichiometric Recognition Results in Broad Protection Against Ebolaviruses by a Two-Antibody Cocktail

There are multiple known ebolaviruses that each cause outbreaks of severe disease. Medical countermeasure development has thus far focused on just one, Ebola virus, resulting in two vaccines and several monoclonal antibodies that provide clinical benefit. However, none of these countermeasures can be used to prevent disease or treat patients infected with other ebolaviruses such as Sudan virus. Further, all treatments evaluated clinically thus far contain antibodies that cross-react to sGP, the abundantly shed version of the glycoprotein, which threatens to absorb otherwise neutralizing antibody responses. Using sera from survivors of Ebola virus infection, we performed targeted sorting of memory B cells that recognize multiple ebolaviruses. We isolated two mAbs, 1C3 and 1C11, that do not cross-react to sGP, potently neutralize and protect rodents from disease. The broad reactivity of both antibodies is based on their recognition of quaternary epitopes of the ebolavirus glycoprotein complex: 1C11 bridges the fusion loop of one monomer to the adjacent monomer in the glycoprotein trimer, whereas 1C3 binds to the center apex of the trimer, in a position that enables a single antigen-binding fragment to anchor simultaneously to the three ebolavirus receptor-binding sites on the timers. In this unique tripartite epitope, identical residues on the three GP monomers each form different interactions with a separate portion of the antibody paratope. The combination of both antibodies completely protected non-human primates from Ebola and Sudan virus infection, indicating their potential future use in the clinic.

Asymmetric acoustic signal recognition led to asymmetric gene flow between two parapatric frogs

AbstractCorrect discrimination between courtship signals could help to maintain genetic integrity between closely related species. However, asymmetric usage of signals might cause asymmetric gene flow across the contact zone. Buergeria choui and B. otai are sibling-species with a parapatric distribution pattern in Taiwan, having two narrow contact zones on the east and west sides of the island. Combining behavioural experiments with genome-wide RAD-seq analyses, we test whether the ability of signal recognition influences genetic introgression across their species boundary. The playback experiments show that all B. choui populations respond strongest to their own ‘cricket’ trills, while the western population of B. otai have evolved a strong level of reproductive character displacement by showing the inclusive usage of the unique ‘chicken’ signals. In contrast, the eastern B. otai population uses both ‘chicken’ and ‘cricket’ trills, and has a stronger preference for the latter. The weak reproductive character displacement in the eastern population has led to asymmetry genetic introgression from B. choui toward B. otai. Our results support the prediction that a more specialized signal-user, compared to its sibling, generalized signal-user, might have a higher probability of maintaining their genetic integrity in the secondary contact region.

Asymmetrically Timely Loss Recognition and the Accrual Anomaly: Evidence From Pakistan’s Non-financial Sectors

An important role of Conditional conservatism is to align the timely expense recognition of revenue generated in terms of losses compared to the profit over negative components of accruals. Accrual anomaly shows asymmetric differential persistence for accruals and cash flows in years of economic gains rather than losses. The aim of this study to determine the asymmetric timely loss recognition and accrual anomaly of the non-financial firms listed at Pakistan Stock exchange (PSX). Top volume non-financial firms listed at PSX were taken for this study over a period of 2011 to 2018. The direct implication of this research on the pattern of pricing of accrual component of earning exhibits positive relationship of excess returns with accruals and stock returns; whereas negative relationship with earnings, market capitalization and indicator variable of profit firms. Overall, research result is consistent with Konstantinidi et al. (2015), the accrual effect on stock return is existent for earnings generated firms, while not apparent for loss firms. This evidence provides relevant information on the aspects of accrual anomaly and its association with the variables of conditional conservatism on the pricing of accrual during the profit years.

Asymmetric Timeliness of Earnings Recognition and Overestimation of Accruals Quality

This study examines the relationship between the asymmetric timeliness of earnings recognition and accruals quality. Ball and Shivakumar (2006) provide evidence that the relationship between accruals and cash flows is distorted under the linear assumption. This study estimates new measures of accruals quality after including the asymmetric timeliness of earnings recognition in Dechow and Dichev’s (2002) model and compares these with Dechow and Dichev’s accruals quality. I decompose Dechow and Dichev’s accruals quality into (1) one component after controlling for asymmetric earnings timeliness, which is unexplained by asymmetric timeliness recognition, and (2) another component that is explained incrementally by asymmetric timeliness recognition beyond three consecutive-period operating cash flows. I examine the relationship between decomposed accruals quality and earnings forecast accuracy, cost of debts, and cost of equity. Empirical findings show accruals quality significantly improves after incorporating asymmetric timeliness of earnings recognition. The accruals quality component after incorporating asymmetric timeliness shows significant relationships with earnings forecast accuracy and cost of equity, while the other component does not. This study shows that accruals quality improves when estimated by allowing a non-linear relationship with asymmetric timeliness. This measure enables users to make better decisions when evaluating firms’ operating or financing activities. Key words: Accruals Quality; Asymmetric Timeliness of Earnings Recognition; Cost of Debts; Cost of Equity; Earnings Forecast Accuracy JEL Classification: G10, M40