In the behavioral theory of the firm, decision-makers' interpretation of performance feedback information is the fundamental intermediate step between the evaluation of performance and the consequent strategic decision-making. However, such interpretations can be shaped or even distorted by the cognitive lens taken by decision-makers, such as their time concept in terms of biased cognitions of the importance and imminence of the future over the present. This study focuses on the role of a specific temporal bias (the time concept expressed in languages) in shaping the response to performance feedback. On the basis of the baseline proposition of a positive relationship between the underperformance duration (a temporal dimension of performance feedback) and acquisition behavior, we theorize and empirically examine how the future-time reference (FTR) of languages under different conditions shapes the way firms respond to repeated performance shortfalls. Using a sample of 12,309 firms from 12 countries between 2007 and 2019, we find that the FTR weakens the connection between the underperformance duration and subsequent acquisitions. Moreover, slack resources strengthen, whereas political stability weakens, this moderating effect of FTR on the underperformance duration–firm acquisition relationship.

How does family diversity affect the choice of hybrid entrepreneurship? The effect of family dynamics has received little attention in research on the mode of entry into entrepreneurship. Building on the family embeddedness perspective, we hypothesize that the diversity of family households at surface (i.e., age and gender) and deep (i.e., work experience and education background) levels impacts the entrepreneur's adoption of a full-time or hybrid mode to start a new business. We further theorize that the effects of family diversity on entrepreneurial entry decisions are moderated by income stratification, which largely determines the ways entrepreneurs deal with family diversity. Using a sample of 1,320 individual-wave observations from the China Health and Nutrition Survey (CHNS), our findings demonstrate that the choice of hybrid entrepreneurship is affected more by deep-level diversity than surface-level diversity among family households. Moreover, being from a high-strata family strengthens the relationship between surface-level diversity and the choice of hybrid entry, while weakening the effects of deep-level diversity. This study contributes to the ongoing discussion about family dynamics and entrepreneurship variations and provides important theoretical and practical implications.

In this paper, a novel special structure derived from the double-slider mechanism is presented and apply it to the design of a parallel mechanism, endowing the designed parallel mechanism with reconfigurable characteristics. First, a comprehensive analysis of the motion modes of the double-slider mechanism is carried out. By ingeniously varying the slider structure of the double-slider mechanism, a special structure capable of three distinct motion modes is obtained. This special structure is then integrated into the 3UPU parallel mechanism. As a result, the redesigned 3UPU parallel mechanism exhibits reconfigurability and can seamlessly switch among the three motion modes. Subsequently, the inverse kinematics, workspace, and singular pose of the parallel mechanism in these three modes are meticulously analyzed. Moreover, the Jacobian matrix is utilized to evaluate its flexibility and load-bearing performance. The analysis reveals that in different motion modes, all performance indicators of the mechanism are remarkable, indicating a promising application prospect. Finally, a prototype is fabricated using 3D printing technology to further validate the effectiveness of the proposed special structure. Additionally, its versatility is further explored and analyzed in-depth.

Compliant and safe human–robot interaction is an important requirement in lower limb exoskeleton design. Motivated by this need, this paper presents the design of a compatible lower limb exoskeleton with variable stiffness actuation and anthropomorphic joint mechanisms, for walking assistance and gait rehabilitation. A novel variable stiffness actuator (VSA) based on a guide-bar mechanism was designed, to provide force and impedance controllability. By changing the crank length of the mechanism, the stiffness of the actuator is adjusted in a wide range (from 0 to 1301 Nm/rad), at fast speed (about 2582 Nm/rad/s), and with low-energy cost. These features make it possible for online stiffness adjustment during one gait cycle, to change the human–robot coupling behavior and improve the performance of the exoskeleton. An anthropomorphic hip joint mechanism was designed based on a parallelogram linkage and a passive joint compensation approach, which absorbs misalignment and improves kinematic compatibility between the human and the exoskeleton joint. Furthermore, a torque control-based multimode control strategy, which consists of passive mode, active mode, and hybrid mode, was developed for different disease stages. Finally, the torque control performance of the actuator was verified by benchtop test, and experimental validations of the exoskeleton with a human subject were carried out, which demonstrate that compliant human–robot interaction was achieved, and stiffness variation benefits for control performance improvement when the control mode changes.

Research on the association between the Chinese visceral adiposity index (CVAI) and hyperuricemia (HUA) is scarce, and whether the association differs by sex is unclear. This research aimed to explore sex-specific associations between CVAI and HUA and to compare CVAI’s predictive performance with other adiposity indices using data from 22,171 adults (30–79 years) in the China Multi-Ethnic Cohort (CMEC) study (Chongqing region). The prevalence of HUA was 20.9% in men and 9.7% in women. Multivariable logistic regression analyses were utilized to assess the adjusted odds ratios (ORs) and 95% confidence intervals (CIs). After multivariable adjustment, CVAI was associated with HUA in men (OR Q4 vs. Q1 = 3.31, 95% CI 2.73, 4.03) and women (OR Q4 vs. Q1 = 7.20, 95% CI 5.12, 10.12). Moreover, Significant interactions were observed between BMI and CVAI on HUA in both sexes (all Pinteraction <0.001), with the strongest associations in those with BMI <24.0 kg/m2. The ORs (95% CI) across different BMI groups (<24.0, 24.0–27.9, ≥28.0 kg/m²) were 1.87 (1.63, 2.13), 1.65 (1.48, 1.85), and 1.30 (1.14, 1.49) for men, and 2.76 (2.18, 3.51), 2.46 (1.98, 3.07), and 1.87 (1.47, 2.39) for women, respectively. Additionally, CVAI showed satisfactory predictive performance for HUA in women, with the largest area under the receiver operating characteristic curve (AUROC) of 0.735, but not in men (0.660). These findings suggest a close association between CVAI and HUA, particularly pronounced in those with BMI <24.0 kg/m², and a stronger association in women than in men.

The setting is a tutorial on program verification in Agda. Please consult the programme for further details. [See also Appendix A.]

Deep neural networks and other modern machine learning models are often susceptible to adversarial attacks. Indeed, an adversary may often be able to change a model’s prediction through a small, directed perturbation of the model’s input – an issue in safety-critical applications. Adversarially robust machine learning is usually based on a minmax optimisation problem that minimises the machine learning loss under maximisation-based adversarial attacks. In this work, we study adversaries that determine their attack using a Bayesian statistical approach rather than maximisation. The resulting Bayesian adversarial robustness problem is a relaxation of the usual minmax problem. To solve this problem, we propose Abram – a continuous-time particle system that shall approximate the gradient flow corresponding to the underlying learning problem. We show that Abram approximates a McKean–Vlasov process and justify the use of Abram by giving assumptions under which the McKean–Vlasov process finds the minimiser of the Bayesian adversarial robustness problem. We discuss two ways to discretise Abram and show its suitability in benchmark adversarial deep learning experiments.

This work reports high-fidelity shock-tube experiments on the convergent Richtmyer–Meshkov (RM) instability at a heavy gas layer. The convergent shock tube is designed based on shock dynamics theory, significantly mitigating interface deceleration and reflected shock. As a result, long-term observation of instability growth up to nonlinear stage, free of interface deceleration and reshock, is achieved. Various types of SF$_6$ layers surrounded by air with controllable thicknesses and shapes, created using a soap film technique, are examined. For thick layers, the evolutions of the outer and inner interfaces are nearly decoupled regardless of the layer shape. The weakly nonlinear model of Wang (Phys. Plasmas,vol. 22, 2015, p. 082702), designed for cylindrical RM instability at a single interface, provides a reasonable prediction of perturbation growth at the inner interface, while slightly underestimating instability growth at the outer interface, as it neglects the effects of rarefaction wave. For thin layers, perturbation growth is fastest at either interface when both interfaces initially possess in-phase perturbations, moderate when only one interface is initially perturbed and slowest when the two interfaces have anti-phase perturbations. This variation in growth rates is due to the fact that the evolution of a thin layer is influenced by both reverberating waves and interface coupling, with each factor being highly sensitive to the layer shape. The original vortex method is extended to address the convergent RM instability by incorporating the influences of unsteady background flow, interface coupling and reverberating waves into the transport of a vortex sheet. This extended vortex method enables accurate prediction of convergent RM instability at a gas layer, covering the full range from early linear to late nonlinear stages.

Bombyx mori Tryptophanyl-tRNA synthetase (BmWARS) belongs to the family of Ic-like aminoacyl-tRNA synthetases (aaRSs), whose specific recognition of the substrate Trp, tRNA, maintains the fidelity of protein synthesis. In this study, BmWARS was cloned and characterized from the midgut of the silkworm, Bombyx mori, resulting in an open reading frame (ORF) with a full length of 1,149 bp, which can encode 382 Aa. BmWARS is localized in the cytoplasm, and is expressed in all tissues of the silkworm, with higher expression in the testis, ovary, silk gland and malpighian tubule. The expression of BmWARS was significantly up-regulated in the midgut and silk gland after infection with Bombyx mori nuclear polyhedrosis virus (BmNPV). In addition, overexpression of BmWARS inhibited BmNPV infection and replication extremely significantly, while interference with BmWARS expression promoted BmNPV infection and replication. Analysis of the immune pathways in which BmWARS may be involved revealed that the expression of the key genes of the PI3K-Akt pathway, BmPI3K, BmAkt, BmPDK1, BmeIF4E, BmS6, and p-Akt protein was significantly reduced, whereas the expression of BmPTEN, BmFoxO, and BmCaspase9 was significantly increased in the cells that overexpressed BmWARS and were infected with BmNPV. Meanwhile, the results of the study interfering with the expression of BmWARS were completely opposite to those of the study overexpressing BmWARS. This is the first report that BmWARS has antiviral effects in Bombyx mori. Moreover, BmWARS inhibits BmNPV infection and replication in Bombyx mori cells by promoting apoptosis and inhibiting cell proliferation.

The demand for separating and analysing rare target cells is increasing dramatically for vital applications such as cancer treatment and cell-based therapies. However, there remains a grand challenge for high-throughput and label-free segregation of lesion cells with similar sizes. Cancer cells with different invasiveness usually manifest distinct deformability. In this work, we employ a hydrogel microparticle system with similar sizes but varied stiffness to mimic cancer cells and examine in situ their deformation and focusing under microfluidic flow. We first demonstrate the similar focusing behaviour of hydrogel microparticles and cancer cells in confined flow that is dominated by deformability-induced lateral migration. The deformation, orientation and focusing position of hydrogel microparticles in microfluidic flow under different Reynolds numbers are then systematically observed and measured using a high-speed camera. Linear correlations of the Taylor deformation and tilt angle of hydrogel microparticles with the capillary number are revealed, consistent with theoretical predictions. Detailed analysis of the dependence of particle focusing on the flow rate and particle stiffness enables us to identify a linear scaling between the equilibrium focusing position and the major axis of the deformed microparticles, which is uniquely determined by the capillary number. Our findings provide insights into the focusing and dynamics of soft beads, such as cells and hydrogel microparticles, under confined flow, and pave the way for applications including the separation and identification of circulating tumour cells, drug delivery and controlled drug release.

Contemporary business and management research in China has advanced rapidly, making significant strides in the introduction of theoretical frameworks, research methodologies, local theory development, and practical applications. Much of this research continues to draw on Western theories, and since the reform and opening up, Chinese management research has evolved through distinct stages of globalization and localization. Today, it faces new challenges amid anti-globalization trends. At this critical juncture, the key question is whether China should continue integrating Western theories or capitalize on the opportunity to develop indigenous management theories. This paper explores the differences in scientific development concepts and focuses between China and the West, the historical trajectory of Chinese management research, and the challenges and opportunities that lie ahead. To enhance China's contribution to global management research, we propose that it is essential to sustain international collaboration, deepen understanding of frontline enterprise practices, promote micro-level research and interpretation with Chinese characteristics, and cultivate an open academic community, while optimizing the research evaluation system.

We investigate the natural oscillations of sessile drops with a central trapped bubble on a plane using linear potential flow theory, considering both free and pinned contact lines. The system is governed by the contact angle $\alpha$ and the ratio $\tau$ of inner to outer contact line radii. For bubble-containing (BC) hemispherical drops with free contact lines (referred to as free BC semi-drops), the modes mirror half of those in concentric spherical BC drops due to plane symmetry. These modes are labelled ‘plus’ (with greater inner surface deformation) and ‘minus’ (with greater outer surface deformation). As $\tau \to 0$, minus modes converge to those of bubble-free drops. Results show that varying $\alpha$ from $90^\circ$ or pinning the contact line in free BC semi-drops alters the topology of spectral lines, turning original crossings of spectral lines between minus and plus modes into avoided crossings. This shift causes minus and plus modes to form spectral trends with avoided crossings, maintaining their original spectral shapes. In an avoided crossing, two coupled modes cannot be classified as plus or minus due to their comparable inner and outer surface deformations, resulting in mode beating when both are excited, as confirmed by our direct numerical simulations. This study on the impact of inner bubbles on the spectrum may help in predicting bubble size in opaque sessile drops.

We report the first measurement of turbulent mixing developing from the convergent Richtmyer–Meshkov (RM) instability using time-resolved planar laser-induced fluorescence in a semi-annular convergent shock tube. A membraneless yet sharp interface with random short-wavelength perturbations, but controllable long-wavelength perturbations, is created by an automatically retractable plate, enhancing the reproducibility and reliability of RM turbulence experiments. The cylindrical air/SF$_6$ interface formed is first subjected to a convergent shock, then to its reflected shock and subsequently transits to turbulent mixing. It is found that the mixing width after reshock has a linear growth rate more than twice the rate in planar geometry. Also, the mixing width does not present power-law growth at late stages as in a planar geometry. However, the scalar spectrum and transition criterion obtained are similar to their planar counterparts. These findings indicate that the geometric constraint greatly affects the large scales of the flow, while having a weaker effect on the small scales. It is also found that the reflected shock significantly increases both scale separation and Reynolds number, explaining the rapid transition to turbulence following reshock.

This study aimed to assess the concordance between different anthropometric indexes in the Global Leaders Initiated Malnutrition Standards (GLIM) and the Geriatric Risk Index (GNRI) for evaluating muscle mass, while also exploring performance-based criteria for GLIM muscle content suitable for elderly patients with intermediate and advanced tumors. A total of 312 patients admitted to Shanghai Tenth People’s Hospital between September 2022 and June 2023 were retrospectively included. Nutritional assessments were conducted using the GLIM framework, employing grip strength, upper arm circumference, and calf circumference as criteria for muscle content evaluation. The diagnostic value of these tools was compared against the GNRI as a reference standard. Among the participants, 127 (40.71%) were diagnosed as malnourished by GNRI, while the GLIM assessments yielded 138 (44.23%), 128 (41.03%), and 162 (51.92%) malnutrition diagnoses based on grip strength, calf circumference, and upper arm circumference, respectively. Both GNRI and GLIM-grip strength were significantly associated with complications and length of hospital stays. Notably, using GNRI as a reference, GLIM-grip strength demonstrated good consistency in diagnosing malnutrition (K value = 0.692, P < 0.001), with calf circumference having the highest diagnostic value. In conclusion, grip strength is a practical and effective performance-based criterion within the GLIM standards and has the potential to enhance malnutrition diagnosis in elderly patients with advanced malignancies, highlighting its relevance in nutritional science.

This study investigates the stability and instability of the language control network in bilinguals using longitudinal resting-state functional magnetic resonance imaging (rs-fMRI) data. We compared the language control network of Chinese university students majoring in English with those not, using three other functional networks as controls. Results indicate that the English major group exhibits reduced stability and increased instability in the language control network compared with the non-English major group. This suggests that second language (L2) learning experience may induce adaptive neural changes. Moreover, the coexistence of stability and instability in the language control network appears less modular in the English major group, implying a more integrated response to language experience. Notably, these results were not observed in the control networks. Overall, these findings enhance the understanding of bilingual language control and the impact of L2 learning on neural plasticity.

Determining the insdel distance of linear codes is a very challenging problem. Recently, Ji et al. [‘Strict half-Singleton bound, strict direct upper bound for linear insertion-deletion codes and optimal codes’, IEEE Trans. Inform. Theory 69(5) (2023), 2900–2910] proposed their strict half-Singleton bound for linear codes that do not include the all-one vector. A natural question asks for linear codes with both large Hamming distance and insdel distance. Almost maximum distance separable (MDS) codes are a special kind of linear code with good Hamming error-correcting capability. We present a sufficient condition for the insdel distance of almost MDS codes to be bounded by the strict half-Singleton bound. In addition, we construct a class of two-dimensional near MDS codes that achieve the strict half-Singleton bound using twisted Reed–Solomon codes. Finally, we present a construction of optimal almost MDS insdel codes from Reed–Solomon codes for large dimensions.

In the contemporary maritime industry, characterised by intense competition, reduced visibility due to heavy fog is a primary cause of accidents, significantly impairing maritime operational efficiency. Consequently, investigating foggy weather navigation safety holds crucial practical significance. This paper, through an analysis and synthesis of various aspects of foggy navigation technology, including foggy navigation regulations at different ports, fog warnings, foggy vessel environmental perception and foggy auxiliary navigation systems, explores the key issues concerning vessel navigation during foggy conditions from a scientific perspective. This discussion encompasses the aspects of regulatory frameworks, standardisation, and the development of intelligent and responsive onboard equipment. Finally, the paper offers a glimpse into potential strategies for fog navigation.