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As the global elderly population expands, the associated risks of longevity intensify, presenting significant challenges to traditional retirement security systems. We study actuarial fairness in tontines under the Volterra mortality framework, integrating long-range dependence mortality models rates with tontine structures. Initially, we establish an optimal tontine model for a homogeneous tontine under this framework. However, according only to individual actuarial fairness can neglect the collective nature of tontines. So we propose a hybrid optimization model that accounts for age and wealth discrepancies affecting payment amounts and the collective fairness. Specially, we first apply the f-value fairness measure in age-heterogeneous tontines for assessing fairness. Our results reveal that while the model ensures actuarial fairness at the group level, relative payments are lower for older age groups. By incorporating dynamic mortality modeling through the Volterra mortality framework, our work demonstrates that this comprehensive scheme significantly enhances the robustness and sustainability of retirement security systems. These findings provide valuable insights for the future integration of dynamic mortality models with innovative retirement income structures.
The lattice walks in the plane starting at the origin $\mathbf {0}$ with steps in $\{-1,0,1\}^{2}\setminus \{\mathbf {0}\}$ are called king walks. We investigate enumeration and divisibility for higher dimensional king walks confined to certain regions. Specifically, we establish an explicit formula for the number of $(r+s)$-dimensional king walks of length n ending at $(a_1,\ldots ,a_r,b_1,\ldots ,b_s)$ which never dip below $x_i=0$ for $i=1,\ldots ,r$. We also derive divisibility properties for the number of $(r+s)$-dimensional king walks of length p (an odd prime) through group actions.
The effect of Stokes number on turbulence modulation in particle-laden channel flow is investigated through four-way coupled point-particle direct numerical simulations, with the mass loading fixed at 0.6 and the friction Stokes number $St^+$ varying from 3 to 300. A full transition pathway is observed, from a drag-enhanced to a drag-reduced regime, eventually approaching the single-phase state as $St^+$ increases towards 300. A set of transport equations for the particle phase is derived analytically to characterise the interphase coupling, within the framework of the point-based statistical description of particle-laden turbulence. By virtue of this, two dominant mechanisms are identified and quantitatively characterised: a positive, particle-induced extra transport that decreases monotonically with increasing $St^+$, and a negative, particle-induced extra dissipation that varies non-monotonically with $St^+$. The coupling of these two mechanisms leads to a direct contribution of the particle phase to the shear stress balance, the turbulent kinetic energy budgets and the Reynolds stress budgets. Consequently, as $St^+$ increases, the self-sustaining cycle of near-wall turbulence transitions from being augmented to being suppressed and, eventually, returns to the single-phase state. This gives rise to an indirect effect, manifested as a non-monotonic modulation of Reynolds shear stress and turbulence production rate. Taken together, complex interplays between particle-modified turbulent transport, particle-induced extra transport and extra dissipation are analysed and summarised, providing a holistic physical picture composed of consistent interpretations of turbulence modulation induced by small heavy particles.
The present study was conducted to test the hypothesis that L2 speakers have fuzzy L2 word orthographic representations and this results in lexical confusions. A medium-term priming lexical decision task was used where orthographic neighbors (e.g., clever-clover) were presented as primes and targets. Form facilitation was predicted to be observed for orthographic neighbor, word prime-target pairs in L2 (but not in L1) because an L2 word prime and target with fuzzy orthographic representations would be processed like a repeated word leading to repetition priming. Contrary to our prediction, the present study, where native speakers of American English and proficient Korean learners of English were recruited, found form facilitation both in L1 and L2. However, the modulating role of word frequency and orthographic precision in form priming was found only in L2. This suggests that the form facilitation in L2 was qualitatively different from that in L1. We propose that the form facilitation in L1 occurred because the sublexical orthographic representations of the target and their association with corresponding phonological components were strengthened by the prime whereas form facilitation in L2 occurred due to form confusion caused by obscure boundaries of the orthographic representations of the L2 word prime and target.
Multicenter clinical trials are essential for evaluating interventions but often face significant challenges in study design, site coordination, participant recruitment, and regulatory compliance. To address these issues, the National Institutes of Health’s National Center for Advancing Translational Sciences established the Trial Innovation Network (TIN). The TIN offers a scientific consultation process, providing access to clinical trial and disease experts who provide input and recommendations throughout the trial’s duration, at no cost to investigators. This approach aims to improve trial design, accelerate implementation, foster interdisciplinary teamwork, and spur innovations that enhance multicenter trial quality and efficiency. The TIN leverages resources of the Clinical and Translational Science Awards (CTSA) program, complementing local capabilities at the investigator’s institution. The Initial Consultation process focuses on the study’s scientific premise, design, site development, recruitment and retention strategies, funding feasibility, and other support areas. As of 6/1/2024, the TIN has provided 431 Initial Consultations to increase efficiency and accelerate trial implementation by delivering customized support and tailored recommendations. Across a range of clinical trials, the TIN has developed standardized, streamlined, and adaptable processes. We describe these processes, provide operational metrics, and include a set of lessons learned for consideration by other trial support and innovation networks.
Both multifocal motor neuropathy (MMN) and chronic inflammatory demyelinating polyneuropathy (CIDP) are chronic progressive immune-mediated peripheral neuropathies without sensory loss. We aimed to explore the different features of ultrasonographic and electrophysiological changes among MMN, motor CIDP and typical CIDP patients.
Methods:
Nerve ultrasonographic studies were performed in 19 patients with MMN, 15 patients with motor CIDP and 117 patients with typical CIDP. Cross-sectional areas (CSAs) were measured on the bilateral median and ulnar nerves and brachial plexus. Nerve conduction studies (NCSs) were performed on the median and ulnar nerves.
Results:
In patients with MMN and typical CIDP, the percentage enlargement in the brachial plexus (MMN 45.7%, typical CIDP 78%) was similar to that in the arm (MMN 42.9%, typical CIDP 76.8%) and forearm (MMN 42.9%, typical CIDP 79.4%). However, in patients with motor CIDP, the percentage enlargement in the brachial plexus (74.1%) was more pronounced than in the arm (65.5%) and forearm (58.6%). The CMAPerb/CMAPaxilla in MMN was significantly higher than in motor CIDP (median nerve, 0.82 ± 0.28 for MMN and 0.60 ± 0.37 for motor CIDP, P = 0.017). The CSA decreased in the order of typical CIDP, motor predominant CIDP (MPred-CIDP), pure motor CIDP (PM-CIDP) and MMN. The motor nerve conduction velocity increased in the order of typical CIDP, MPred-CIDP, PM-CIDP and MMN. A total of 3/6 PM-CIDP and 3/3 MPred-CIDP patients responded to steroid treatment.
Conclusion:
Treatment response, nerve ultrasonography and NCS in MMN, PM-CIDP, MPred-CIDP and typical CIDP constitute a spectrum.
Studies investigating phonological processing indicate that words with high regularity/consistency in pronunciation or high frequency positively impact reading speed and accuracy. Such effects of consistency and frequency have been demonstrated in Japanese kanji words and are known as consistency and frequency effects. Using a mixed-effects model analysis, this study reexamines the two effects in Chinese–Japanese second-language (L2) learners with two different L2 proficiency levels. The two effects are robustly replicated in oral reading tasks; in particular, the performance of intermediate learners is similar to that of Japanese semantic dementia patients, whose reading accuracy is affected by sensitivity to the statistical properties of words (i.e., reading consistency and lexical frequency). These results are explained by the interaction between semantic memory and word statistical properties. Moreover, the interaction highlights the important consequences of statistical learning underlying L2 phonological processing.
With the widespread use of high-fat diets (HFD) in aquaculture, the adverse effects of HFD on farmed fish are becoming increasingly apparent. Creatine has shown potential as a green feed additive in farmed fish; however, the potential of dietary creatine to attenuate adverse effects caused by high-fat diets remains poorly understood. To address such gaps, this study was conducted to investigate the mitigating effect of dietary creatine on HFD-induced disturbance on growth performance, hepatic lipid metabolism, intestinal health and muscle quality of juvenile largemouth bass. Three diets were formulated: a control diet (10·20 % lipid), a high-fat diet (HFD, 18·31 % lipid) and HFD with 2 % creatine (HFD + creatine). Juvenile largemouth bass (3·73 (sem 0·01) g) were randomly assigned to three diets for 10 weeks. The key findings were as follows: (1) the expression of muscle growth-related genes and proteins was stimulated by dietary creatine, which contributes to ameliorate the adverse effects of HFD on growth performance; (2) dietary creatine alleviates HFD-induced adverse effects on intestinal health by improving intestinal health, which also enhances feed utilisation efficiency; (3) dietary creatine causes excessive lipid deposition, mainly via lipolysis and β-oxidation. Notably, this study also reveals a previously undisclosed effect of creatine supplementation on improving muscle quality. Together, for the first time from a comprehensive multiorgan or tissue perspective, our study provides a feasible approach for developing appropriate nutritional strategies to alleviate the adverse effects of HFD on farmed fish, based on creatine supplementation.
Seminal theories in political science argue that military service is a critical driver of minority integration. However, a major obstacle bedeviling the study of military service is self-selection: individuals who are better integrated may be more likely to join the military in the first place. We address the selection problem by examining the effects of military conscription during the Vietnam War using an instrumental variables approach. Conscription during 1970–72 was decided on the basis of national draft lotteries that assigned draft numbers based on an individual’s date of birth. Using the draft lottery instrument, we find no evidence of a causal effect of military service on a range of integration outcomes from the 2000 decennial census. At least for the Vietnam era, the link between service and long-term integration is largely driven by self-selection, which points to important scope conditions for the integrationist view.
We investigate the dynamics of close-contact melting (CCM) on ‘gas-trapped’ hydrophobic surfaces, with specific focus on the effects of geometrical confinement and the liquid–air meniscus below the liquid film. By employing dual-series and perturbation methods under the assumption of small meniscus deflections, we obtain numerical solutions for the effective slip lengths associated with velocity $\lambda$ and temperature $\lambda _t$ fields, across various values of aspect ratio $\Lambda$ (defined as the ratio of the film thickness $h$ to the structure’s periodic length $l$) and gas–liquid fraction $\phi$. Asymptotic solutions of $\lambda$ and $\lambda _t$ for $\Lambda \ll 1$ and $\Lambda \gg 1$ are derived and summarised for different surface structures, interface shapes and $\Lambda$, which reveal a different trend of $\lambda$ for $\Lambda \ll 1$ and depending on the presence of a meniscus. In the context of constant-pressure CCM, our results indicate that longitudinal grooves can enhance heat transfer under the effects of confinement and a meniscus when $\Lambda \lesssim 0.1$ and $\phi \lt 1 - 0.5^{2/3} \approx 0.37$. For gravity-driven CCM, the parameters of $l$ and $\phi$ determine whether the melting rate is enhanced, reduced or nearly unaffected. We construct a phase diagram based on the parameter matrix $(\log _{10} l, \phi )$ to delineate these three regimes. Lastly, we derive two asymptotic solutions for predicting the variation in time of the unmelted solid height.
The hydrodynamic interactions between a sedimenting microswimmer and a solid wall have ubiquitous biological and technological applications. A plethora of gravity-induced swimming dynamics near a planar no-slip wall provide a platform for designing artificial microswimmers that can generate directed propulsion through their translation–rotation coupling near a wall. In this work, we provide exact solutions for a squirmer (a model swimmer of spherical shape with a prescribed slip velocity) facing either towards or away from a planar wall perpendicular to gravity. These exact solutions are used to validate a numerical code based on the boundary integral method with an adaptive mesh for distances from the wall down to 0.1 % of the squirmer radius. This boundary integral code is then used to investigate the rich gravity-induced dynamics near a wall, mapping out the detailed bifurcation structures of the swimming dynamics in terms of orientation and distance to the wall. Simulation results show that a squirmer may traverse the wall, move to a fixed point at a given height with a fixed orientation in a monotonic way or in an oscillatory fashion, or oscillate in a limit cycle in the presence of wall repulsion.
The factsheet that follows, prepared by Nan Kim in conjunction with members of the National Campaign to End the Korean War, provides an informative overview of the dangerous military standoff that has been unfolding on the Korean Peninsula ever since South Korea conducted a 4-hour artillery exercise on November 23. The exercise was conducted on Yeonpyeong Island, populated at the time by 1,000 South Korean soldiers and 1,300 civilians, about 12 kilometers from North Korea's coastline. The North – which had demanded that the South cancel the exercise prior to its start, and then according to reports repeatedly called for a halt as the South continued its exercise – responded with direct shelling of the island. This resulted in the killing of two South Korean soldiers and two civilian contractors working on a military base. (Pyongyang later expressed regret for the civilian deaths.). See CSPAN report here.
Firms adopt different strategies to achieve sustained profitable growth. We argue that the success of sustained profitable growth relies on the alignment between a firm's prior and subsequent strategy. This study views a firm's prior strategy, i.e., growth-oriented vs profit-oriented, as a primary driver of future sustained profitable growth. We adopt the resource-based view to understand the types of resources required for these two strategies. We argue that to achieve sustained profitable growth, growth-oriented firms need to enhance their firm-specific advantages by developing valuable, rare, inimitable, and non-substitutable resources such as technology and brand. In comparison, profit-oriented firms must identify versatile resources to capture growth opportunities and manage growth by successfully replicating their profitable operations. Low turnover in senior management could help profit-oriented firms achieve this goal. We find support for the arguments in a sample of 3,802 listed firms worldwide from 1992 to 2019.
Compounds (e.g., jellybeans) and list forms (e.g., jelly, beans) can be distinguished by the presence or absence of boundaries, marked by durational and pitch cues. Studies have shown that 5-year-olds learning English have acquired both cues for distinguishing compounds and lists. However, it is not clear how and when this ability is acquired by children speaking tonal languages, such as Mandarin. This study examined whether Mandarin-speaking preschoolers can use durational and pitch cues to distinguish compounds and lists and whether their productions are adult-like. Thirty-one 4-year-olds, 34 5-year-olds, 29 6-year-olds, and 43 adults participated in an elicited production experiment. Results showed that similar to English-speaking preschoolers, Mandarin-speaking preschoolers can use durational cues to mark boundaries, triggering appropriate pitch changes for distinguishing compounds and lists, though these were not fully adult-like, even in the oldest age group.
The operating goals of family firms (FFs) typically include building both economic and socioemotional wealth. Innovation is increasingly recognized as a key source for the development and growth of family firms. From the multiple dimensions of socioemotional wealth (SEW), this research has focused on how family influences a particular type of innovation – green innovation – in family firms. Using 5,071 observations from among the listed firms in Taiwan over an eight-year period (2014–2021), we examined the relationships between FFs and green innovation. The results indicate that FFs are more likely to develop green innovation than their nonfamily counterparts. In particular, there are complicated effects within different types of FFs – control deviation family firms (CDFFs).
Objectives/Goals: Aspiration causes or aggravates lung diseases. While bedside swallow evaluations are not sensitive/specific, gold standard tests for aspiration are invasive, uncomfortable, expose patients to radiation, and are resource intensive. We propose the development and validation of an AI model that analyzes voice to noninvasively predict aspiration. Methods/Study Population: Retrospectively recorded [i] phonations from 163 unique ENT patients were analyzed for acoustic features including jitter, shimmer, harmonic to noise ratio (HNR), etc. Patients were classified into three groups: aspirators (Penetration-Aspiration Scale, PAS 6–8), probable (PAS 3–5), and non-aspirators (PAS 1–2) based on video fluoroscopic swallow (VFSS) findings. Multivariate analysis evaluated patient demographics, history of head and neck surgery, radiation, neurological illness, obstructive sleep apnea, esophageal disease, body mass index, and vocal cord dysfunction. Supervised machine learning using five folds cross-validated neural additive network modelling (NAM) was performed on the phonations of aspirator versus non-aspirators. The model was then validated using an independent, external database. Results/Anticipated Results: Aspirators were found to have quantifiably worse quality of sound with higher jitter and shimmer but lower harmonics noise ratio. NAM modeling classified aspirators and non-aspirators as distinct groups (aspirator NAM risk score 0.528+0.2478 (mean + std) vs. non-aspirator (control) risk score of 0.252+0.241 (mean + std); p Discussion/Significance of Impact: We report the use of voice as a novel, noninvasive biomarker to detect aspiration risk using machine learning techniques. This tool has the potential to be used for the safe and early detection of aspiration in a variety of clinical settings including intensive care units, wards, outpatient clinics, and remote monitoring.
Two potential obstacles stand between the observation of a statistical correlation and the design (and deployment) of an effective intervention, omitted variable bias and reverse causality. Whereas the former has received ample attention, comparably scant focus has been devoted to the latter in the methodological literature. Many existing methods for reverse causality testing commence by postulating a structural model that may suffer from widely recognized issues such as the difficulty of properly setting temporal lags, which are critical to model validity. In this article, we draw upon advances in machine learning, specifically the recently established link between causal direction and the effectiveness of semi-supervised learning algorithms, to develop a novel method for reverse causality testing that circumvents many of the assumptions required by traditional methods. Mathematical analysis and simulation studies were carried out to demonstrate the effectiveness of our method. We also performed tests over a real-world dataset to show how our method may be used to identify causal relationships in practice.
Mapping reviews (MRs) are crucial for identifying research gaps and enhancing evidence utilization. Despite their increasing use in health and social sciences, inconsistencies persist in both their conceptualization and reporting. This study aims to clarify the conceptual framework and gather reporting items from existing guidance and methodological studies. A comprehensive search was conducted across nine databases and 11 institutional websites, including documents up to January 2024. A total of 68 documents were included, addressing 24 MR terms and 55 definitions, with 39 documents discussing distinctions and overlaps among these terms. From the documents included, 28 reporting items were identified, covering all the steps of the process. Seven documents mentioned reporting on the title, four on the abstract, and 14 on the background. Ten methods-related items appeared in 56 documents, with the median number of documents supporting each item being 34 (interquartile range [IQR]: 27, 39). Four results-related items were mentioned in 18 documents (median: 14.5, IQR: 11.5, 16), and four discussion-related items appeared in 25 documents (median: 5.5, IQR: 3, 13). There was very little guidance about reporting conclusions, acknowledgments, author contributions, declarations of interest, and funding sources. This study proposes a draft 28-item reporting checklist for MRs and has identified terminologies and concepts used to describe MRs. These findings will first be used to inform a Delphi consensus process to develop reporting guidelines for MRs. Additionally, the checklist and definitions could be used to guide researchers in reporting high-quality MRs.
Expanded vowel or tone space in IDS has traditionally been interpreted as evidence of enhanced acoustic contrasts. However, emerging evidence from various languages shows that the within-category acoustic variability of vowels and tones also increases in IDS, offsetting the benefit of space expansion and leading to non-enhanced, or reduced acoustic contrasts. This study re-analysed a corpus of Mandarin IDS and ADS, showing that, relative to ADS, vowels and tones in IDS display greater variability, resulting in non-enhanced contrasts. Thus, given increased variability, expanded vowel or tonal space in IDS may not necessarily equate to enhanced acoustic contrasts.
DNA barcoding approaches have been successfully applied for estimating diet composition. However, an accurate quantification in the diets of herbivores remains to be achieved. In the current study, we present a novel methodology that reveals the relationship between the actual proportions (by mass) of each herbage species in the diets and the relative proportions of the ITS2 gene sequences obtained from faecal samples to evaluate the diet composition of sheep in a meadow steppe. Nine common and 12 rare species of plants were employed for formulating 6 diets, along with the addition of feed supplements for improving the growth performance of sheep. Faecal samples were collected for DNA analysis over the period spanning days 7–12. A significant positive correlation (Spearman’s ρ = 0.389) was obtained between the actual proportions (by mass) of the herbage in the diet provided and the relative abundance of ITS2 sequences obtained from the faecal samples. A significant regression coefficient was found between the relative abundance of all common species and their respective herbage mass proportions. The accuracy of the relation equations, evaluated by utilizing the similarity coefficient, showed 84.69% similarity between the actual diet composition and the correct percentage. Taken together, the current study has provided empirical evidence for the accuracy and applicability of ITS2 as a DNA barcode for obtaining quantitative information about the diet composition of sheep grazing in species-rich grasslands.