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Detailed modelling of masonry arch bridges and viaducts presents unique computational challenges. Not only do such structures exhibit complex nonlinear behaviour, but they are also difficult to describe within a consistent computational framework for high-fidelity simulations, due to the range of interactive components with varying geometric characteristics. This paper presents a novel parametric model design tool for the generation of detailed 3D FE meshes of realistic masonry arch bridges and viaducts. This tool has been developed according to a modular description as an add-on component within the Rhino – Grasshopper environment. It allows for modular complex bridge assemblages with independent definition of the key viaduct parts, including arch barrels, spandrel walls, piers as well as multi-layered fill. Moreover, new parts can be seamlessly introduced into the framework due to its modular nature. Notably, as all components are geometrically addressable, it is possible to further enhance the model generation tool by adding non-standard routines to create more complex geometry than that allowed by the current parametric definition. Importantly, the developed strategy enables variable fidelity model generation, where different segments of an analysed viaduct can be represented by meso‑ and/or macro-scale masonry descriptions at different levels of detail. This approach further enables the consideration of initial damage in the brick/blockwork, which is a very common feature of many existing masonry bridges and viaducts.

Robotic-assisted laparoscopic pyeloplasty (RALP) has been gaining acceptance among paediatric urologists.To compare surgical variables and clinical outcomes, including complications and success rate, with RALP using the transperitoneal (T-RALP) and retroperitoneal (R-RALP) approaches.We performed a multicentre, prospective, cohort study (NCT03274050) between November 2016 and October 2021 in three paediatric urology teaching centres (transperitoneal approach,We performed dismembered pyeloplasty using running monofilament 6-0 absorbable suture.We assessed intra- and postoperative morbidity (primary outcome) and success (secondary outcome). Data were expressed as medians and interquartile range (25th and 75th percentiles) for quantitative variables, and analysed comparatively.We operated on 106 children (T-RALP,In selected children, RALP is safe and effective using either the transperitoneal or the retroperitoneal approach, with a shorter hospital stay after R-RALP.In our multicentre, prospective study, we compared the results and complications of robotic-assisted laparoscopic pyeloplasty (RALP) using the transperitoneal and retroperitoneal approaches. We found that RALP is safe and effective using either approach, with a shorter hospital stay after R-RALP.

The paper presents a novel effective macro-modelling approach for masonry arches and bridges under cyclic loading, including dynamic actions induced by earthquakes. It utilises an anisotropic material model with embedded discontinuities to represent masonry nonlinearities. Realistic numerical simulations of masonry arch bridges under static and dynamic loading require accurate models representing the anisotropic nature of masonry and material nonlinearity due to opening and closure of tensile cracks and shear sliding along mortar joints. The proposed 3D modelling approach allows for masonry bond via simple calibration, and enables the representation of tensile cracking, crushing and shear damage in the brickwork. A two-scale representation is adopted, where 3D continuum elements at the structural scale are linked to embedded nonlinear interfaces representing the meso-structure of the material. The potential and accuracy of the proposed approach are shown in numerical examples and comparisons against physical experiments on masonry arches and bridges under cyclic static and dynamic loading.

Background Although over one hundred equations have been developed to predict the energy expenditure of individuals, none are sensitive to weight change in assessment of resting metabolic rate (RMR) before and after weight loss. Objective To formulate adjusted equations for overweight and obese individuals and to compare their accuracy with existing prediction RMR equations before and after weight loss. Subjects/materials This is historical prospective study. Participants included 39 overweight and obese men and women before and after losing 10–20% from baseline weight on a diet and physical activity regimen for at least three months. Pre and post weight loss measured RMR results were compared to estimated RMR using several existing prediction equations: Harris and Benedict, Ravussin and Bogardus, and Mifflin et al. To improve the accuracy of these prediction equations, we suggest new equations adjusted for weight loss, based on measured RMR and evaluated their accuracy. Results Pre and post weight loss data indicated: significant fat reduction in both genders; reduction in free-fat mass only in men, and a significant decrease in measured RMR only in women. Our suggested equations were the most accurate and closest to measured RMR in both genders, in comparison to the Harris and Benedict, Ravussin and Bogardus, and Mifflin et al equation results. Estimated RMR using the latter equations was significantly lower than measured RMR in both genders at pre and post weight loss (P Conclusions This study highlights the need for adjusting RMR equations before and after weight loss in overweight and obese individuals. Further research is needed to validate our suggested equations.

We consider a binary classification problem in which the class label is given in the form of a discriminant function that satisfies a monotone constraint. That is, the degree of confidence that an object belongs to a class can not decrease as one of the input features increases. This manuscript examines how such a discriminant function can be trained on the basis of a labeled data set. Two alternative quality measures are considered. One of them is the AUC, which is based on the ROC analysis. The second is encouraged by the Neyman-Pearson lemma, which aims to maximize the ratio of correctly classified to misclassified examples. We propose an approach in which feature space is partitioned into quality layers that can then effectively compute the discriminant function. We prove that the resulting discriminant function is optimal with respect to the two quality measures mentioned, which indicates, among other things, the equivalence of these two quality measures. We also show that the associated optimal partitioning of feature space is unique, and provide a polynomial training algorithm for generating this partitioning.

The economics of dividend policy has focused on the single tight narrative that dividends keep managers honest, mitigating concerns that they over-invest. This article provides a critique of that agency narrative, arguing that pressure from short-term focused investors, executives and board members pushes the firm into preemptive actions of returning too much cash via dividends. We analyze three channels of influence for investor pressure through 1) threat of takeovers, 2) shareholder value oriented corporate governance, measured by director independence and board equity incentives, and 3) trading and institutional ownership patterns. We find that firms adopt a higher dividend payout to discourage takeover bids. Also, FTSE 100 firms, that are most focused on shareholder value governance in the form of equity-based compensation and a higher share of independent directors, display a higher dividend payout. Frequency of trading and ownership by transient investors seeking current profits also predict increased dividend payout. Traditional agency theory, focused on dividends as a tool for managerial discipline, is not strongly supported by the results, which rather support a narrative of short-term investor pressure on firms irrespective of investment opportunities.

Whether synaptic transmission is excitatory or inhibitory depends, to a large extent, on whether the ion channels that open upon binding the released neurotransmitter conduct cations or anions. The mechanistic basis of the opposite charge selectivities of Cys-loop receptors has only recently begun to emerge. It is now clear that ionized side chains—whether pore-facing or buried—in the first α-helical turn of the second transmembrane segments underlie this phenomenon and that the electrostatics of backbone atoms are not critically involved. Moreover, on the basis of electrophysiological observations, it has recently been suggested that not only the sign of charged side chains but also their conformation are crucial determinants of cation-anion selectivity. To challenge these ideas with the chemical and structural rigor that electrophysiological observations naturally lack, we performed molecular dynamics, Brownian dynamics, and electrostatics calculations of ion permeation. To this end, we used structural models of the open-channel conformation of the α1 glutamate-gated Cl− channel and the α1 glycine receptor. Our results provided full support to the notion that the conformation of charged sides chains matters for charge selectivity. Indeed, whereas some rotamers of the buried arginines at position 0′ conferred high selectivity for anions, others supported the permeation of cations and anions at similar rates or even allowed the faster permeation of cations. Furthermore, we found that modeling glutamates at position −1′ of the anion-selective α1 glycine receptor open-state structure—instead of the five native alanines—switches charge selectivity also in a conformation-dependent manner, with some glutamate rotamers being much more effective at conferring selectivity for cations than others. Regarding pore size, we found that the mere expansion of the pore has only a minimal impact on cation-anion selectivity. Overall, these results bring to light the previously unappreciated impact of side-chain conformation on charge selectivity in Cys-loop receptors.

Left ventricular assist devices (LVADs) can serve as a bridge to transplant or destination therapy for patients with advanced heart failure. Implantation of LVADs is known to be associated with increases in anti-HLA antibodies, but less is known about how autoantibody levels change with the use of these devices.Autoantibody levels were quantified with the use of customized antigen microarrays in 22 patients both before and after LVAD. We observed an increase (1.5- to 2-fold) in 14 IgG autoantibodies in the serum of patients after LVAD, including autoantibodies against cardiac proteins (myosin, troponin I, tropomyosin), DNA, and structural proteins (collagen, laminin). There was also a small but significant rise in total serum IgG after LVAD. Increases in autoantibodies after LVAD were positively associated with increases in calculated panel-reactive antibody class II (P = .05) and negatively correlated with age (r = -0.45; P.05). Cytokines were evaluated to gain insights into the mechanism of antibody generation, and we observed a positive correlation between total IgG levels after LVAD and the level of monocyte chemoattractant protein 1 (r = 0.60; P.05).LVAD implantation is associated with increases in IgG autoantibodies, anti-HLA antibodies, and total IgG. Increases in IgG after LVAD implantation may relate to an inflammatory response triggered by these devices.

When public institutions do not support information disclosure and contract enforcement, controlling owners may compensate by setting up ownership networks that facilitate the exchange of resources and alignment of interests. We examine how firms’ controlling owners draw power from ownership networks to provide access to resources for or to expropriate resources from their firms. Horizontal power originates from network centrality and is associated with resource access whereas vertical power originates from principal-principal agency conflicts and is associated with exploitation of minority shareholders. We highlight the impact of horizontal and vertical power through their interaction effects with transparency and disclosure (TD) practices on fixed investments and performance in Russian firms. We find that TD and horizontal power or connectedness are substitutes, while whereas TD and vertical power are complements in their effects on fixed investment and firm performance. Without a strong commitment to TD, powerful owners may thus deprive the firm of productive investments.

Share repurchases have come under criticism as they may be used for earnings management and take capital away from productive investment. However, share repurchases can also reduce the agency costs of free cash flow and offset the dilution of current shareholders. Whether firms engage in good or manipulative share repurchases can crucially hinge on the quality of corporate governance. Using UK firm panel data, we study the effect of independent directors on repurchase policies. Our results indicate that board independence increases the propensity to engage in share repurchases. Moreover, board independence attenuates the harmful effect of manipulative share repurchases on employment growth. Our approach exploits the passage of a corporate governance reform which provided a unique opportunity to tease out the causal impact of independent directors on share repurchases. Our findings advocate in favor of more active involvement of independent directors in payout policies.

In this paper, we contribute to the literature on institutional determinants of IPO valuation. We introduce the concept of ‘legal signaling,’ which focuses on the perception of the quality of law and thus complements the existing institutional approaches to IPO valuation which consider the quality of the positive law (‘standard view’) and firm-level corporate governance practices (‘firm signaling view’). Our approach explicitly models the difference between the effect of the positive law and the effect of the perception of law on IPO value. Based on a worldwide longitudinal dataset of IPO performance across a large number of countries, we find strong support for the claim that the perception of the quality of law is more important than its actual quality to explain post-IPO firm value. This effect holds regardless of whether the law’s quality is correctly perceived or misperceived. Overall, our findings underscore the need for a more sophisticated theorization of the ways in which law affects entrepreneurial finance.

Innovative incremental bulk forming (IBF) process dedicated to form integral elements for the aerospace industry is presented in the paper. Particular attention is put on analysis of advantages and disadvantages of this process, as well as on detailed evaluation of material flow characteristics across different length scales. Thus, a multi scale numerical model of the IBF process was established based on the isotropic hardening law at the macro scale and digital material representation concept connected with the crystal plasticity theory at the micro scale. Numerical results are also supported by a series of experimental investigations realized at the prototype of the IBF press.

The COVID-19 pandemic has resulted in governments playing increasingly prominent roles as active economic agents. However, state capitalism does not necessarily serve broad developmental purposes, and rather can be directed to supporting sectional and private interests. As the literature on variegated capitalism alerts us, governments and other actors regularly devise fixes in response to a systemic crisis, but the focus, scale, and scope of the interventions vary considerably, according to the constellation of interests. Rapid progress with vaccines notwithstanding, the UK government's response to COVID-19 has been associated with much controversy, not only because of an extraordinarily high death rate, but also because of allegations of cronyism around the granting of government contracts and bailouts. We focus on the latter, investigating more closely who got bailed out. We find that badly affected sectors (e.g. hospitality, transportation) and larger employers were more likely to get bailouts. However, the latter also favored the politically influential and those who had run up debt profligately. Although, as with state capitalism, crony capitalism is most often associated with emerging markets, we conclude that the two have coalesced into a peculiarly British variety, but one that has some common features with other major liberal markets. This might suggest that the eco-systemic dominance of the latter is coming to an end, or, at the least, that this model is drifting towards one that assumes many of the features commonly associated with developing nations.

State interventions in markets assume varieties of forms in different economic systems. To capture this variety, we consider state capitalism as a multidimensional concept, first reviewing its historical evolution from both practical and scholarly vantages. We describe several dimensions of state capitalism and demonstrate how cross-national variations can be captured through positioning countries along these dimensions. We use cross-sectional data for a large sample of countries to derive factors that represent key dimensions of state capitalism. We demonstrate how cross-national and historical variation in state capitalism is captured by this Virtual Special Issue and offer suggestions for future research.

Summary Background Positive surgical margins (PSMs) at radical prostatectomy (RP) are generally recognized as a surrogate of poor or difficult dissection of the prostatic gland. In open RP cohorts, obesity seems to be associated to an increased risk of PSMs, probably due to the technical challenge that obese men pose to surgical access. Minimally invasive RP has been claimed to possibly reduce PSM rate. Aim of the study was to explore the impact of obesity and body habitus on PSM risk and their localisation during laparoscopic and robotic-assisted RP. Materials and methods We reviewed 539 prospectively enrolled patients undergoing laparoscopic and robotic-assisted RP with pT2 prostate cancer. The outcome measured was rate of PSM according to the BMI and surgical approach (laparoscopic vs robotic-assisted). Patients were categorized in BMI 2 , BMI 25-29.9 kg/m 2 and BMI >30 kg/m 2 groups respectively and compared using Kruskall-Wallis or χ 2 test, as appropriate. Uni- and multivariate logistic regression models were constructed to assess the impact of BMI and surgical technique on PSM risk. Results Overall, 127 (24%) of men had PSMs detected at final specimen evaluation. Mean PSM length was 3.9 ± 3.4 mm, and 30 (6%) men presented significant margins ≥ 4 mm. Analysing the rate of PSMs across BMI categories, no significant association between increased BMI and PSM was detected (all P > 0.48). On uni- and multivariate logistic regression BMI was not a statistically significant risk factor for PSM ( P = 0.14), nor was the minimally invasive technique (laparoscopic vs robotic-assisted) ( P = 0.54). Conclusions In this study obese men do not appear to have a significant increase in risk of PSMs at RP compared to lean and overweight men when operated by a minimally invasive approach. The magnified vision and increased access to the pelvis allowed by a laparoscopic and robotic-assisted approach may be accountable for our findings. Larger studies are needed to validate our results. Level of proof 4.