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Purpose: Low-density lipoprotein cholesterol (LDL-C) recommendations differ between the 2018 American College of Cardiology/American Heart Association (ACC/AHA) and 2019 European Society of Cardiology/European Atherosclerosis Society (ESC/EAS) guidelines for patients with atherosclerotic cardiovascular disease (ASCVD) (< 70 vs. < 55 mg/dl, respectively). In the DA VINCI study, residual cardiovascular risk was predicted in ASCVD patients. The extent to which relative and absolute risk might be lowered by achieving ACC/AHA versus ESC/EAS LDL-C recommended approaches was simulated. Methods: DA VINCI was a cross-sectional observational study of patients prescribed lipid-lowering therapy (LLT) across 18 European countries. Ten-year cardiovascular risk (CVR) was predicted among ASCVD patients receiving stabilized LLT. For patients with LDL-C ≥ 70 mg/dl, the absolute LDL-C reduction required to achieve an LDL-C of < 70 or < 55 mg/dl (LDL-C of 69 or 54 mg/dl, respectively) was calculated. Relative and absolute risk reductions (RRRs and ARRs) were simulated. Results: Of the 2039 patients, 61% did not achieve LDL-C < 70 mg/dl. For patients with LDL-C ≥ 70 mg/dl, median (interquartile range) baseline LDL-C and 10-year CVR were 93 (81–115) mg/dl and 32% (25–43%), respectively. Median LDL-C reductions of 24 (12–46) and 39 (27–91) mg/dl were needed to achieve an LDL-C of 69 and 54 mg/dl, respectively. Attaining ACC/AHA or ESC/EAS goals resulted in simulated RRRs of 14% (7–25%) and 22% (15–32%), respectively, and ARRs of 4% (2–7%) and 6% (4–9%), respectively. Conclusion: In ASCVD patients, achieving ESC/EAS LDL-C goals could result in a 2% additional ARR over 10 years versus the ACC/AHA approach. Graphical abstract: [Figure not available: see fulltext.] © 2022, The Author(s).

Lifetime medication burden from current approaches to LDL-cholesterol (LDL-C) lowering is reliant on small molecules requiring daily dosing with the burden of responsibility placed upon patients. Patient-related factors (risk perception, health literacy) impact adherence and persistence. Adherence to statins and ezetimibe correlate with LDL-C reduction and risk, potentially accounting for approximately 12 000 avoidable cardiovascular events per 500 000 patients annually (1). Attempts to improve adherence have had mixed results with only textmessaging reminders, community health worker-based reinforcement and fixed-dose combination pills shown to be effective at improving adherence and clinical events (2). Patienttailored strategies combining multiple approaches including in-person consultations may yield better outcomes, but implementation is complex, consuming both time and resource. Obesity and smoking cessation have been tackled with monetary compensation. Technology offers scalable low-cost options for pill and refill reminders through the use of telephone calls, text-messages, and mobile apps. Finally, a crucial barrier to long-term adherence is the asymptomatic nature of cardiovascular risk factors which may impact medication adherence. This could be facilitated by simplifying access to prescriptions and refills, through electronic healthcare solutions that connect pharmacies to electronic patient records and enable automated prescriptions. Here we draw on population studies and therapeutic developments to potentially address the issue of adherence and lifetime exposure to LDL-C.

We study the relation between the set of n + 1 vertices of an n-simplex S having \(\mathbb {S}^{n-1}\) as circumsphere, and the set of n + 1 unit outward normals to the facets of S. These normals can in turn be interpreted as the vertices of another simplex \(\hat {S}\) that has \(\mathbb {S}^{n-1}\) as circumsphere. We consider the iterative application of the map that takes the simplex S to \(\hat {S}\), study its convergence properties, and in particular investigate its fixed points. We will also prove some statements about well-centered simplices in the above context.

Professors Ivo Babuška, Milan Práger, and Emil Vitásek are renowned experts in numerical analysis and computational methods. Their fruitful scientific careers started in Prague, at the Institute of Mathematics of the Czechoslovak Academy of Sciences (now Czech Academy of Sciences). They collaborated there on various projects including the computational analysis of the construction technology for Orlík Dam. In 1966 they published their joint book entitled Numerical Processes in Differential Equations. It is an honor for the Institute of Mathematics to host a conference on the occasion of their birthdays.

This paper is about 0/1-triangles, which are the simplest nontrivial examples of 0/1-polytopes: convex hulls of a subset of vertices of the unit n-cube In. We consider the subclasses of right 0/1-triangles, and acute 0/1-triangles, which only have acute angles. They can be explicitly counted and enumerated, also modulo the symmetries of In.

Cottle's proof that the minimal number of 0=1-simplices needed to triangulate the unit 4-cube equals 16 uses a modest amount of computer generated results. In this paper we remove the need for computer aid, using some lemmas that may be useful also in a broader context. One of the 0=1-simplices involved, the so-called antipodal simplex, has acute dihedral angles. We continue with the study of such acute binary simplices and point out their possible relation to the Hadamard determinant problem.

At the end of the 20th century, it was discovered that the expansion of the Universe is speeding up. This acceleration is attributed to dark energy, which seems to be distributed uniformly almost everywhere and thus essentially influences the Hubble parameter H = H(t) characterizing this expansion. In this book, the authors present current research in the study of the theory, implications and roles in cosmology of dark energy. Topics include gravitational aberration and the origin of dark energy; the role of dark energy in the evolution of the universe; the importance of supernova observations for exploring the nature of dark energy; and deformed quantum field theory, thermodynamics at low and high energies, and the dark energy problem. (Imprint: Nova)

In this work we present a survey of some geometric results on tetrahedral partitions and their refinements in a unified manner. They can be used for mesh generation and adaptivity in practical calculations by the finite element method (FEM), and also in theoretical finite element (FE) analysis.Special emphasis is laid on the correspondence between relevant results and terminology used in FE computations, and those established in the area of discrete and computational geometry (DCG).

We use laboratory experiments to investigate how employers develop social structures for sharing information about the trustworthiness of job candidates, when worker opportunism is possible. The experimental data show that substantial information sharing emerges. Two types of information networks are observed. One consists of 'anonymity networks' where information is anonymously and voluntarily provided as a collective good for all employers to use. The other type is a 'reciprocity network' where information sharing is driven by the rewarding of previously given information by the requestor. In both types, the extent of information sharing depends on the costs of providing it. Moreover, information sharing enables employers to recruit trustworthy workers which creates a high quality of trading, benefiting both employer and worker.

We study how the number of traders affects the interaction between a centralized exchange and bilateral negotiations in an experimental labor market with excess supply and incomplete contracts. In bilateral negotiations firms obtain information about employees’ performance in previous jobs. Though market forces put a downward pressure on wages in large markets, reciprocal tendencies do not differ. Hence, the occurrence of bilateral negotiations increases overall efficiency in both market sizes.

We study the process by which subordinated regions of a country can obtain a more favourable political status. In our theoretical model a dominant and a dominated region first interact through a voting process that can lead to different degrees of autonomy. If this process fails then both regions engage in a costly political conflict which can only lead to the maintenance of the initial subordination of the region in question or to its complete independence. In the subgame-perfect equilibrium the voting process leads to an intermediate arrangement acceptable for both parts. Hence, the costly political struggle never occurs. In contrast, in our experiments we observe a large amount of fighting involving high material losses, even in a case in which the possibilities for an arrangement without conflict are very salient.

Google vindt in een oogwenk de meest relevante web-bladzijden over een bepaald onderwerp. Omdat het web uit zo'n tien miljard bladzijden bestaat is dit een enorm indrukwekkende prestatie: het lijkt eenvoudiger om een naald in een hooiberg te vinden. De kracht van Google schuilt in de mathematische omschrijving van het begrip belangrijkheid van een web-bladzijde: de zogenaamde PageRank. We zullen laten zien welke ideeen de studenten Page en Brin daar over hadden toen ze Google rond 1997 ontwikkelden. Uiteindelijk bedachten ze een wiskundige vergelijking waarvan de PageRank de oplossing is. We zullen deze PageRank-vergelijking afleiden uit een lijstje van begrijpelijke wensen over PageRank, en ons buigen over de vraag hoe Google deze vervolgens uitrekent. Overigens kunnen we deze vraag niet in zijn geheel beantwoorden: een aantal zaken rondom PageRank wordt door Google strict geheim gehouden. Het Google PageRank probleem wordt door velen gezien als de grootste (matrix-) berekening die ooit is ondernomen.

Google bewaart op zijn computers adressen en trefwoorden van tien miljard webpagina’s en iedere dag voegen z’n zoekrobots er weer miljoenen pagina’s aan toe. Hoe is het mogelijk, dat Google in deze berg informatie meestal precies de webpagina’s vindt die jij zoekt? Wiskundig gezien is het internet een ‘gerichte graaf’, en het Google PageRank-algoritme laat op die graaf elke maand een gigantische berekening los om alle pagina’s in een ranglijst te zetten. Jan Brandts, aan de Universiteit van Amsterdam specialist in lineaire algebra en matrixrekening, legt uit hoe het werkt.

This paper studies experimentally how the existence of social information networks affects the ways in which firms recruit new personnel. Through such networks firms learn about prospective employees' performance in previous jobs. Assuming individualistic preferences social networks are predicted not to affect overall labor market behavior, while with social preferences the prediction is that when bilaterally negotiated: (i) wages will be higher and (ii) that workers in jobs with incomplete contracts will respond with higher effort. Our experimental results are consistent with the social preferences view, both for the case of excess demand and excess supply of labor. In particular, the presence of information networks leads to more efficient allocations.

We outline a solution method for mixed finite element discretizations based on dissecting the problem into three separate steps. The first handles the inho- mogeneous constraint, the second solves the flux variable from the homogeneous problem, whereas the third step, adjoint to the first, finally gives the Lagrangian multiplier. We concentrate on aspects involved in the first and third step mainly, and advertise a multi-level method that allows for a stable computation of the intermediate and final quantities in optimal computational complexity.

Everybody who has some experience in doing mathematics knows that di mensional reduction and projection are useful tools to confront problems that are too complicated to solve without any simplication Who hasnt occasion ally but notwithstanding timidly suggested that perhaps it would be a good idea to study the simple onedimensional case rst before trying to understand the realworld threedimensional problem Apparently it is a widespread faith that such simplications will not damage the essential mathematical or physical truth that is hidden in the original problem But is this faith founded Re gardless of the answer one should realize that in many applications there is no plausible alternative so it would be unfair to judge too harshly on those who solve reduced problems and with due mathematical care formulate interesting and strong theorems and hypotheses on the full problem Among them are the people from the eld of numerical linear algebra