Publications by authors named "Milan Cirkovic"

We present the case of a 49-year-old female of Caucasian European descent with chest tightness, fatigue, and palpitations, ultimately diagnosed with primary intracardiac angiosarcoma. Initial echocardiography revealed a significant mass within the right atrium, infiltrating the free wall. Surgical intervention included tumor excision and partial resection of the superior vena cava.

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Now that we know that Earth-like planets are ubiquitous in the universe, as well as that most of them are much older than the Earth, it is justified to ask to what extent evolutionary outcomes on other such planets are similar, or indeed commensurable, to the outcomes we perceive around us. In order to assess the degree of specialty or mediocrity of our trajectory of biospheric evolution, we need to take into account recent advances in theoretical astrobiology, in particular (i) establishing the history of habitable planets' formation in the Galaxy, and (ii) understanding the crucial importance of "Gaian" feedback loops and temporal windows for the interaction of early life with its physical environment. Hereby we consider an alternative macroevolutionary pathway that may result in tight functional integration of all sub-planetary ecosystems, eventually giving rise to a true superorganism at the biospheric level.

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In a recent article in this journal, Lingam and Loeb developed an excellent heuristic for searches for biosignatures versus technosignatures. We consider two ways in which their approach could be extended and sharpened, with focus on durability of technosignatures. We also note an important consequence of the adopted heuristic that offers strong support to the ideas of the Dysonian Search for ExtraTerrestrial Intelligence (SETI).

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Symmetry-based explanations using symmetry breaking (SB) as the key explanatory tool have complemented and replaced traditional causal explanations in various domains of physics. The process of spontaneous SB is now a mainstay of contemporary explanatory accounts of large chunks of condensed-matter physics, quantum field theory, nonlinear dynamics, cosmology, and other disciplines. A wide range of empirical research into various phenomena related to symmetries and SB across biological scales has accumulated as well.

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Jared Diamond's argument against extraterrestrial intelligence from evolutionary contingency is subjected to critical scrutiny. As with the earlier arguments of George Gaylord Simpson, it contains critical loopholes that lead to its unraveling. From the point of view of the contemporary debates about biological evolution, perhaps the most contentious aspect of such arguments is their atemporal and gradualist usage of the space of all possible biological forms (morphospace).

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Objective: Most difficult and very frequent complications of osteoporosis are vertebral compression fractures (VCF). Bone scintigraphy with Tc-phosphonates enables early detection of vertebral compression fractures in the first 72 hours of occuring. Typical scintigraphic findings is markedly increased radiotracer uptake in the linear pattern, throughout collapsed vertebral body.

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There are manifold intriguing issues located within largely unexplored borderlands of bioethics, future studies (including global risk analysis), and astrobiology. Human enhancement has for quite some time been among the foci of bioethical debates, but the same cannot be said about its global, transgenerational, and even cosmological consequences. In recent years, discussions of posthuman and, in general terms, postbiological civilization(s) have slowly gained a measure of academic respect, in parallel with the renewed interest in the entire field of future studies and the great strides made in understanding of the origin and evolution of life and intelligence in their widest, cosmic context.

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Physical processes that characterize living matter are qualitatively distinct in that they involve encoding and transfer of specific types of information. Such information plays an active part in the control of events that are ultimately linked to the capacity of the system to persist and multiply. This algorithmicity of life is a key prerequisite for its Darwinian evolution, driven by natural selection acting upon stochastically arising variations of the encoded information.

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Ought we to take seriously large risks predicted by "exotic" or improbable theories? We routinely assess risks on the basis or either common sense, or some developed theoretical framework based on the best available scientific explanations. Recently, there has been a substantial increase of interest in the low-probability "failure modes" of well-established theories, which can involve global catastrophic risks. However, here I wish to discuss a partially antithetical situation: alternative, low-probability ("small") scientific theories predicting catastrophic outcomes with large probability.

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The search for extraterrestrial life and intelligence constitutes one of the major endeavors in science, but has yet been quantitatively modeled only rarely and in a cursory and superficial fashion. We argue that probabilistic cellular automata (PCA) represent the best quantitative framework for modeling the astrobiological history of the Milky Way and its Galactic Habitable Zone. The relevant astrobiological parameters are to be modeled as the elements of the input probability matrix for the PCA kernel.

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Objectives: This study compared the anti-inflammatory effects of methylprednisolone (MP) and atorvastatin and analysed their influences on clinical variables in patients undergoing coronary revascularization.

Methods: Ninety patients with compromised left ventricular ejection fraction (≤30%) undergoing elective coronary surgery were equally randomized to one of three groups: statin group, treatment with atorvastatin (20 mg/day) 3 weeks before surgery; methylprednisolone group, a single shot of methylpredniosolone (10mg/kg); and control group.

Results: Postoperative IL-6 was higher in the control group when compared to the methylprednisolone and statin groups (p<0.

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We describe a significant practical consequence of taking anthropic biases into account in deriving predictions for rare stochastic catastrophic events. The risks associated with catastrophes such as asteroidal/cometary impacts, supervolcanic episodes, and explosions of supernovae/gamma-ray bursts are based on their observed frequencies. As a result, the frequencies of catastrophes that destroy or are otherwise incompatible with the existence of observers are systematically underestimated.

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A new strategy by which to defeat Carter's "anthropic" argument against extraterrestrial life and intelligence is presented. Our approach is based on relaxing hidden uniformitarian assumptions and considering instead a dynamical succession of evolutionary regimes governed by both global (Galaxy-wide) and local (planet- or planetary system-limited) regulation mechanisms. Notably, our increased understanding of the nature of supernovae, gamma-ray bursts, and strong coupling between the Solar System and the Galaxy, and the theories of "punctuated equilibria" and "macroevolutionary regimes" are in full accordance with the regulation-mechanism picture.

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Can astrophysics explain Fermi's paradox or the "Great Silence" problem? If available, such explanation would be advantageous over most of those suggested in literature which rely on unverifiable cultural and/or sociological assumptions. We suggest, instead, a general astrobiological paradigm which might offer a physical and empirically testable paradox resolution. Based on the idea of James Annis, we develop a model of an astrobiological phase transition of the Milky Way, based on the concept of the global regulation mechanism(s).

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Composite conduit aortic root replacement has become widely accepted as the preferred treatment for ascending aorta aneurysm and dissection. We present a patient in whom creation of 'buttons' was impossible due to fragility of the ascending aorta wall. The distal anastomosis was made to the transected aorta.

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Introduction: Nowadays, coronary-coronary bypass grafting (CCBG) has been applied in patients with heavily calcified ascending aorta or due to lack of graft material.

Case Report: We describe a case in which the patient's large left anterior descending (LAD) coronary artery, running well over the cardiac apex, presented with proximal and distal stenosis. Although the pedicled left internal thoracic artery (ITA) graft is sometimes too short for sequential bypass in cases of distal stenosis of the LAD coronary artery, we used a free, short segment of the pedicled left ITA for coronary-coronary bypass grafting.

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Radial artery segment has been used as a coronary-coronary graft for single, distal lesion of the large left anterior descending coronary artery running well over the cardiac apex. In our opinion this technique may occasionally be an attractive approach for bypassing very distal lesions of large coronary arteries combined with regular arterial or venous grafting of the target artery if proximal stenosis is also present. The remnant of the radial artery can be used for grafting of another diseased artery (eg, the large first marginal branch of the circumflex artery in our case report).

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