Quaternionic factorization of the Schroedinger operator and its applications to some first order systems of mathematical physics

We consider the following first order systems of mathematical physics. 1.The Dirac equation with scalar potential. 2.The Dirac equation with electric potential. 3.The Dirac equation with pseudoscalar potential. 4.The system describing non-linear force free magnetic fields or Beltrami fields with nonconstant proportionality factor. 5.The Maxwell equations for slowly changing media. 6.The static Maxwell system. We show that all this variety of first order systems reduces to a single quaternionic equation the analysis of which in its turn reduces to the solution of a Schroedinger equation with biquaternionic potential. In some important situations the biquaternionic potential can be diagonalized and converted into scalar potentials

Current antiretroviral therapy: A review

The article presents an overview of clinical recommendations for currant antiretroviral therapy. Currently, the current preferred first-line antiretroviral therapy regimens are combinations of 2 or 3 antiretroviral drugs (ARVs) in one tablet with a frequency of administration 1 time per day and, as a rule, include drugs of the 2nd generation (integrase inhibitors or non-nucleoside reverse transcriptase inhibitors). These schemes have high efficiency and a good genetic barrier in the development of HIV resistance mutations. HIV protease inhibitors are used as alternative regimens. Schemes with the least number and spectrum of side effects, no effect on metabolic processes and minimal drug interactions have advantages. Switching patients to injectable therapy regimens with a frequency of administration of drugs once every 2 months can significantly improve the quality of life of patients and, accordingly, adherence to their treatment. The development and introduction of new classes of ARVs into clinical practice ensures the suppression of HIV replication in most patients with HIV strains resistant to drugs of the main groups of ARVs (nucleoside/nucleotide reverse transcriptas

Cybersecurity of the network perimeter of the critical information infrastructure object

The purpose of this paper is an analytical pre-project study of possible technological aspects of countering external computer attacks on critical network infrastructure. This will make it possible to specify the tasks for further resolving this problem in the aspect of developing the necessary software and hardware. The practical implementation of such tasks is an urgent and rather unconventional problem due to various factors of change in the classical concept of the network perimeter as a physical boundary of the information infrastructure, which becomes virtual and, therefore, requires the use of new approaches to the development of technical solutions. Based on statistical data on the number and quality of computer incidents, the study provides a justification for the relevance of the above problem, and gives an overview of widely used technical means for protecting the classic network perimeter, such as firewalls and systems for detecting attacks and intrusions. A comparative analysis of modern technological trends in their development, referred to in publications as «Threat Detection and Response», «Extended Detection and Response», is carried out. However, despite the powerful software and hardware functionality of these solutions, their common drawback is indicated as the lack of adequate counteraction to computer attacks with a remote mode of the user work. In this regard, the latest concept of virtual network perimeter protection, referred to by the authors as «Cybersecurity Mesh» («cybersecurity network»), is detailed. It is this methodology that seems to be the most promising for the development of appropriate technological solutions to ensure the cybersecurity of the perimeter of the critical information infrastructure. The paper might be useful to specialists working on the security of critical information infrastructure facilities, as well as to employees of educational classes in the implementation of appropriate training, retraining and advanced training programs for such specialists

Technological platform for the implementation of the cybersecurity network concept ("Cybersecurity Mesh")

An analytical review of methods and modern means of countering computer attacks on distributed information infrastructure shows that one of the promising solutions to this problem is the practical implementation of the concept of "Cybersecurity Mesh" (cybersecurity networks"). It involves the application of such an approach that will eliminate specific threats associated with the actual "blurring" of the physical boundaries of the corporate information system by switching to point protection of any remote object. To provide the necessary functionality for such a reliable and secure connection of critical information infrastructure (CII) objects, it is proposed to use a single cloud platform combining several well-known and already used solutions as the technological basis of a cybersecurity network. These include: 5G standard mobile communications, Secure Access Border Service (SASE) and Advanced Detection and Response Service (XDR). This paper analyzes the features of these main elements of such a platform in relation to the implementation of the concept of a distributed CII cybersecurity network in terms of the implementation of its functionality. Further, the issues of the necessary software restructuring of the corporate segment of the Internet in the conditions of the impossibility of full control of its physical infrastructure are considered. Such a task is solved by creating an appropriate cyber level on top of the traditional Internet infrastructure, technologically implemented on the basis of its three main components: cyber control, cyber node and trust node. Functional requirements for these components are described in detail, as well as technological modular solutions for the transition to point protection of each CII object. The obtained results of the conducted research can become a methodological basis for the transition to the design stage of a specific corporate cybersecurity network after the mandatory feasibility study based on risk analysis, since the practical implementation of the analyzed proposals is a complex and expensive process, especially if the necessary restructuring of existing network security systems

Comparison of Spider-Robot Information Models

The paper deduces a mathematical model of a spider-robot with six three-link limbs. Many limbs with a multi-link structure greatly complicate the process of synthesizing a model, since in total the robot has twenty-four degrees of freedom, i.e., three coordinates of the center of mass of the body in space, three angles of rotation of the body relative to its center of mass and three degrees of freedom for each limb, to describe the position of the links. The derived mathematical model is based on the Lagrange equations with a further transformation of the equations to the Cauchy normal form in a matrix form. To test the resulting model in a SimInTech environment, an information model is synthesized and two simple experiments ar carried out to simulate the behavior of real spiders: moving forward in a straight line and turning in place at a given angle. The experimental results demonstrate that the synthesized information model can well cope with the tasks and the mathematical model underlying it can be used for further research

Penilaian Kinerja Keuangan Koperasi di Kabupaten Pelalawan

This paper describe development and financial performance of cooperative in District Pelalawan among 2007 - 2008. Studies on primary and secondary cooperative in 12 sub-districts. Method in this stady use performance measuring of productivity, efficiency, growth, liquidity, and solvability of cooperative. Productivity of cooperative in Pelalawan was highly but efficiency still low. Profit and income were highly, even liquidity of cooperative very high, and solvability was good

Juxtaposing BTE and ATE – on the role of the European insurance industry in funding civil litigation

One of the ways in which legal services are financed, and indeed shaped, is through private insurance arrangement. Two contrasting types of legal expenses insurance contracts (LEI) seem to dominate in Europe: before the event (BTE) and after the event (ATE) legal expenses insurance. Notwithstanding institutional differences between different legal systems, BTE and ATE insurance arrangements may be instrumental if government policy is geared towards strengthening a market-oriented system of financing access to justice for individuals and business. At the same time, emphasizing the role of a private industry as a keeper of the gates to justice raises issues of accountability and transparency, not readily reconcilable with demands of competition. Moreover, multiple actors (clients, lawyers, courts, insurers) are involved, causing behavioural dynamics which are not easily predicted or influenced. Against this background, this paper looks into BTE and ATE arrangements by analysing the particularities of BTE and ATE arrangements currently available in some European jurisdictions and by painting a picture of their respective markets and legal contexts. This allows for some reflection on the performance of BTE and ATE providers as both financiers and keepers. Two issues emerge from the analysis that are worthy of some further reflection. Firstly, there is the problematic long-term sustainability of some ATE products. Secondly, the challenges faced by policymakers that would like to nudge consumers into voluntarily taking out BTE LEI

Severe early onset preeclampsia: short and long term clinical, psychosocial and biochemical aspects

Preeclampsia is a pregnancy specific disorder commonly defined as de novo hypertension and proteinuria after 20 weeks gestational age. It occurs in approximately 3-5% of pregnancies and it is still a major cause of both foetal and maternal morbidity and mortality worldwide1. As extensive research has not yet elucidated the aetiology of preeclampsia, there are no rational preventive or therapeutic interventions available. The only rational treatment is delivery, which benefits the mother but is not in the interest of the foetus, if remote from term. Early onset preeclampsia (<32 weeks’ gestational age) occurs in less than 1% of pregnancies. It is, however often associated with maternal morbidity as the risk of progression to severe maternal disease is inversely related with gestational age at onset2. Resulting prematurity is therefore the main cause of neonatal mortality and morbidity in patients with severe preeclampsia3. Although the discussion is ongoing, perinatal survival is suggested to be increased in patients with preterm preeclampsia by expectant, non-interventional management. This temporising treatment option to lengthen pregnancy includes the use of antihypertensive medication to control hypertension, magnesium sulphate to prevent eclampsia and corticosteroids to enhance foetal lung maturity4. With optimal maternal haemodynamic status and reassuring foetal condition this results on average in an extension of 2 weeks. Prolongation of these pregnancies is a great challenge for clinicians to balance between potential maternal risks on one the eve hand and possible foetal benefits on the other. Clinical controversies regarding prolongation of preterm preeclamptic pregnancies still exist – also taking into account that preeclampsia is the leading cause of maternal mortality in the Netherlands5 - a debate which is even more pronounced in very preterm pregnancies with questionable foetal viability6-9. Do maternal risks of prolongation of these very early pregnancies outweigh the chances of neonatal survival? Counselling of women with very early onset preeclampsia not only comprises of knowledge of the outcome of those particular pregnancies, but also knowledge of outcomes of future pregnancies of these women is of major clinical importance. This thesis opens with a review of the literature on identifiable risk factors of preeclampsia

Search for stop and higgsino production using diphoton Higgs boson decays

Results are presented of a search for a "natural" supersymmetry scenario with gauge mediated symmetry breaking. It is assumed that only the supersymmetric partners of the top-quark (stop) and the Higgs boson (higgsino) are accessible. Events are examined in which there are two photons forming a Higgs boson candidate, and at least two b-quark jets. In 19.7 inverse femtobarns of proton-proton collision data at sqrt(s) = 8 TeV, recorded in the CMS experiment, no evidence of a signal is found and lower limits at the 95% confidence level are set, excluding the stop mass below 360 to 410 GeV, depending on the higgsino mass

Differential cross section measurements for the production of a W boson in association with jets in proton–proton collisions at √s = 7 TeV

Measurements are reported of differential cross sections for the production of a W boson, which decays into a muon and a neutrino, in association with jets, as a function of several variables, including the transverse momenta (pT) and pseudorapidities of the four leading jets, the scalar sum of jet transverse momenta (HT), and the difference in azimuthal angle between the directions of each jet and the muon. The data sample of pp collisions at a centre-of-mass energy of 7 TeV was collected with the CMS detector at the LHC and corresponds to an integrated luminosity of 5.0 fb[superscript −1]. The measured cross sections are compared to predictions from Monte Carlo generators, MadGraph + pythia and sherpa, and to next-to-leading-order calculations from BlackHat + sherpa. The differential cross sections are found to be in agreement with the predictions, apart from the pT distributions of the leading jets at high pT values, the distributions of the HT at high-HT and low jet multiplicity, and the distribution of the difference in azimuthal angle between the leading jet and the muon at low values.United States. Dept. of EnergyNational Science Foundation (U.S.)Alfred P. Sloan Foundatio