On the Complexity of Making a Distinguished Vertex Minimum or Maximum Degree by Vertex Deletion

In this paper, we investigate the approximability of two node deletion problems. Given a vertex weighted graph $G=(V,E)$ and a specified, or "distinguished" vertex $p \in V$, MDD(min) is the problem of finding a minimum weight vertex set $S \subseteq V\setminus \{p\}$ such that $p$ becomes the minimum degree vertex in $G[V \setminus S]$; and MDD(max) is the problem of finding a minimum weight vertex set $S \subseteq V\setminus \{p\}$ such that $p$ becomes the maximum degree vertex in $G[V \setminus S]$. These are known $NP$-complete problems and have been studied from the parameterized complexity point of view in previous work. Here, we prove that for any $\epsilon > 0$, both the problems cannot be approximated within a factor $(1 - \epsilon)\log n$, unless $NP \subseteq DTIME(n^{\log\log n})$. We also show that for any $\epsilon > 0$, MDD(min) cannot be approximated within a factor $(1 -\epsilon)\log n$ on bipartite graphs, unless $NP \subseteq DTIME(n^{\log\log n})$, and that for any $\epsilon > 0$, MDD(max) cannot be approximated within a factor $(1/2 - \epsilon)\log n$ on bipartite graphs, unless $NP \subseteq DTIME(n^{\log\log n})$. We give an $O(\log n)$ factor approximation algorithm for MDD(max) on general graphs, provided the degree of $p$ is $O(\log n)$. We then show that if the degree of $p$ is $n-O(\log n)$, a similar result holds for MDD(min). We prove that MDD(max) is $APX$-complete on 3-regular unweighted graphs and provide an approximation algorithm with ratio $1.583$ when $G$ is a 3-regular unweighted graph. In addition, we show that MDD(min) can be solved in polynomial time when $G$ is a regular graph of constant degree.Comment: 16 pages, 4 figures, submitted to Elsevier's Journal of Discrete Algorithm

Structural differences in languages

The relevance of the investigated problem is caused by the fact that lexical antonymy of different structure languages, such as English and Tatar, was not the subject of a separate study. This research paper deals with the problem of antonymy and different classifications existing in non-related languages nowadays. The article considers antonyms-reversives as a subclass of directional opposition. The main aim of this paper is to depict the typological peculiarities of antonym-reversives formation based on genetically non-related English and Tatar languages. We set the task to identify antonyms-reversives of the given languages, define their semantics, determine the thematic groups of this type of antonyms, and compare the structural peculiarities of their formation.peer-reviewe

Metallurgical enterprise I.P. Osokina in the middle Urals

Дается характеристика развития хозяйства предпринимателя Осокина на протяжении XVIII – начала Х1Х веков. Показаны этапы его развития и дробления среди наследников.The authors give characteristic development of the economy of the en-trepreneur Osokin during XVIII - beginning of XIX centuries. They show the stages of its development and fragmentation among the heirs

Valuable agronomic traits of chufa (Cyperus esculentus L.) accessions from the VIR collection: methods of preparing nodules for long-term storage

Background. Chufa is one of the most promising rare oilseed crops. The issues of preserving and obtaining highquality seed material are very important. The development of long-term genebank storage techniques for chufa nodules is a pressing task.Materials and methods. We studied 18 chufa germplasm accessions of various origin. The field study was conducted in 2010–2012 under the environmental conditions of Krasnodar Territory, Russia. Protein and oil content was analyzed according to the guidelines on the methods of quality control and safety of bioactive food additives (R 4.1.1672-03…, 2004); vitamin E according to the guidelines on the methods of analyzing the quality and safety of food products (Skurikhin, Tutelyan, 1987); fatty acid composition in line with IUPAC (1979) and GOST R 512677-2006, using an IIRGCS chromatograph.Results and conclusions. The study of valuable agronomic characters in chufa accessions showed that the height of plants varied from 49 to 69 cm; the number of nodules per plant from 80 to 110 pcs; the weight of nodules per plant from 18 to 49 g; the weight of nodules per plot (1 m2 ) from 101 to 393 g. Their oil content varied from 13.1 to 21.06 g/100 g, and protein content from 6 to 10%. Chufa accessions contained large amount of vitamin E: 19.23 to 35.23 mg/100 g. The content of saturated fatty acids in chufa oil was 17.75 to 20.99%, monounsaturated fatty acids from 68.21 to 71.55%, and polyunsaturated fatty acids from 9.94 to 12.17%. A technique of preparing chufa nodules for long-term storage was developed. The optimal time to assess germination energy is four days, with 11 days for germination percentage. Storage of chufa nodules for three years at a temperature of +20°C causes a decrease in their germination by 15–16%. When stored under low positive (+4°C) or negative temperatures (–18°C and –196°C), their germination percentage remained unchanged

The role of social protection in formation of quality of work life

In this article the elements of social protection of population are considered from the standpoint of the formation and development of the quality of work life. The features of the social insurance in Russia today are investigated. In this work author's classification of forms and types of social insurance and also the characteristic of the main subjects of compulsory social insurance are presented. The item-response of current Russian social insurance system is presented. The authors offer the option of reforming the existing system of social insurance in the aspect of unemployment insurance management. © IDOSI Publications, 2013

Межполушарная асимметрия реакций на пространственные модуляции локальных зрительных признаков

Visual perception starts with a parallel spatial-frequency filtering. A visual scene is presented by a number of local indications in outputs of first-order filters. Their spatial association is the next important operation. It is the grouping of local indicators that underlies the transition to spatial vision. Recent research indicates that second-ordervisual filters perform this grouping. It is believed that the right hemisphere plays the leading role in spatial vision.The present study puts forward a hypothesis that this dominance can be formed even at the stage of the transition from a local to a global description of visual scenes. For this purpose the authors investigated interhemispheric asymmetry of potentials caused by functioning of second-order visual filters. These elements integrate the outputsof first-order filters and respond to spatial modulations of local visual indications. To solve this problem the authors recorded visual evoked potentials to a non-modulated texture and textures sinusoidally modulated in orientation, spatial frequency, and contrast. Next, they subtracted the response to the non-modulated texture from theresponse to the modulated texture. In result, each derivation received three different waves (d-waves): to the modulation of contrast, orientation, or spatial frequency. The comparison of d-waves in symmetric derivations revealed that its amplitude for all theused modulations is higher in the right hemisphere. Interhemispheric asymmetry to the modulation of orientation was most pronounced; it manifested itself better in occipital regions. The findings of the study showed the leading role of the right hemisphere in the processes of spatial association of local visual indications.Зрительное восприятие начинается с параллельной пространственно-частотной фильтрации. На выходах фильтров первого порядка зрительная сцена описывается набором локальных признаков. Следующая важная операция – их пространственное объединение. Именно группирование локальных признаков лежит в основе перехода к пространственному зрению. В последние годы получены факты, свидетельствующие о том, что такое группирование выполняется зрительными фильтрами второго порядка. Считается, что ведущую роль в пространственном зрении человека играет правое полушарие. В нашем исследовании проверяется гипотеза, согласно которой это доминирование может формироваться уже на стадии перехода от локального к глобальному описанию зрительной сцены. С этой целью исследуется межполушарная асимметрия потенциалов, обусловленных функционированием зрительных фильтров второго порядка. Эти элементы объединяют выходы фильтров первого порядка и реагируют на пространственные модуляции локальных зрительных признаков. Для решения поставленной задачи регистрировались зрительные вызванные потенциалы на немодулированную текстуру и текстуры, синусоидально модулированные по контрасту, ориентации или пространственной частоте. Затем из ответа на модулированную текстуру вычитался ответ на немодулированную текстуру. В результате в каждом отведении получали 3 разностные волны (d-волны): на модуляцию контраста, ориентации или пространственной частоты. Сравнение d-волн в симметричных отведениях выявило, что ее амплитуда при всех использованных модуляциях выше в правом полушарии. Обнаружено также, что межполушарная асимметрия наиболее выражена при модуляции ориентации и лучше проявляется в затылочных областях. Полученные результаты указывают на ведущую роль правого полушария в реализации процессов, связанных с пространственным объединением локальных зрительных признаков

Noncompetitive Immunochemical Determination of Ribonuclease Using Transition Metal Ions and the Effect of Catalytic Hydrogen Release

A noncompetitive variant of immunochemical ribonuclease (RNase) determination has been developed, involving the use of Co(II) as a label. A variety of approaches to labeling the immunological reagent with the metal have been assessed. In the variant proposed, catalytic hydrogen release is used as a means of detecting the label, the amount of which is proportional to the RNase concentration. Conditions making it possible to record catalytic hydrogen release currents have been determined. In the presence of RNase, the electrocatalytic effect is maximum at a concentration of Co(II) in ammoniac buffer equal to 2 × 10-4 M (pH 10.0). The dependence is linear in the RNase concentration range 2000-4 ng/ml (threshold concentration, 2 ng/ml)

Noncompetitive immunochemical determination of ribonuclease using transition metal ions and the effect of catalytic hydrogen release | Nekonkurentnoe immunokhimicheskoe opredelenie ribonukleazy s ispol'zovaniem ionov perekhodnykh metallov i éffekta kataliticheskogo vydeleniia vodoroda.

A noncompetitive variant of immunochemical ribonuclease (RNase) determination has been developed, involving the use of Co(II) as a label. A variety of approaches to labeling the immunological reagent with the metal have been assessed. In the variant proposed, catalytic hydrogen release was used as a means of detecting the label, the amount of which was proportional to RNase concentration. Conditions making it possible to record catalytic hydrogen release fluxes were determined. In the presence of RNase, the electrocatalytic effect was maximum at a concentration of Co(II) in the ammoniac buffer, equal to 2 x 10(-4) M (pH 10.0). The dependence was linear in the range 4-2000 ng/ml RNase concentrations (threshold concentration, 2 ng/ml)

Amperometric enzyme immunosensors for diagnosing certain infectious diseases

Amperometric enzyme immunosensors based on planar electrodes were developed for the rapid determination of some bacterial antigens. Conditions for the operation of analytical devices (matrix component, pH of the buffer solution, and the dilution of antibodies in the biosensing part of the sensor) were selected. The analytical characteristics of enzyme immunosensors (analytical ranges and determination limits) were estimated. The analytical devices were tested in determining pyogenic streptococcus and aurous staphylococcus antigens in the blood serum of patients suffering from infectious diseases. It was shown that the developed sensors can be used for diagnosing diseases caused by these microorganisms. © 2005 Pleiades Publishing, Inc

Determination of bacterial antigens using a multichannel immunoenzyme amperometric sensor

A procedure for the individual determination of the antigens of the conditionally pathogenic micro-organisms Streptococcus pyogenes and Staphylococcus aureus present in combination using a multichannel immunoenzyme amperometric sensor based on a screen-printed electrode was developed. Conditions for fabricating the biosensing part and for the operation of the sensor (the matrix component, the ratio between biocomponents, and the substrate concentration) were chosen. The determination limits of bacterial antigens obtained using the analytical device were equal to 5 × 10-9 mg/mL. It was found that bacterial antigens simultaneously present in serums from patients can be determined using the sensor developed. © Pleiades Publishing, Inc., 2006