OALib Journal期刊

ISSN: 2333-9721



匹配条件: “Natalia;” ,找到相关结果约3437条。
Effect of Stacking Fault Energy on the Mechanism of Texture Formation during Alternating Bending of FCC Metals and Alloys  [PDF]
Natalia Shkatulyak
International Journal of Nonferrous Metallurgy (IJNM) , 2013, DOI: 10.4236/ijnm.2013.22005

Alternating bending shear stresses lead to the formation of twin orientations in the texture of FCC materials with middle and low stacking fault energy (SFE). Only in the stainless steel with a low SFE during alternating bending with different number of cycles components of shear texture {111}; {hkl}<110>; {001}<110> were formed. Copper (middle SFE), along with orientations of twinning and cubic texture formed orientation of deformation {135}<211>. During alternating bending of aluminum (high SFE), a dynamic recovery occurred. The share of initial cubic texture increases with the increase of number of cycles of alternating bending and reaches its maximum after three cycles. Share of component of texture Goss increased slightly. The most significant change of the microstructure and texture occurred during the first 3 - 5 cycles

Different behavior of protein B23/nucleophosmin and UBF in HeLa cells during apoptosis  [PDF]
Natalia M. Vladimirova, Natalia A. Potapenko
Journal of Biophysical Chemistry (JBPC) , 2011, DOI: 10.4236/jbpc.2011.24049
Abstract: The behavior of UBF (upstream binding factor) and nucleophosmin in HeLa and HeLa-Bcl-2 cells during apoptosis induced by TNF-α, emetine, and their mixture was investigated. A pronounced apoptosis was achieved only in HeLa cells treated with a mixture of the inducers. Immunoblotting analysis of UBF and nucleophosmin in samples containing different portions of cells with apoptotic nuclei was carried out. It showed that UBF was proteolytically cleaved giving a stable 76-kDa fragment. Increasing content of the fragment during apoptosis correlated with the level of cells containing apoptotic nuclei and with a decrease in the content of full-sized UBF. Determination of N- and C-terminal sequences of UBF and 76-kDa fragment allowed us not only to characterize UBF at the protein level, but also to describe the site of the apoptosis-specific proteolysis. Nucleophosmin did not undergo proteolytic cleavage during apoptosis and its content was unchanged even in a sample containing 100% of cells with apoptotic nuclei. However in cells reached terminal stages of apoptosis, the balance between mono- and oligomeric forms of nucleophosmin changed due to depletion of monomeric forms and appearance of two additional oligomeric forms with lower molecular weight.
The Digital Fingerprinting Method for Static Images Based on Weighted Hamming Metric and on Weighted Container Model  [PDF]
Sergey Bezzateev, Natalia Voloshina
Journal of Computer and Communications (JCC) , 2014, DOI: 10.4236/jcc.2014.29016

The algorithm of fingerprint constructing for still images based on weighted image structure model is proposed. The error correcting codes that are perfect in weighted Hamming metric are used as a base for fingerprint constructing.

Twin Reverse Arterial Perfusion (TRAP): Case Report  [PDF]
Natalia Adamou, Ibrahim Yakasai
Open Journal of Obstetrics and Gynecology (OJOG) , 2014, DOI: 10.4236/ojog.2014.416147
Abstract: The twin reversed arterial perfusion (TRAP) sequence is an anomaly unique to monochorionic multiple pregnancies. It is a rare complication. We present a case of acardius anephus, which was mistaken for a live anomalous singleton fetus. A 21-year-old unbooked Primigravida was seen in labour ward with a ten hours history of labour pains. Urgent transabdominal ultrasound revealed a singleton live fetus at 30 weeks gestation with gross cystic mass lesion at the level of the abdomen and polyhydramnious. Caesarean section confirms a twin gestation with monoamniotic monochorionic single placenta. The umbilical cord of the acardiac twin was short—First twin was a live female baby, weighing 1000 g. TRAP is a rare event an early referral to feto maternal unit will improve perinatal outcome.
Efficient Density Estimation and Value at Risk Using Fejér-Type Kernel Functions  [PDF]
Olga Kosta, Natalia Stepanova
Journal of Mathematical Finance (JMF) , 2015, DOI: 10.4236/jmf.2015.55040

This paper presents a nonparametric method for computing the Value at Risk (VaR) based on efficient density estimators with Fejér-type kernel functions and empirical bandwidths obtained from Fourier analysis techniques. The kernel-type estimator with a Fejér-type kernel was recently found to dominate all other known density estimators under the \"\"-risk, \"\". This theoretical finding is supported via simulations by comparing the quality of the density estimator in question with other fixed kernel estimators using the common \"\"-risk. Two data-driven bandwidth selection methods, cross-validation and the one based on the Fourier analysis of a kernel density estimator, are used and compared to the theoretical bandwidth. The proposed nonparametric method for computing the VaR is applied to two fictitious portfolios. The performance of the new VaR computation method is compared to the commonly used Gaussian and historical simulation methods using a standard back-test procedure. The obtained results show that the proposed VaR model provides more reliable estimates than the standard VaR models.

The effect of high fat food on erythrocyte phospholipids, fatty acids composition and glutathione redox-system of rats with alimentary dyslipidemia  [PDF]
Natalia V. Zhukova, Yulia K. Karaman, Natalia V. Zhukova
Health (Health) , 2010, DOI: 10.4236/health.2010.21008
Abstract: To evaluate the effects of high fat food consisted of tallow (19% of total diets) and cholesterol (2%) on modification of erythrocyte phospholipids, fatty acids composition and glutathione redox- system of male Wistar rats with alimentary dysli- pidemia. The results demonstrated that after 30 and 180 days of high-fat feed erythrocyte phos- phatidylinositol and phosphatidylcholine levels were reduced, phosphatidylserine were in-creased. Only on the 90 days of the experiment phosphatidylinositol level increased. In all grow- ups the erythrocyte 18:0 saturated fatty acids and 20:4n6, 22:4n6 polyunsaturated fatty acids (PUFA) were increased. Deficit of n3 PUFA- 20:5n3 and 22:6n3 after 90 and 180 days high fat feed promoted compensatory synthesis from 18:1n9 on 20:3n9. Erythrocyte maleic dialde-hyde increased, glutathione level decreased in all groups of rats after fed with high-fat feed. Glutathione reductase and glutathione peroxi-dase activity decreased in erythrocytes after 30 and 180 days of high-fat feed. In conclusion: high-fat diet during 30-90 days started adaptive answer in lipids of membrane and glutathione redox-system. Important mechanism of adapta-tion of a cellular membrane to high-fat diet is increase major, structuring a membrane phos-phatidylethanolamine and minor, most meta-bolic significant fractions phospholipids (phos- phatidylinositol), keeps homeostasis of 18:2n6 and 22:6n3, 20:3n9 compensatory synthesis, decrease in activity of processes lipid peroxi-dation, activation of enzymes of redox-system glutathione. But prolonging the high-fat feeding (180 days and more) formed failure compensa-tory processes (dysadaptation). It is a risk factor of developmening atherosclerosis, diabetes, steatogepatitis and other diseases.
Additive Protective Effects of Luteolin and Pyruvate against 6-Hydroxydopamine and 3-Hydroxykynurenine Induced Neurotoxicity in SH-SY5Y Cells  [PDF]
Natalia Wszelaki, Matthias F. Melzig
Pharmacology & Pharmacy (PP) , 2013, DOI: 10.4236/pp.2013.44053

Oxidative stress has been implicated as one of the causes in cell death in many neurodegenerative disorders. Due to antioxidative properties in vitro, the use of flavonoids and other polyphenolic compounds synthesised by plants are considered to be a promising strategy to prevent Alzheimer’s disease and Parkinsons’s disease. In the present study, we tested protective effects of some polyphenols and sodium pyruvate on 6-hydroxydopamine (6-OHDA), salsolinol and 3-hydroxykynurenine (3-HK) induced neurotoxicity in human neuroblastoma SH-SY5Y cells. We found that luteolin prevented from 6-OHDA and 3-HK induced cell viability reduction and that one of the mechanisms involved in the neuroprotective process was the ability to increase the level of cellular ATP. However, luteolin was ineffective against salsolinol-induced toxicity. Neither pre-treatment with flavonoids nor simultaneous addition had any protective effects on 6-OHDA, salsolinol or 3-HK induced neurotoxicity. Interestingly, both pre-treatment and co-treatment with pyruvate provided protection against 6-OHDA, salsolinol or 3-HK induced toxicity. Moreover, luteolin and sodium pyruvate, administered together, acted additively, so to achieve the same effect, lower concentrations were needed. The ability of luteolin and sodium pyruvate to reduce toxicity of 6-OHDA and 3-HK in SH-SY5Y cells may be related to two different neuroprotective mechanisms and the capability to penetrate into the cell.

Delayed Presentation of Patients with Gynaecological Malignancies in Kano, North-Western Nigeria  [PDF]
Natalia Adamou, Usman Aliyu Umar
Open Journal of Obstetrics and Gynecology (OJOG) , 2015, DOI: 10.4236/ojog.2015.56048
Abstract: The diagnosis and management of gynaecological cancers are still challenging in low- and middle-income countries. In patients with gynaecological malignancies delay at any point increases morbidity and mortality. This study evaluated the factors that may delay presentation, diagnosis and treatment of patients with malignant gynaecological cancers, and described the duration of each delay. It was a prospective cross-sectional study. A total number of 96 patients diagnosed to have gynaecological malignancy were enrolled in the study between the April 2014 and April 2015. The median age was 47.5 years (range of 18 - 84 years). The diagnoses on admission were cervical malignancy 34 (35.42%), ovarian malignancy 32 (33.33%), chorio carcinoma 15 (15.63%), cancers of uterine body (endometrial and leiomyosarcoma) 10 (10.42%) and vulval malignancies 5 (5.2%). Majority of the patients 65 (67.7%) presented late at either stage III or IV. At presentation, 36 patients (37.5%) had severe anaemia; 10 patients (10.41%) had obstructive uropathy; 3 (3.13%) developed fistula; 19 (19.79%) died on admission from complication of their disease. Most patients 61 (63.54%) had delayed presentation of more than 90 days (“patients delay”). Time in decision ranged between 3 days to maximum of 2920 days and median of 150 days. 58 (60.42%) gave a reason for such delay as lack of knowledge of their presenting symptoms, as a warning sign of possible malignancy; 80 (83.33%) had delay in diagnosis (“doctor delay”); 40 (41.67%) reported that the medical practitioner did not make referral to the center with available gynaecological services; “hospital delay” was observed in 66 (68.75%) of patients. The reason for delayed treatment in 35 (36.46%) of patients was severe patients condition that warrant stabilization (blood transfusion and dialysis) and 29 (30.21%) could not afford the treatment. Late presentation is a great problem in the management of oncological patients in this environment. High cost of care is the major challenge for the patients and gynaecologist in north-western part of Nigeria.
Symbolism, solitude and modernity: science and scientists in porfirian Mexico
Priego, Natalia;
História, Ciências, Saúde-Manguinhos , 2008, DOI: 10.1590/S0104-59702008000200016
Abstract: the quest of mexico for a distinctive national identity throughout the 19th century reached a climax during the period known as the porfiriato, one of the principal features of which was the deep desire of porfirio díaz and his circle to turn mexico into a 'modern' country perhaps without a clear definition of the meaning of this concept. the debate about national identity had addressed such issues as the rejection of indigenous cultures, blind passion for french culture, and how to go about criating a modern nation by means of industrialization and scientific modernization. the concept of nation in mexico is definitively linked with the search for a national 'i', and with the struggle to overcome the solitude identified by octavio paz. paradoxically, this very quest forms a part of this identity, and it seems to remain inconclusive.
La escuela francesa de la regulación: Una revisión crítica
Visi?3n de futuro , 2010,
Abstract: the french regulation school sets out to carry out an analysis of capitalism and its transformations, with the purpose of understanding the periods of stable growth and the moments of structural change. the object of this paper consists of carrying out a critical revision of the contributions of this school, concentrating on the conceptual framework that it has developed. for this, in the first place the influences that marked the regulation approach will be reviewed, with special attention on its recovery from the marxist tradition. secondly, the ontological and methodological differences between the regulation approach and the neoclassic economy theory will be highlighted. thirdly, the fundamental concepts of the regulation school will be examined. in fourth place, it will be seen how, from these concepts, the crisis at the beginning of the 1970s was interpreted. in fifth place, how the regulation approach is thought as to the relation between economy and policy. in sixth place, the question of the international dimension will be examined. finally, the main objections that have been presented to the regulation approach, will be shown and will be evaluated critically.

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