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Bounds For Spectral Radıus Usıng Graph Powers
No full textBu tez beş bölümden oluşmaktadır. Birinci bölüm giriş kısmından oluşmaktadır. İkinci bölümde grafın temel kavram ve özellikleri ile bazı özel graflar ve matrislerinden bahsedilmiştir. Üçüncü bölümde, sonlu, yönsüz, basit, bağlantılı grafların k. kuvveti ile ilgili literatürde var olan bazı tanım, teorem ve önermeler verilmiştir. Dördüncü bölümde ise sonlu, yönsüz, basit, bağlantılı grafların komşuluk matrisinin en büyük özdeğeri için bazı sınırlar elde edilmiştir. Beşinci bölüm sonuç kısmından oluşmaktadırThis thesis consists of five chapters. The first part consists of an introduction. In the second part, the basic concepts and properties of graph and some special graphs and matrices are mentioned. In the third part, some definition, theorems and lemmas exist in the literature about the -th power of finite undirected simple connected graphs are given. In the fourth chapter, some bounds are obtained for the largest eigenvalue of the adjacency matrix of finite undirected simple connected graphs. The fifth section consists of the conclusion part.
Science Cod
Cholinesterase and tyrosinase inhibitory potential and antioxidant capacity of lysimachia verticillaris L. And isolation of the major compounds [Lysimachia verticillaris L.’nin kolinesteraz ve tirozinaz inhibitör etki potansiyeli ve antioksidan kapasitesi ile ana bileşiklerinin izolasyonu]
No full textA review of the chip breaking methods for continuous chips in turning
No full textThe reliability of continuous turning process is a significant necessity
of mass production and automatic manufacturing systems. Long chips are
the main problems for the continuous turning operations and chip break
is difficult during the machining of ductile steel and superalloys. Chip
formation during machining negatively affects worker and tool safety,
workpiece quality, tool life, and energy consumption while also reducing
operational efficiency. To alleviate such problems, continuous chips
formation during machining must be controlled through chip breaking. As
part of this study, various chip breaker designs and approaches to chip
breaking were evaluated. The study analyzes the problems associated with
continuous chips and compiles knowledge of the mechanics involved in,
and the methods developed to handle chip breaking. The methods for
breaking continuous chips were categorized into five sections. Different
methods were contrasted against each other, the pros and cons were
presented and the results were given in a comparative table
Prognostic factors for short-term patient mortality following interhospital transfers
No full textIntroduction: The data on short-term mortality among patients following
interhospital transfers remain uncertain in the literature, and
particularly in Turkey. The aim of this study was to determine the
characteristics of interhospital transfer patients and to investigate
the factors associated with 72-h mortality. Methods: All interhospital
transfer patients aged 16 years and above from a secondary care public
hospital were evaluated retrospectively for the period January to
December 2018. A total of 34 variables, including age, gender, date of
transfer, referring unit, diagnosis, reason for transfer, transfer
destination, waiting and transfer time, vitals, the Glasgow Coma Scale,
the presence of intubation, cardiopulmonary resuscitation before
transfer, and the use of vasopressor medication, were included in the
univariate analysis. The factors associated with short-term mortality
were identified by multivariate regression analysis. Results: During the
1-year study period, 1216 interhospital transfers were performed. A
total of 116 (9.5\%) patients died within 72 h following interhospital
transfer. Among all the transfers, the median age was 62 (interquartile
range, 39-76) years. According to the multivariate analysis, vasopressor
use (odds ratio, 3.55; 95\% confidence interval: 1.32-9.52), age (odds
ratio, 1.01; 95\% confidence interval: 1.00-1.03), pulse (odds ratio,
1.01; 95\% confidence interval: 1.00-1.02), and diastolic blood pressure
(odds ratio, 0.97; 95\% confidence interval: 0.95-0.99) were predictive
of 72-h mortality following interhospital transfer. Conclusion: Nearly
10\% of all the transfers from the secondary care public hospital
resulted in mortality within 72 h. Vasopressor use, advanced age, lower
diastolic blood pressure, and tachycardia were the most important
factors associated with short-term mortality
On Ulam’s type stability criteria for fractional integral equations including Hadamard type singular kernel
No full textSurface enhanced Raman spectroscopy as a novel tool for rapid quantification of heroin and metabolites in saliva
No full textSynthesis and spectroscopic properties of (N/O) mono- and dispirocyclotriphosphazene derivatives with benzyl pendant arms: study of biological activity
No full textThe Cl replacement reactions of hexachlorocyclotriphosphazene (trimer;
N3P3Cl6) with sodium (N-benzyl)aminopropanoxides (1 and 2) produced
monospiro- (3 and 4), cis-, and trans-dispirocyclotriphosphazenes
(13-16). The monospiro tetrakis-aminocyclotriphosphazenes (5-12) were
obtained by the Cl substitutions of 3 and 4 with different secondary
amines. The cis- (13 and 14) and trans-dispirophosphazenes (15 and 16)
possessed 2 chiral P centers, and they were able to present meso and
racemic forms, respectively. Moreover, the structures of compounds 5 and
14 were designated using X-ray data. The absolute configuration of
compound 14 was found as SR in the solid state. Analytical and
spectroscopic data of the phosphazenes were consistent with their
suggested structures. Antimicrobial activities of the
benzyl-pendant-armed cyclotriphosphazenes were scrutinized against G(+)
and G(-) bacteria and yeast strains. The bacterium most affected by the
synthesized compounds was Pseudomonas aeruginosa. Minimum inhibitory
concentrations and minimal bacterial concentrations were in the range of
125-500 mu M. Interactions between the phosphazenes (3-12 and 15) and
plasmid DNA were studied with agarose gel electrophoresis. The
phosphazeneDNA interaction studies of the cyclotriphosphazenes revealed
that phosphazenes 3, 4, and 15 had a substantial effect on supercoiled
DNA by cleavage of the double helix
