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Investigation of Chronological Thinking Skills of Secondary School Students and Development of These Skills Based on Grade Level
No full textThe aim of this study is to determine the chronological thinking skills
of secondary school students in the light of two approaches in the
literature and to reveal the role of age (grade level) in the
development of these skills. The study group of the research, which was
designed as a screening model, consisted of 102 students (52 girls and
50 males) who studied in a high school in the city centre of Ankara in
the academic year 2017-2018. The data of the study were obtained from
performance tasks, prepared in accordance with the learning outcomes in
the 2017 Curriculum of Secondary Education History Lesson (9th, 10th and
11th Grades) and Republic of Turkey Revolution History and Kemalism
Lesson, with the aim of acquiring chronological thinking skills present
in the curricula mentioned. The performance tasks included activities
for six sub-dimensions of chronological thinking. The performance tasks
were evaluated through a graded scoring key (rubric) by the history
teacher who gave the lessons to the students in the study group and a
faculty member apart from the researcher himself. According to the
results of the study, the chronological thinking skills of the students
at the 9th, 10th, 11th and 12th grades of the secondary education and
aged between 15-18 continue to develop depending on the grade level.
This situation supports the ideas of child-centred thinkers in the
teaching of the concept of historical time. In addition, the students in
the study group have low skill levels also in six sub-dimensions of
chronological thinking. This is more evident in the sub-dimensions of
chronological thinking skills that require students to produce written
or visual products. This result supports the idea that learning-teaching
environments, as well as age-related development, are determinant in the
teaching of historical time concept and related skills, and reveals that
historical time and related skills cannot be acquired sufficiently in
history lessons in secondary education level in our country
Spectral properties of non-selfadjoint Sturm-Liouville operator equation on the real axis
No full textIn this paper, we analyze the non-selfadjoint Sturm-Liouville operator L
defined in the Hilbert space L-2(R, H) of vector-valued functions which
are strongly-measurable and square-integrable in R. L is defined
L(y) = -y `' + Q(x) y, x is an element of R,
for every y is an element of L-2(R, H) where the potential Q(x) is a
non-selfadjoint, completely continuous operator in a separable Hilbert
space H for each x is an element of R. We obtain the Jost solutions of
this operator and examine the analytic and asymptotic properties.
Moreover, we find the point spectrum and the spectral singularities of L
and also obtain the sufficient condition which assures the finiteness of
the eigenvalues and spectral singularities of L
A New Nonparametric Test for Testing Equality of Locations Against Umbrella Alternatives
No full text
Gliserinden Elektrokimyasal Yeniden Yapılandırma Yöntemiyle Hidrojen Üretimine Farklı Parametrelerin Etkisi
No full textIron oxide-Si nanoparticle magnetic core-shell induced by the interaction of d-orbitals of Fe2+ with reconstructed Si dimer-like defects
No full textRedox-type charge exchange between Si nanoparticles and aqueous metal
ions m(x+) was recently used to synthesize core-shell nanocomposites in
which their functionalities have been integrated. The process requires
the electron (hole) affinities of the two to be different, with the
efficiency of the charge exchange being strongly dependent on their
difference. In this paper, we examine the interaction of Fe ions and red
luminescent Si nanoparticles where the metal ion has comparable electron
affinity to that of the Si nanoparticle. Scanning electron microscopy
and fluorescent spectroscopy imaging show the formation of red
luminescent core-shell clusters ranging from 100 nm to 500 nm. A
permanent magnet is found to pull the structures indicating the
formation of a magnetic phase. We use first principle atomistic
computations at the unrestricted Hartree-Fock-DFT (density functional
theory) level to obtain the charging energies and affinities of various
ions of Fe and the Si nanoparticle. The computations indicate that Fe2+
cannot be oxidized to Fe3+ by the nanoparticle and it cannot strip one
or two electrons from the nanoparticle and freely separate, resulting in
bound complexes. Our analysis shows that a magnetic phase of iron oxide
results from charge delocalization over the complex and a simultaneous
interaction of the iron d-orbitals with the oxygen's lone electrons and
the nanoparticle's reconstruction dimer-like defects. The core-shell
integration at the nanoscale affords double functionality of
luminescence and magnetism enhancing sensing, tracking, and delivery and
enabling a variety of applications, including controlled drug delivery,
underground oil and water exploration, and recovery
Sexual Health/Reproductive Health-Related Problems of Lesbian, Gay, Bisexual and Transgender People in Turkey and Their Health-Care Needs
No full textThe regression of endometriosis with glycosylated flavonoids isolated from Melilotus officinalis (L.) Pall. in an endometriosis rat model
No full textObjective: Melilotus officinalis (L.) Pall. is commonly used for
treating bronchitis, painful menstruation, hemorrhoids, kidney stones,
ulcers of the eyes, earache, and hardening and swelling of uterus. The
European Medicines Agency reported the use of M. officinalis orally
against stomach ache, gastric ulcer, and disorders of the liver and
uterus in folk medicine. The present study aimed to appraise the
activity of M. (L.) Pall. aerial parts in endometriosis rat model.
Materials and methods: The endometriosis rat model was used to evaluate
the potential activity of M. officinalis aerial parts based on its
folkloric usage. The aerial parts of M. officinalis were extracted with
n-hexane, ethyl acetate (EtOAc), and methanol (MeOH), respectively. The
adhesion scores, endometrial foci areas, and cytokine levels were
measured in all treated groups. After the biological activity studies,
phytochemical studies were performed on the active extract and the
fractions obtained from the active extract.
Results: The MeOH extract significantly decreased the endometrial foci
areas and cytokine levels in rats with endometriosis. Fractionation was
performed on the MeOH extract to achieve bioactive molecules. Following
the fractionation, the fractions obtained from the MeOH extract were
tested. Fraction C showed the highest activity in the rat endometriosis
model. Phytochemical investigation of the active fraction (Fraction C)
resulted in isolation and elucidation of some quercetin and kaempferol
glucoside derivatives.
Conclusion: Fraction C obtained from the MeOH extract of M. officinalis
showed the highest activity, yielding four glycosylated flavonoids. (C)
2020 Taiwan Association of Obstetrics \& Gynecology. Publishing services
by Elsevier B.V
