scholarly journals Nutrition issues

2021 ◽  
Vol 32 (8-9) ◽  
pp. 778-779
Author(s):  
A. K.

For the first time, the Moscow Institute of Public Catering publishes a scientific journal on its own. The organization of such a journal makes it possible to print scientific and practical articles not only of a strictly scientific order, but also of a practical one, solving the problems of today.

2018 ◽  
Vol 17 (3) ◽  
pp. 364-366
Author(s):  
Muhammet Usak

Science Education is a multidisciplinary field of study with roots about three centuries ago. Researches in this field were published for the first time in a scientific journal with School Science and Mathematics, which started in 1901. The number of scientific journals in Science Education has increased in parallel with the increase in the number of related research. The published literature is sometimes about trending topics. In some other cases, they offer novelty and new paradigms. Last 50 years of Science Education are shaped by various topics. Hence, these different issues are being published in scientific journals. At the end of the 70s, studies on constructivism, meaningful learning, misconception, conceptual learning (Driver, & Easley, 1978; Driver, 1983; Driver, & Oldham, 1986; von Glasersfeld, 1984; Ausubel, Novak, & Hanesian, 1978; Novak, 1979 & 1990, Novak, & Gowin, 1984; Novak, & Musonda, 1991) began to come forward. Conferences are being held especially on misconception. Many articles have been published and continue to be published on the topic. Starting with the second half of 80s, studies on PCK, which were first described by Shulman, began to surface in science education journals in the field of teacher training (Shulman, 1986; Usak, 2009, Usak, Ozden, & Eilks, 2011; Usak, Ozden, & Saglam, 2011).


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Ilda Fontes ◽  
Letícia Fantinato Menegon

PurposeConsidering the centrality of the editor-in-chief in the scientific editorial process, this research aimed to investigate what are (if any) the gaps in the current competencies and the future competencies of this professional, according to the evolution of the journals business model.Design/methodology/approachThe qualitative research method was used, seeking a deeper understanding of the studied group and their professional skills in a practical way. The epistemological approach of pragmatism was adopted, and the semi-structured interview technique was used with a sample of 29 interviews.FindingsThe survey results revealed that the editor-in-chief learns his métier on a daily basis, on-the-job, as a result of a lack of prior preparation, due to the absence of structured training of these professionals. The study showed a change in the competencies of the editor-in-chief, but influenced beyond the scientific business model, involving a broader contemporary scenario of high complexity. Finally, it also contributes by highlighting important skills trends for the editor-in-chief.Practical implications It is expected that the results of this research will contribute to institutionalize training and skills development programs for the editor-in-chief and, consequently, for professionalization for the editor-in-chief.Originality/valueThis study deals, for the first time, specifically with the editor-in-chief's skills, where other studies focus on role, functions and responsibilities.


Author(s):  
Martín Gabriel Labarca ◽  
Juan Camilo Martínez González

In April 2015, an international team of researchers announced the measurement, for the first time, of the first ionization energy of lawrencium, a superheavy element of atomic number 103. The experimental result, published in the prestigious scientific journal Nature, led to the reopening of a long-standing debate that concerns the elements that should be part of group 3 of the periodic table. The aim of this paper is to introduce a new line of argumentation to elucidate this problem.


Author(s):  
J. Chakraborty ◽  
A. P. Sinha Hikim ◽  
J. S. Jhunjhunwala

Although the presence of annulate lamellae was noted in many cell types, including the rat spermatogenic cells, this structure was never reported in the Sertoli cells of any rodent species. The present report is based on a part of our project on the effect of torsion of the spermatic cord to the contralateral testis. This paper describes for the first time, the fine structural details of the annulate lamellae in the Sertoli cells of damaged testis from guinea pigs.One side of the spermatic cord of each of six Hartly strain adult guinea pigs was surgically twisted (540°) under pentobarbital anesthesia (1). Four months after induction of torsion, animals were sacrificed, testes were excised and processed for the light and electron microscopic investigations. In the damaged testis, the majority of seminiferous tubule contained a layer of Sertoli cells with occasional spermatogonia (Fig. 1). Nuclei of these Sertoli cells were highly pleomorphic and contained small chromatinic clumps adjacent to the inner aspect of the nuclear envelope (Fig. 2).


Author(s):  
M. Rühle ◽  
J. Mayer ◽  
J.C.H. Spence ◽  
J. Bihr ◽  
W. Probst ◽  
...  

A new Zeiss TEM with an imaging Omega filter is a fully digitized, side-entry, 120 kV TEM/STEM instrument for materials science. The machine possesses an Omega magnetic imaging energy filter (see Fig. 1) placed between the third and fourth projector lens. Lanio designed the filter and a prototype was built at the Fritz-Haber-Institut in Berlin, Germany. The imaging magnetic filter allows energy-filtered images or diffraction patterns to be recorded without scanning using efficient area detection. The energy dispersion at the exit slit (Fig. 1) results in ∼ 1.5 μm/eV which allows imaging with energy windows of ≤ 10 eV. The smallest probe size of the microscope is 1.6 nm and the Koehler illumination system is used for the first time in a TEM. Serial recording of EELS spectra with a resolution < 1 eV is possible. The digital control allows X,Y,Z coordinates and tilt settings to be stored and later recalled.


Author(s):  
Z.L. Wang ◽  
J. Bentley ◽  
R.E. Clausing ◽  
L. Heatherly ◽  
L.L. Horton

Microstructural studies by transmission electron microscopy (TEM) of diamond films grown by chemical vapor deposition (CVD) usually involve tedious specimen preparation. This process has been avoided with a technique that is described in this paper. For the first time, thick as-grown diamond films have been examined directly in a conventional TEM without thinning. With this technique, the important microstructures near the growth surface have been characterized. An as-grown diamond film was fractured on a plane containing the growth direction. It took about 5 min to prepare a sample. For TEM examination, the film was tilted about 30-45° (see Fig. 1). Microstructures of the diamond grains on the top edge of the growth face can be characterized directly by transmitted electron bright-field (BF) and dark-field (DF) images and diffraction patterns.


Author(s):  
Shou-kong Fan

Transmission and analytical electron microscopic studies of scale microstructures and microscopic marker experiments have been carried out in order to determine the transport mechanism in the oxidation of Ni-Al alloy. According to the classical theory, the oxidation of nickel takes place by transport of Ni cations across the scale forming new oxide at the scale/gas interface. Any markers deposited on the Ni surface are expected to remain at the scale/metal interface after oxidation. This investigation using TEM transverse section techniques and deposited microscopic markers shows a different result,which indicates that a considerable amount of oxygen was transported inward. This is the first time that such fine-scale markers have been coupled with high resolution characterization instruments such as TEM/STEM to provide detailed information about evolution of oxide scale microstructure.


Author(s):  
Yimei Zhu ◽  
J. Tafto

The electron holes confined to the CuO2-plane are the charge carriers in high-temperature superconductors, and thus, the distribution of charge plays a key role in determining their superconducting properties. While it has been known for a long time that in principle, electron diffraction at low angles is very sensitive to charge transfer, we, for the first time, show that under a proper TEM imaging condition, it is possible to directly image charge in crystals with a large unit cell. We apply this new way of studying charge distribution to the technologically important Bi2Sr2Ca1Cu2O8+δ superconductors.Charged particles interact with the electrostatic potential, and thus, for small scattering angles, the incident particle sees a nuclei that is screened by the electron cloud. Hence, the scattering amplitude mainly is determined by the net charge of the ion. Comparing with the high Z neutral Bi atom, we note that the scattering amplitude of the hole or an electron is larger at small scattering angles. This is in stark contrast to the displacements which contribute negligibly to the electron diffraction pattern at small angles because of the short g-vectors.


Author(s):  
S.J. Krause ◽  
W.W. Adams

Over the past decade low voltage scanning electron microscopy (LVSEM) of polymers has evolved from an interesting curiosity to a powerful analytical technique. This development has been driven by improved instrumentation and in particular, reliable field emission gun (FEG) SEMs. The usefulness of LVSEM has also grown because of an improved theoretical and experimental understanding of sample-beam interactions and by advances in sample preparation and operating techniques. This paper will review progress in polymer LVSEM and present recent results and developments in the field.In the early 1980s a new generation of SEMs produced beam currents that were sufficient to allow imaging at low voltages from 5keV to 0.5 keV. Thus, for the first time, it became possible to routinely image uncoated polymers at voltages below their negative charging threshold, the "second crossover", E2 (Fig. 1). LVSEM also improved contrast and reduced beam damage in sputter metal coated polymers. Unfortunately, resolution was limited to a few tenths of a micron due to the low brightness and chromatic aberration of thermal electron emission sources.


2020 ◽  
Vol 5 (2) ◽  
pp. 463-478
Author(s):  
Elizabeth Crais ◽  
Melody Harrison Savage

Purpose The shortage of doctor of philosophy (PhD)–level applicants to fill academic and research positions in communication sciences and disorders (CSD) programs calls for a detailed examination of current CSD PhD educational practices and the generation of creative solutions. The intended purposes of the article are to encourage CSD faculty to examine their own PhD program practices and consider the perspectives of recent CSD PhD graduates in determining the need for possible modifications. Method The article describes the results of a survey of 240 CSD PhD graduates and their perceptions of the challenges and facilitators to completing a PhD degree; the quality of their preparation in research, teaching, and job readiness; and ways to improve PhD education. Results Two primary themes emerged from the data highlighting the need for “matchmaking.” The first time point of needed matchmaking is prior to entry among students, mentors, and expectations as well as between aspects of the program that can lead to students' success and graduation. The second important matchmaking need is between the actual PhD preparation and the realities of the graduates' career expectations, and those placed on graduates by their employers. Conclusions Within both themes, graduate's perspectives and suggestions to help guide future doctoral preparation are highlighted. The graduates' recommendations could be used by CSD PhD program faculty to enhance the quality of their program and the likelihood of student success and completion. Supplemental Material https://doi.org/10.23641/asha.11991480


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