scholarly journals Shampoo, conditioner and hair washing

Author(s):  
Neethu Mary George ◽  
Amruthavalli Potlapati

<p>Modern shampoos are much more than just cleansing agents. With rising demands for new milder and ‘greener’ products, the developments in the field of shampoo and conditioners are moving at a faster pace than ever before. Soaps were initially used to clean scalp but are not recommended for hair cleansing because they leave behind a soap scum when mixed with hard water that is difficult to rinse from the hair and scalp. There are different types of shampoos. Besides “normal” cleaning shampoo, there are “specific” shampoos that have additional ingredients targeting some hair problems. Dermatologists most frequently prescribe shampoos but little is taught in medical schools about the hair cosmetics. Most of the prescriptions are based only on the treatment of the scalp and usually disregards the hair fibre health. Hence it is imperative for dermatologists to known about the mechanism of shampoos, different surfactants and where to choose which shampoo.</p>

2018 ◽  
Vol 42 (4) ◽  
pp. 693-696 ◽  
Author(s):  
Luiz Fernando Quintanilha ◽  
Gustavo Nunes Costa ◽  
Marcio Ramos Coutinho

In the field of medical education, it is possible to consider that the acquisition of professional competences can gain new contours when considering the use of active methodologies. It is important to analyze the perception of the students about the use of them in medical courses, as well as to reflect on their challenges and potentials. In the present study, a semistructured questionnaire of student perception was applied immediately after the execution of different types of active methodologies in the discipline of physiology in two medical courses. The results suggest a highly positive evaluation of the use of active methodologies by the student body of the two institutions. The students evaluated positively the application of the method (94.6%) and the perception about the learning (84.1%). On the other hand, when questioned about the substitution of the traditional expository method by the active methodologies, there was a tendency to the centrality of the answers, with 84.0% of the responses concentrated at positions 2, 3, and 4 on a scale of 1 (minimum) to 5 (maximum) on the Likert scale. There were no statistically significant differences when comparing variables of age, sex, and previous graduation. Although there was no consensus regarding the full replacement of traditional for active methodologies, one can conclude that the students’ perception about the introduction of said methodologies in the teaching of physiology in medical courses is positive, regardless of the subgroups evaluated. These results encourage the insertion of these and other methodologies into medical courses.


1986 ◽  
Vol 23 (04) ◽  
pp. 851-858 ◽  
Author(s):  
P. J. Brockwell

The Laplace transform of the extinction time is determined for a general birth and death process with arbitrary catastrophe rate and catastrophe size distribution. It is assumed only that the birth rates satisfyλ0= 0,λj&gt; 0 for eachj&gt; 0, and. Necessary and sufficient conditions for certain extinction of the population are derived. The results are applied to the linear birth and death process (λj=jλ, µj=jμ) with catastrophes of several different types.


2020 ◽  
Vol 43 ◽  
Author(s):  
Rajen A. Anderson ◽  
Benjamin C. Ruisch ◽  
David A. Pizarro

Abstract We argue that Tomasello's account overlooks important psychological distinctions between how humans judge different types of moral obligations, such as prescriptive obligations (i.e., what one should do) and proscriptive obligations (i.e., what one should not do). Specifically, evaluating these different types of obligations rests on different psychological inputs and has distinct downstream consequences for judgments of moral character.


Author(s):  
P.L. Moore

Previous freeze fracture results on the intact giant, amoeba Chaos carolinensis indicated the presence of a fibrillar arrangement of filaments within the cytoplasm. A complete interpretation of the three dimensional ultrastructure of these structures, and their possible role in amoeboid movement was not possible, since comparable results could not be obtained with conventional fixation of intact amoebae. Progress in interpreting the freeze fracture images of amoebae required a more thorough understanding of the different types of filaments present in amoebae, and of the ways in which they could be organized while remaining functional.The recent development of a calcium sensitive, demembranated, amoeboid model of Chaos carolinensis has made it possible to achieve a better understanding of such functional arrangements of amoeboid filaments. In these models the motility of demembranated cytoplasm can be controlled in vitro, and the chemical conditions necessary for contractility, and cytoplasmic streaming can be investigated. It is clear from these studies that “fibrils” exist in amoeboid models, and that they are capable of contracting along their length under conditions similar to those which cause contraction in vertebrate muscles.


Author(s):  
U. Aebi ◽  
P. Rew ◽  
T.-T. Sun

Various types of intermediate-sized (10-nm) filaments have been found and described in many different cell types during the past few years. Despite the differences in the chemical composition among the different types of filaments, they all yield common structural features: they are usually up to several microns long and have a diameter of 7 to 10 nm; there is evidence that they are made of several 2 to 3.5 nm wide protofilaments which are helically wound around each other; the secondary structure of the polypeptides constituting the filaments is rich in ∞-helix. However a detailed description of their structural organization is lacking to date.


Author(s):  
E. L. Thomas ◽  
S. L. Sass

In polyethylene single crystals pairs of black and white lines spaced 700-3,000Å apart, parallel to the [100] and [010] directions, have been identified as microsector boundaries. A microsector is formed when the plane of chain folding changes over a small distance within a polymer crystal. In order for the different types of folds to accommodate at the boundary between the 2 fold domains, a staggering along the chain direction and a rotation of the chains in the plane of the boundary occurs. The black-white contrast from a microsector boundary can be explained in terms of these chain rotations. We demonstrate that microsectors can terminate within the crystal and interpret the observed terminal strain contrast in terms of a screw dislocation dipole model.


Author(s):  
E.M. Kuhn ◽  
K.D. Marenus ◽  
M. Beer

Fibers composed of different types of collagen cannot be differentiated by conventional electron microscopic stains. We are developing staining procedures aimed at identifying collagen fibers of different types.Pt(Gly-L-Met)Cl binds specifically to sulfur-containing amino acids. Different collagens have methionine (met) residues at somewhat different positions. A good correspondence has been reported between known met positions and Pt(GLM) bands in rat Type I SLS (collagen aggregates in which molecules lie adjacent to each other in exact register). We have confirmed this relationship in Type III collagen SLS (Fig. 1).


Author(s):  
K. A. Brookes ◽  
D. Finbow ◽  
Madeleine Samuel

Investigation of the particulate matter contained in the water sample, revealed the presence of a number of different types and certain of these were selected for analysis.An A.E.I. Corinth electron microscope was modified to accept a Kevex Si (Li) detector. To allow for existing instruments to be readily modified, this was kept to a minimum. An additional port is machined in the specimen region to accept the detector, with the liquid nitrogen cooling dewar conveniently housed in the left hand cupboard adjacent to the microscope column. Since background radiation leads to loss in the sensitivity of the instrument, great care has been taken to reduce this effect by screening and manufacturing components that are near the specimen from material of low atomic number. To change from normal transmission imaging to X-ray analysis, the special 4-position specimen rod is inserted through the normal specimen airlock.


Author(s):  
Kazumichi Ogura ◽  
Michael M. Kersker

Backscattered electron (BE) images of GaAs/AlGaAs super lattice structures were observed with an ultra high resolution (UHR) SEM JSM-890 with an ultra high sensitivity BE detector. Three different types of super lattice structures of GaAs/AlGaAs were examined. Each GaAs/AlGaAs wafer was cleaved by a razor after it was heated for approximately 1 minute and its crosssectional plane was observed.First, a multi-layer structure of GaAs (100nm)/AlGaAs (lOOnm) where A1 content was successively changed from 0.4 to 0.03 was observed. Figures 1 (a) and (b) are BE images taken at an accelerating voltage of 15kV with an electron beam current of 20pA. Figure 1 (c) is a sketch of this multi-layer structure corresponding to the BE images. The various layers are clearly observed. The differences in A1 content between A1 0.35 Ga 0.65 As, A1 0.4 Ga 0.6 As, and A1 0.31 Ga 0.69 As were clearly observed in the contrast of the BE image.


Author(s):  
Thao A. Nguyen

It is well known that the large deviations from stoichiometry in iron sulfide compounds, Fe1-xS (0≤x≤0.125), are accommodated by iron vacancies which order and form superstructures at low temperatures. Although the ordering of the iron vacancies has been well established, the modes of vacancy ordering, hence superstructures, as a function of composition and temperature are still the subject of much controversy. This investigation gives direct evidence from many-beam lattice images of Fe1-xS that the 4C superstructure transforms into the 3C superstructure (Fig. 1) rather than the MC phase as previously suggested. Also observed are an intrinsic stacking fault in the sulfur sublattice and two different types of vacancy-ordering antiphase boundaries. Evidence from selective area optical diffractograms suggests that these planar defects complicate the diffraction pattern greatly.


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