Penetration of mammalian skin by the infective larva ofNippostrongylus brasiliensis

The behaviour of the third-stage larvae ofNippostrongylus brasiliensishas been studied on rat, mouse and human skin. Locomotion in thin films of moisture is by two-dimensional, undulatory propulsion on skin, and by three-dimensional, undulatory propulsion on hairs. In drops of water or in thick films of moisture locomotion is less efficient than in thin films. It is suggested that the thin film of moisture around larvae on the skin may become coated with a thin monolayer of lipid which could reduce evaporation from the surface of the nematode and from the film of moisture, thus extending the period before desiccation begins. Studies with the electron microscope have shown that the larvae move horizontally into the stratum corneum and later penetrate the epidermis and dermis by separating the constituent cells of these tissues. In the dermis there is dissolution of collagen around the larvae. It is suggested that this separation of cells and dissolution of collagen need not be brought about by enzyme action, as similar effects can be brought about by changes in pH or ionic composition of the bathing medium.

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Nanometer-Thick [(FPEA)2PbX4; X=I, Br] 2D Halide Perovskite Based Thin Films for Pollutant Detection and Nonconventional Photocatalytic Degradation

Materials Advances ◽

10.1039/d1ma00561h ◽

2021 ◽

Author(s):

Arindam Mondal ◽

Akash Lata ◽

Aarya Prabhakaran ◽

Satyajit Gupta

Keyword(s):

Thin Films ◽

Photocatalytic Degradation ◽

Three Dimensional ◽

Two Dimensional ◽

Reduced Dimensionality ◽

P Application ◽

Halide Perovskites ◽

Halide Perovskite ◽

Pollutant Detection

Application of three-dimensional (3D)-halide perovskites (HaP) in photocatalysis encourages the new exercise with two-dimensional (2D) HaP based thin-films for photocatalytic degradation of dye. The reduced dimensionality to 2D-HaPs, with a...

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Studies on the life-history of Bunostomum phlebotomum (Railliet, 1900), a hookworm parasite of cattle

Parasitology ◽

10.1017/s0031182000013354 ◽

1946 ◽

Vol 37 (3-4) ◽

pp. 192-201 ◽

Cited By ~ 13

Author(s):

J. F. A. Sprent

Keyword(s):

Infective Larva ◽

Stage Larva ◽

Fourth Stage ◽

Larval Stages ◽

The Third ◽

Third Stage ◽

History Of ◽

Time Required ◽

Cutaneous Blood ◽

Fourth Stage Larva

A description is given of the processes of copulation, formation of the egg and spermatozoon, cleavage, embryogeny and hatching in B. phlebotomum. These processes were found to be essentially similar to those in other strongyle nematodes.The anatomy of the first three larval stages is described and the observations of Conradi & Barnette (1908) and Schwartz (1924) were largely confirmed.Penetration of the skin of calves by the infective larva was observed histologically. The larvae were found to have reached the dermis within 30 min. and to have penetrated the cutaneous blood vessels within 60 min. of application to the skin. The larvae were found in the lung where the third ecdysis was in progress 10 days after penetration of the skin. A description is given of the growth of the third-stage larva in the lung, the changes which take place during the third ecdysis, and the anatomy of the fourth-stage larva.The fourth-stage larvae exsheath in the lungs and travel to the intestine. After a period of growth in which sexual differentiation takes place, the fourth ecdysis occurs and the adult parasite emerges. The time required for the attainment of maturity was found to be somewhere between 30 and 56 days after penetration of the skin.This paper was written at the Ministry of Agriculture and Fisheries Veterinary Laboratories, Wey-bridge, and the writer would like to express his gratitude to the Director, Prof. T. Dalling, also to Dr W. R. Wooldridge, chairman of the Council of the Veterinary Educational Trust for their help and encouragement. The writer's thanks are also due to Dr H. A. Baylis, Prof. R. T. Leiper and Dr E. L. Taylor for their advice and help on technical points, and to Mr R. A. O. Shonekan, African laboratory assistant, for his able co-operation.

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Microstructure Evolution of Epitaxial (Ba, Sr) TiO3/ (001) HgO Thin Films

MRS Proceedings ◽

10.1557/proc-361-501 ◽

1994 ◽

Vol 361 ◽

Cited By ~ 2

Author(s):

V.A. Alyoshin ◽

E.V. Sviridov ◽

V.I.M. Hukhortov ◽

I.H. Zakharchenko ◽

V.P. Dudkevich

Keyword(s):

Thin Films ◽

Cross Section ◽

Microstructure Evolution ◽

Three Dimensional ◽

Gas Pressure ◽

Smooth Surfaces ◽

Two Dimensional ◽

Surface Versus ◽

Deposition Conditions

ABSTRACTSurface and cross-section relief evolution of ferroelectric epitaxial (Ba,Sr)TiO3 films rf-sputtered on (001) HgO crystal cle-avage surface versus the oxygen worKing gas pressure P and subst-rate temperature T were studied. Specific features of both three-dimensional and two-dimensional epitaxy mechanisms corresponding to various deposition conditions were revealed. Difference between low and high P-T-value 3D epitaxy was established. The deposition of films with mirror-smooth surfaces and perfect interfaces is shown to be possible.

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Two- and three-dimensional locomotion of the nematode Nippostrongylus brasiliensis

Parasitology ◽

10.1017/s0031182000063368 ◽

1990 ◽

Vol 101 (2) ◽

pp. 301-308 ◽

Cited By ~ 4

Author(s):

D. L. Lee ◽

W. D. Biggs

Keyword(s):

Sodium Alginate ◽

Intestinal Mucosa ◽

Three Dimensional ◽

Viscous Medium ◽

Nippostrongylus Brasiliensis ◽

Two Dimensional ◽

Immune Rejection ◽

Forward Movement ◽

Helical Wave ◽

Dimensional Wave

Locomotion of adult Nippostrongylus brasiliensis has been studied in saline, in 0.6% agar, in sodium alginate of different viscosities and amongst sand grains in these media. In saline the nematode formed two-dimensional waves but there was little forward progression. Amongst sand grains in saline the nematode moved forwards by thrusting against sand grains, but thigmokinetic behaviour later resulted in quiescence. In 0.6% agar and in alginates of weak viscosity the nematode produced two-dimensional waves and sometimes a three-dimensional helical wave which resulted in forward movement. The formation of three-dimensional waves and the distance travelled increased with increasing viscosity up to 4% sodium alginate and also amongst sand gains in these media. In 8% sodium alginate the nematode became coiled like a spring but remained almost stationary. The three-dimensional wave is formed with torsion and obtains thrust from the viscous medium. In the intestine of the host thrust will be obtained from the mucus and villi of the intestinal mucosa. The ability of this nematode to move by two-and three-dimensional undulatory propulsion is probably related to its complex ridged cuticle. Attention is drawn to the role that increased viscosity of mucus may play in entrapping nematodes during their immune rejection.

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Tip-Based Nanomachining on Thin Films: A Mini Review

Nanomanufacturing and Metrology ◽

10.1007/s41871-021-00115-5 ◽

2021 ◽

Author(s):

Shunyu Chang ◽

Yanquan Geng ◽

Yongda Yan

Keyword(s):

Thin Film ◽

Thin Films ◽

Data Storage ◽

Three Dimensional ◽

Maintenance Cost ◽

Two Dimensional ◽

Force Microscopy ◽

Atomic Force ◽

Current State ◽

Two Dimensional Materials

AbstractAs one of the most widely used nanofabrication methods, the atomic force microscopy (AFM) tip-based nanomachining technique offers important advantages, including nanoscale manipulation accuracy, low maintenance cost, and flexible experimental operation. This technique has been applied to one-, two-, and even three-dimensional nanomachining patterns on thin films made of polymers, metals, and two-dimensional materials. These structures are widely used in the fields of nanooptics, nanoelectronics, data storage, super lubrication, and so forth. Moreover, they are believed to have a wide application in other fields, and their possible industrialization may be realized in the future. In this work, the current state of the research into the use of the AFM tip-based nanomachining method in thin-film machining is presented. First, the state of the structures machined on thin films is reviewed according to the type of thin-film materials (i.e., polymers, metals, and two-dimensional materials). Second, the related applications of tip-based nanomachining to film machining are presented. Finally, the current situation of this area and its potential development direction are discussed. This review is expected to enrich the understanding of the research status of the use of the tip-based nanomachining method in thin-film machining and ultimately broaden its application.

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Intercalation of pentane into the stage 2 to 4 cesium graphitides: Relation between cesium density in the intercalated layers and the stage of the parent binary

Journal of Materials Research ◽

10.1557/jmr.1993.2288 ◽

1993 ◽

Vol 8 (9) ◽

pp. 2288-2298 ◽

Cited By ~ 2

Author(s):

H. Pillière ◽

M. Goldmann ◽

F. Béguin

Keyword(s):

Room Temperature ◽

Three Dimensional ◽

Structural Transformations ◽

Layer Model ◽

Simultaneous Formation ◽

Ternary Compounds ◽

Second Stage ◽

The Third ◽

Cesium Ions ◽

Third Stage

Isotherms (at 300 K and 328 K) and isobars (in the range 300 to 400 K) of n-pentane intercalation in CsC24 and CsC36 were established. With CsC24, three plateaus were identified at 0.52, 0.7, and 1.0 n-pentane/24 C, whereas only two plateaus at 0.8 and 0.97 n-pentane/36 C were found with CsC36. The progress of the reaction between n-pentane and CsC24, CsC36, and CsC56 (stage 2 to 4) was monitored by real-time neutron diffraction. The intercalation of n-pentane in CsC24 results in the simultaneous formation of a second stage ternary and a first stage binary “CsC8”, whereas, from the third stage CsC36 or the fourth stage CsC56, only pure second stage or third stage ternary compounds are formed, respectively. Owing to the formation of binary domains rich in alkali metal (CsC8) or to stage lowering produced by the ternarization, the in-plane cesium density is smaller in the ternary layer than in the starting binary. The electrostatic repulsion between the cesium ions, provoked by the sorption of n-pentane, is believed to be at the origin of the increased coverage. During the intercalation or de-intercalation processes, three-dimensional segregation occurs in each grain. A pleated layer model with canted fronts is presented. It accounts for the various phases present within each grain and for the structural transformations caused by pressure variations. At room temperature, the ternary layer seems to be disordered. The order-disorder transition appearing either by decreasing the temperature or by increasing the n-pentane pressure is correlated to a hindered motion of the intercalated molecules.

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New insights into the suitability of the third dimension for visualizing multivariate/multidimensional data: A study based on loss of quality quantification

Information Visualization ◽

10.1177/1473871614556393 ◽

2014 ◽

Vol 15 (1) ◽

pp. 3-30 ◽

Cited By ~ 14

Author(s):

Antonio Gracia ◽

Santiago González ◽

Víctor Robles ◽

Ernestina Menasalvas ◽

Tatiana von Landesberger

Keyword(s):

Analytical Approach ◽

Distance Perception ◽

Statistical Tests ◽

Three Dimensional ◽

Multidimensional Data ◽

Two Dimensional ◽

Dimensional Representation ◽

The Third ◽

Quality Degradation ◽

Third Dimension

Most visualization techniques have traditionally used two-dimensional, instead of three-dimensional representations to visualize multidimensional and multivariate data. In this article, a way to demonstrate the underlying superiority of three-dimensional, with respect to two-dimensional, representation is proposed. Specifically, it is based on the inevitable quality degradation produced when reducing the data dimensionality. The problem is tackled from two different approaches: a visual and an analytical approach. First, a set of statistical tests (point classification, distance perception, and outlier identification) using the two-dimensional and three-dimensional visualization are carried out on a group of 40 users. The results indicate that there is an improvement in the accuracy introduced by the inclusion of a third dimension; however, these results do not allow to obtain definitive conclusions on the superiority of three-dimensional representation. Therefore, in order to draw further conclusions, a deeper study based on an analytical approach is proposed. The aim is to quantify the real loss of quality produced when the data are visualized in two-dimensional and three-dimensional spaces, in relation to the original data dimensionality, to analyze the difference between them. To achieve this, a recently proposed methodology is used. The results obtained by the analytical approach reported that the loss of quality reaches significantly high values only when switching from three-dimensional to two-dimensional representation. The considerable quality degradation suffered in the two-dimensional visualization strongly suggests the suitability of the third dimension to visualize data.

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