Tapering Shape Research Articles

The Ninth and Tenth Costal Cartilages are Available and Safe Options for Rhinoplasty: A Cadaveric Anatomical Study.

Some authors prefer the ninth costal cartilage for autogenous rhinoplasty, but few anatomical studies focus on tapering shape and harvesting safety regarding pneumothorax risk. Therefore, we studied the size and related anatomy of the ninth and tenth costal cartilages.Twelve fresh cadavers (24 ribs) were studied. We measured the length, width, and thickness of the ninth and tenth costal cartilages at the osteochondral junction (OCJ), midpoint and tip. To evaluate safety during harvesting, we measured the thickness of the transversus abdominis muscle beneath the costal cartilage.The mean lengths of the ninth and tenth cartilages were 99.1±25.0 and 60.6±22.5 mm, respectively. The ninth cartilage was 11.8±2.6, 9.0±2.4, and 2.5±0.5 mm wide, and the tenth cartilage was 9.9±2.0, 7.1±2.0, and 2.7±0.5 mm wide at the OCJ, midpoint and tip, respectively. The ninth cartilage was 8.4±2.0, 6.4±1.5, and 2.4±0.6 mm thick, and the tenth cartilage was 7.0±2.2, 5.1±1.7, and 2.3±0.5 mm thick at each point. For the transversus abdominis muscle, the thickness was 2.1±0.9, 3.7±1.0, and 4.5±1.3 mm at the ninth cartilage and 1.9±0.5, 2.9±1.1, and 3.7±1.4 mm at the tenth cartilage at each point.The size of the cartilage was sufficient for autogenous rhinoplasty. The transversus abdominis muscle provides thickness for safe harvesting. Furthermore, if this muscle is breached during cartilage harvest, the abdominal cavity is exposed but not the pleural cavity. Consequently, there is a very low risk of pneumothorax at this level.

Identification of seven types of pili in Mycobacterium tuberculosis: Using atomic force microscopy.

Pili are polymeric, hydrophobic, proteinaceous structures generally composed of a major repeating subunit called pilin and, in some cases, a minor tip-associated adhesin subunit. Pili are involved in many virulence-associated functions, such as biofilm formation, adherence, and colonization of mucosal surfaces. Mycobacterium tuberculosis (MTB) strains were isolated from clinically and laboratory-confirmed cases of tuberculosis (TB). The TB isolates were subjected to the Xpert MTB/rifampicin test and then, further susceptibility testing was performed on them against first- and second-line drugs using proportional methods. Thereafter, the selected isolates were subculture in Dubos Tween-albumin liquid culture medium, and at their exponential growth phase (OD600 = 0.05 (5 × 106 colony-forming unit/mL), cells were observed under atomic force microscopy (AFM). For each isolate, 15-20 steel sample packs were prepared and observed under AFM. Here, the data presented are the result of average observation. Under AFM, seven different types of pili were detected, out of which four types, i.e., Type III, Type IV secretion pili, and Type IV-like pili, curli-like pili (MTP) were similar to reported pili in Gram-negative and Gram-positive bacteria. Whereas the other three forms, i.e., Type V (relief funnel pili), Type VI (adhesion tapering), and Type VII (adhesion flap pili), were newly identified and named according to their appearance. Both Types of IV pili were detected in all clinical isolates irrespective of their susceptibility patterns, although significant differences were observed from the side of their protruding. Type Curli pili is similar in appearance in all clinical isolates. Types VI and VII were detected only in extensively drug-resistant and totally drug-resistant-TB isolates (100%). The Type III pili (secretion needle pili) was present in both susceptible- and drug-resistant bacilli, although in drug-resistant strains, we found a considerable difference in their length (50 μ ±10 nm in length) and sometimes, they also had tapering at end. The Type V pili was seen in susceptible isolates but it was at the resting stage (100%; lying aside of cell wall) whereas in drug-resistant isolates, they were getting apart from the cell wall of bacilli with a clear tapering or funnel shape structure. The results of this study highlight the importance of new types of pili expressions in respect of susceptibility patterns in TB. The identified new types of pili would be promising approaches for the treatment and prevention of drug-resistant TB, which needs further investigation.

A new species of crown-of-thorns sea star, Acanthaster benziei sp. nov. (Valvatida: Acanthasteridae), from the Red Sea

A new species of crown-of-thorns sea star (CoTS), Acanthaster benziei sp. nov., is described based on four specimens collected from Saudi Arabia's Red Sea coast where it inhabits coral reefs. Species delimitation from congeners in the species complex, i.e., Acanthaster planci, Acanthaster mauritiensis and Acanthaster cf. solaris, is primarily based on distinct and diagnostic mitochondrial DNA sequence regions. Species separation of Acanthaster benziei is additionally justified due to diagnostic morphological characters: fewer arms; narrower and thinner spines; fanned spine tips in primary and latero-oral spines; a wider tip or tapering shape in circumoral spines; and rhombus-shaped oral pedicellariae.

Field enhancement of optical bowtie nano‐antenna using exponential tapered profile

In this work, both the near-field and far-field optical properties of curved sides bowtie nano-antenna are investigated in the near-infrared range. The curvature of the proposed structure is based on the Vivaldi antenna tapering shape. The effect of tapering rate on the near-field enhancement is studied, and the results show that the proposed antenna structure produces better field enhancement compared with conventional bowtie antenna with linear sides and hence it is promising for energy harvesting and microscopy applications. Also, the far-field properties are studied to decide the validity of the structure in optical communication applications.

Parametric design of diagrid tall buildings regarding structural efficiency

ABSTRACTIn this paper, the effects of form parameters on the structural efficiency of tall buildings are investigated by generating a parametric platform. The modifications of the form are normally adopted by architects in tall buildings to satisfy their aesthetic and functional needs. The effects of tapering and changing plan shape as two commonly used modifications, are investigated applying the diagrid structural system which provides the structure with high stiffness and efficiency as well as satisfying the architectural needs. Forms are generated in Rhinoceros and exported to SAP2000 to be analysed structurally through a response spectrum analysis. The results show tapering in the height section leads to more impacts on structural efficiency parameters in comparison to plan changes. The circle and the polygons with more sides create more efficient forms. Some outcomes show more than 20% lighter structures in concave sections than normal buildings.

Effect of Lateral End Plates on Flow Crossing a Yawed Circular Cylinder

Numerical simulation is carried out to investigate the effect of the boundary condition of two lateral end-plate walls on the flow structure in the wake of a flow crossing a yawed circular cylinder. Two typical boundary conditions, nonslip and periodic, are investigated. It is revealed that the boundary condition of the two end-plates has a significant effect on the flow behaviors in the wake. Under the nonslip boundary condition, the vortex structure in the wake exhibits a tapering shape to the tip end. The flow pattern is formed in the wake as the streamlines on the tip side are becoming denser while the streamlines on the base end are becoming sparser. Spectral power analysis of the local lift coefficient shows that the frequency distribution exhibits axial variation. On the base side, the frequency distribution is broadband. On the tip side, there are two peak frequencies: the larger one corresponds to the value predicted by the independence principle, and the smaller one is generated by the secondary axial flow separation from the rear cylinder wall. Under the periodic condition, the numerical results show that organized Strouhal vortex is shed in the wake in the same way as to the flow orthogonally passing a cylinder and the independence principle is still applicable.

Supertall in Seoul

The first supertall building in South Korea, the 555 m Lotte World Tower, in Seoul, features a gently curving, tapered shape and a mast, dubbed the “lantern,” that consists of two separate diagrid structures that extend 50 m above the top occupied floor. Although the tapering shape presented significant challenges during design and construction of the 123-story structure, it effectively minimizes the wind loads on the tower.

Etching effect of tertiary-butyl chloride during InP-nanowire growth

We investigated the etching effect of tertiary-butyl chloride (TBCl) during InP nanowire (NW) growth for the purpose of improving the tapering shape at high growth temperature. The vapor–liquid–solid method was performed by using 10-nm-diameter Au particles for NW growth. The InP NW length doubled when TBCl was supplied at the same flow rate as TMIn and decreased gradually with increasing TBCl flow, while the volume monotonically decreased. The TBCl effectively suppressed growth in the radial direction. We also systematically studied the dependence of NW length and volume on growth time, growth temperature, and TMIn flow rate with and without TBCl. The crystalline structure was apparently varied within our growth condition range. At high growth temperature and low TBCl flow rate, the NWs tended to have a wurtzite-based structure.

Preliminary report on a new concept stent prototype designed for venous implant.

Venous obstruction at iliocaval level in both forms, primary and secondary, is a significant cause of severe chronic venous insufficiency. A new therapeutic approach to this pathology emerged with the introduction of stenting procedures that proved effective, leading to good long-term results. However, at present, the majority of implanted stents have been designed for arterial implant and this can pose a limit in particular districts. The purpose of this preliminary acute study was to verify the deliverability and safety of a new stent specially designed for venous-vessel implant. We assess the safety and deliverability of two braided, self-expanding, nickel-titanium stents (Jotec GmbH, Hechingen, Germany) specially designed for endovascular implant in veins. The two stents, despite being based on the same concept, have a different design: stent A presents a proximal tapering shape specially designed to reduce migration, while stent B does not. Both of them are enlarged at their distal extremity and present variable radial force the length of the stent itself, the said force becoming very high in the intermediate segment. Stents were implanted in the internal jugular vein of a sheep, showing optimal deliverability. The completion venography showed the migration of stent B into the right atrium. Stent A maintained its location, confirmed by intravascular ultrasound examination. No scaffolding effect was detected and an adequate adherence and adaptability to the vein wall was obtained. In conclusions, the stent A design matches the characteristics required by vein implants. Stability is achieved even where difficult anatomical conditions apply, such as in the jugular vein. Deployment is easy and precise in a given landing zone. Radial resistive force is very high, as required in specific vein districts, but is also associated with good flexibility. Following this preliminary acute report, further studies are required.

Au-free InAs nanowires grown in In-particle-assisted vapor-liquid-solid mode: growth, structure, and electrical property

We investigated the growth, structure, and electrical properties of InAs nanowires grown in the Au-free vapor-liquid-solid mode. We demonstrated the self-assisted vapor-liquid-solid growth of InAs nanowire with self-assembled In particles on InP substrates. We found that the III/V source mole ratio has a significant effect on the growth behavior and tapering shape. With a high III/V mole ratio (>0.11), a pure In particle at the tip of a nanowire makes it possible to grow the InAs nanowire in the self-assisted vapor-liquid-solid mode. We also found that the growth temperature range of the self-assisted vapor-liquid-solid growth was quite narrow compared with the conventional Au-assisted vapor-liquid-solid mode. A single InAs nanowire grown with a high III/V mole ratio exhibits distinct TO phonon peak in a Raman spectroscopy observation. We further verified that an undoped InAs nanowire grown in the self-assisted vapor-liquid-solid mode could function as a channel in a field-effect transistor device and the undoped nanowire exhibits n-type conduction behavior.

Sword and Dagger Pommels Associated with the Crusades, Part II: A Technical Study

The article discusses the results of a technical study of a collection of medieval sword and dagger pommels owned by the Metropolitan Museum of Art in New York City, with particular focus given to the probable use of the lost-wax technique to create them and the conclusion that they were most likely created in Europe due to the presence of Champleve enameling. A brief overview of medieval metalwork is presented, and the pommels and their creation are described in detail. The association of the pommels with the crusades is also commented on.

Possible functional consequences of structural adaptation along single arterioles

Arterioles are normally thought of as having a constant structural diameter between branch points. In unbranched rat cremaster arterioles, however, structural diameter increases downstream along the vessel (upstream tapering) without change in cross‐sectional area of the vascular wall (1). We addressed the possible functional consequence of this configuration by flow‐simulations comparing myogenically active vessels of uniform structural radius with those having an upstream tapering shape. In our model cross‐sectional area of the vascular wall remains invariant along the vessel and the flow is the same in all cases.ResultsThe vascular wall material can be arranged in an upstream tapering configuration such that circumferential wall stress is uniform along the vessel. The stress remains uniform during flow‐autoregulation when perfusion pressure is changed. In contrast, when the structural radius is uniform along the vessel wall stress is much higher upstream than downstream, and this difference is maintained under variations in perfusion pressure.ConclusionIn a myogenically active vessel upstream tapering of the inner radius allows the circumferential wall stress, and hence possibly the contractile state of the wall smooth muscle cells, to remain constant along the vessel at a given pressure. This is not the case for a vessel with a uniform radius. The upstream tapering shape is consistent with the vascular wall cells having a uniform point of operation as regards stress‐induced myogenic contraction.

Effect of tapering shape on performance of broadside‐coupled directional couplers

AbstractA theoretical model is used to investigate effect of the tapering shape on performance of the broadside‐coupled directional coupler. It is shown that the tapering shape has a significant effect on the overall performance. Concave shapes give a broader bandwidth compared with the convex shapes. The model also shows that a proper choice of the tapering shape can result in a significant improvement in the performance across a wide bandwidth. The theoretical findings of the model are supported by simulations, and measurements. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 1285–1288, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24325

A new species of electric knifefish, genus Compsaraia (Gymnotiformes: Apteronotidae) from the Amazon River, with extreme sexual dimorphism in snout and jaw length

A new species of the neotropical electric fish genus Compsaraia is described from the western Amazon of Peru and Brazil. Compsaraia samueli is distinguishable from all other apteronotids by sexual dimorphism in which mature males exhibit extreme elongation and slenderness of the snout and jaws. Compsaraia samueli is readily distinguishable from its only congener, C. compsa, by more caudal‐fin rays (17–18 vs. 13–16), a shorter caudal peduncle (mean length 9% vs. 34% body length to end of anal fin), a less tapering body shape in lateral profile (mean ratio of body depth at origins of anal fin and dorsal organ 93% vs. 75%), and a smaller maximum adult body size (230 vs. 305 mm). The genus Compsaraia is readily separated from other apteronotids by a pale antorbital stripe and a pale L‐shaped patch over the supra‐temporal canal. The phylogenetic position of C. samueliis estimated by inclusion in a previously published data matrixof osteological and other morphological characters. Comparisons of the cranial bones in apteronotids shows the derived morphology of C. samueli to be a composite of three developmentally and phylogenetically discrete characters: (1) positive allometric growth before sexual maturity in both sexes of the pre‐orbital region of the neurocranium, (2) positive allometric growth of the (oral) jaws, and (3) secondary sexual dimorphism of snout and jaw morphology. The genus Compsaraia represents one of at least three phylogenetically independent cases of snout elongation and one of at least four cases of jaw elongation within the Apteronotidae. Compsaraia samueli also represents one of at least four cases of secondary sexual dimorphism in snout and jaw length within the Apteronotidae. The phylogenetic distribution of snout and jaw characters within the Apteronotidae suggests the influence of both sexual and trophic functional influences on the evolution of head morphology.

A Tapered Slot Antenna with Flat and High Gain for Ultra-Wideband Applications

An elliptically tapered slot antenna (TSA) with high and relatively-flat gain is proposed in this paper. Its measured 10-dB impedance bandwidth is 2.65–12.90 GHz which covers the frequency range of ultra-wideband (UWB). Meanwhile, on the lower band of UWB (3 to 5 GHz), the measured antenna gain varies within 9.25 to 10.25 dBi. Furthermore, differing from many TSAs, the ground plane is just a simple rectangular structure but not a tapering shape.

A study on electrode wear sensing and compensation in Micro-EDM using machine vision system

This paper presents an electrode wear compensation method based on a machine vision system for micro-electro-discharge machining (EDM). Front wear and corner wear of tool electrode can be measured and evaluated in a direct manner by the vision system’s image-processing software capabilities. Tool electrode images have depicted that the front wear and corner wear were increased rapidly during EDM drilling and EDM milling, respectively, and thus contributing to an arc and a tapering shape at the end of tool electrode, respectively. Both the depth of the hole and depth of the groove are linearly proportional to the length of the front wear. A new electrode wear compensation method is presented based on the direct measurement of the front wear. Experimental results not only verify the usefulness of the electrode wear compensation method in micro-EDM, they also demonstrate that the machining time can be significantly reduced by 40% when using the proposed method, compared to the uniform wear method.

Growth and characterization of GaP nanowires on Si substrate

The integration of III-V semiconductor materials with Si technology is of great interest for optoelectronic integration circuits. We have studied the growth and structural aspects of GaP nanowires (NWs) grown on Si substrate in a metalorganic vapor phase epitaxy system. Au colloid particles dispersed on Si substrate were used as catalysts to conduct the NW growth. The growth temperature considerably affected the growth rate and shape of GaP NWs. The growth rate showed a maximum value of 14.69nm∕s at 480°C. When growth temperature increased the radial growth on NW sides was enhanced and the NWs therefore exhibited a tapering shape. GaP NWs with a uniform diameter could be grown at a growth temperature as low as 420°C using a two-temperature process. The NW diameter could be well controlled by using size-selective Au colloid particles. The growth rate dependence showed that the thin NWs grew more slowly than thick ones and the V∕III source ratio had a significant effect on the growth rate dependence. An analysis of the GaP∕Si interface by transmission electron microscopy indicated that the NWs were epitaxially grown on the Si(111) substrate. Based on these experimental results, the growth mechanism of the GaP NWs on Si was discussed.

Study of a dynamic-shape-curve function for a fused tapering optical fiber

For the fused tapering optical fibers, a physics-mathematics equation of dynamic-shape curves is deduced. The closed-form solution of the equation can be acquired by use of its initial, boundary, and volume-conserved conditions. The shape curves in different tapering processes can be described by the solution conveniently, accurately, and integratively. A large quantity of experimental data has been provided and shown to have a coincidence with the theoretical results properly. Especially, the initial length of the fused zone is known, and the solution can predict the whole tapering shape curve with an arbitrary elongating length.

Influence of Nanowire Density on the Shape and Optical Properties of Ternary InGaAs Nanowires

We have synthesized ternary InGaAs nanowires on (111)B GaAs surfaces by metal-organic chemical vapor deposition. Au colloidal nanoparticles were employed to catalyze nanowire growth. We observed the strong influence of nanowire density on nanowire height, tapering, and base shape specific to the nanowires with high In composition. This dependency was attributed to the large difference of diffusion length on (111)B surfaces between In and Ga reaction species, with In being the more mobile species. Energy dispersive X-ray spectroscopy analysis together with high-resolution electron microscopy study of individual InGaAs nanowires shows large In/Ga compositional variation along the nanowire supporting the present diffusion model. Photoluminescence spectra exhibit a red shift with decreasing nanowire density due to the higher degree of In incorporation in more sparsely distributed InGaAs nanowires.

The functional anatomy of Kager's fat pad in relation to retrocalcaneal problems and other hindfoot disorders

Kager's fat pad is a mass of adipose tissue occupying Kager's triangle. By means of a combined magnetic resonance imaging, ultrasound, gross anatomical and histological study, we show that it has three regions that are closely related to the sides of the triangle. Thus, it has parts related to the Achilles and flexor hallucis longus (FHL) tendons and a wedge of fat adjacent to the calcaneus. The calcaneal wedge moves into the bursa during plantarflexion, as a consequence of both an upward displacement of the calcaneus relative to the wedge and a downward displacement of the wedge relative to the calcaneus. During dorsiflexion, the bursal wedge is retracted. The movements are promoted by the tapering shape of the bursal wedge and by its deep synovial infolds. Fibrous connections linking the fat to the Achilles tendon anchor and stabilize it proximally and thus contribute to the motility of its tip. We conclude that the three regions of Kager's fat pad have specialized functions: an FHL part which contributes to moving the bursal wedge during plantarflexion, an Achilles part which protects blood vessels entering this tendon, and a bursal wedge which we suggest minimizes pressure changes in the bursa. All three regions contribute to reducing the risk of tendon kinking and each may be implicated in heel pain syndromes.