scholarly journals Comment on: On the irreducibility of the Severi variety of nodal curves in a smooth surface, by E. Ballico

2019 ◽  
Vol 114 (2) ◽  
pp. 171-174
Author(s):  
Thomas Dedieu
Keyword(s):  
Smooth Surface ◽  
Nodal Curves ◽  
Severi Variety

scholarly journals ON THE POSITION OF NODES OF PLANE CURVES

2020 ◽  
pp. 1-7
Author(s):  
CÉSAR LOZANO HUERTA ◽  
TIM RYAN
Keyword(s):  
Hilbert Scheme ◽  
Plane Curves ◽  
Nodal Curves ◽  
Canonical Class ◽  
Severi Variety

The Severi variety $V_{d,n}$ of plane curves of a given degree $d$ and exactly $n$ nodes admits a map to the Hilbert scheme $\mathbb{P}^{2[n]}$ of zero-dimensional subschemes of $\mathbb{P}^{2}$ of degree $n$ . This map assigns to every curve $C\in V_{d,n}$ its nodes. For some $n$ , we consider the image under this map of many known divisors of the Severi variety and its partial compactification. We compute the divisor classes of such images in $\text{Pic}(\mathbb{P}^{2[n]})$ and provide enumerative numbers of nodal curves. We also answer directly a question of Diaz–Harris [‘Geometry of the Severi variety’, Trans. Amer. Math. Soc.309 (1988), 1–34] about whether the canonical class of the Severi variety is effective.

scholarly journals Severi varieties and Brill–Noether theory of curves on abelian surfaces

2019 ◽  
Vol 2019 (749) ◽  
pp. 161-200 ◽  
Author(s):  
Andreas Leopold Knutsen ◽  
Margherita Lelli-Chiesa ◽  
Giovanni Mongardi
Keyword(s):  
Hyperplane Section ◽  
Abelian Surface ◽  
Moduli Space Of Curves ◽  
Arithmetic Genus ◽  
Abelian Surfaces ◽  
Nodal Curves ◽  
Smooth Curves ◽  
Severi Varieties ◽  
Severi Variety ◽  
Nodal Model

Abstract Severi varieties and Brill–Noether theory of curves on K3 surfaces are well understood. Yet, quite little is known for curves on abelian surfaces. Given a general abelian surface S with polarization L of type {(1,n)} , we prove nonemptiness and regularity of the Severi variety parametrizing δ-nodal curves in the linear system {|L|} for {0\leq\delta\leq n-1=p-2} (here p is the arithmetic genus of any curve in {|L|} ). We also show that a general genus g curve having as nodal model a hyperplane section of some {(1,n)} -polarized abelian surface admits only finitely many such models up to translation; moreover, any such model lies on finitely many {(1,n)} -polarized abelian surfaces. Under certain assumptions, a conjecture of Dedieu and Sernesi is proved concerning the possibility of deforming a genus g curve in S equigenerically to a nodal curve. The rest of the paper deals with the Brill–Noether theory of curves in {|L|} . It turns out that a general curve in {|L|} is Brill–Noether general. However, as soon as the Brill–Noether number is negative and some other inequalities are satisfied, the locus {|L|^{r}_{d}} of smooth curves in {|L|} possessing a {g^{r}_{d}} is nonempty and has a component of the expected dimension. As an application, we obtain the existence of a component of the Brill–Noether locus {{\mathcal{M}}^{r}_{p,d}} having the expected codimension in the moduli space of curves {{\mathcal{M}}_{p}} . For {r=1} , the results are generalized to nodal curves.

Three-Dimensional Structure of Rotavirus-Fab Complex

1990 ◽  
Vol 48 (1) ◽  
pp. 238-239
Author(s):  
B.V.V. Prasad ◽  
E. Marietta ◽  
J.W. Burns ◽  
M.K. Estes ◽  
W. Chiu
Keyword(s):  
Image Processing ◽  
Smooth Surface ◽  
Three Dimensional ◽  
Outer Shell ◽  
Dimensional Structure ◽  
Structural Studies ◽  
Cell Penetration ◽  
Electron Cryomicroscopy ◽  
Image Processing Techniques ◽  
Processing Techniques

Rotaviruses are spherical, double-shelled particles. They have been identified as a major cause of infantile gastroenteritis worldwide. In our earlier studies we determined the three-dimensional structures of double-and single-shelled simian rotavirus embedded in vitreous ice using electron cryomicroscopy and image processing techniques to a resolution of 40Å. A distinctive feature of the rotavirus structure is the presence of 132 large channels spanning across both the shells at all 5- and 6-coordinated positions of a T=13ℓ icosahedral lattice. The outer shell has 60 spikes emanating from its relatively smooth surface. The inner shell, in contrast, exhibits a bristly surface made of 260 morphological units at all local and strict 3-fold axes (Fig.l).The outer shell of rotavirus is made up of two proteins, VP4 and VP7. VP7, a glycoprotein and a neutralization antigen, is the major component. VP4 has been implicated in several important functions such as cell penetration, hemagglutination, neutralization and virulence. From our earlier studies we had proposed that the spikes correspond to VP4 and the rest of the surface is composed of VP7. Our recent structural studies, using the same techniques, with monoclonal antibodies specific to VP4 have established that surface spikes are made up of VP4.

scholarly journals Corrigendum to: Response to “Clarification About ‘Expert Consensus on the Use of a New Bioengineered, Cell-Friendly, Smooth Surface Breast Implant’”

2020 ◽  
Author(s):  
Marcos Sforza ◽  
Dennis C Hammond ◽  
Giovanni Botti ◽  
Per Hedén ◽  
Manuel Chacón Quirós ◽  
...  
Keyword(s):  
Smooth Surface ◽  
Breast Implant ◽  
Expert Consensus

scholarly journals Textile Electrodes: Influence of Knitting Construction and Pressure on the Contact Impedance

Sensors ◽  
2021 ◽  
Vol 21 (5) ◽  
pp. 1578
Author(s):  
Luisa Euler ◽  
Li Guo ◽  
Nils-Krister Persson
Keyword(s):  
Smooth Surface ◽  
Research Field ◽  
Uneven Surface ◽  
Contact Impedance ◽  
Dry Electrodes ◽  
Textile Electrodes ◽  
Human Forearm ◽  
Wet Condition ◽  
Electrode Contact ◽  
Influencing Parameters

Textile electrodes, also called textrodes, for biosignal monitoring as well as electrostimulation are central for the emerging research field of smart textiles. However, so far, only the general suitability of textrodes for those areas was investigated, while the influencing parameters on the contact impedance related to the electrode construction and external factors remain rather unknown. Therefore, in this work, six different knitted electrodes, applied both wet and dry, were compared regarding the influence of specific knitting construction parameters on the three-electrode contact impedance measured on a human forearm. Additionally, the influence of applying pressure was investigated in a two-electrode setup using a water-based agar dummy. Further, simulation of an equivalent circuit was used for quantitative evaluation. Indications were found that the preferred electrode construction to achieve the lowest contact impedance includes a square shaped electrode, knitted with a high yarn density and, in the case of dry electrodes, an uneven surface topography consisting of loops, while in wet condition a smooth surface is favorable. Wet electrodes are showing a greatly reduced contact impedance and are therefore to be preferred over dry ones; however, opportunities are seen for improving the electrode performance of dry electrodes by applying pressure to the system, thereby avoiding disadvantages of wet electrodes with fluid administration, drying-out of the electrolyte, and discomfort arising from a “wet feeling”.

scholarly journals Fabrication and characterization of hexadecyl acrylate cross-linked phase change microspheres

e-Polymers ◽  
2020 ◽  
Vol 20 (1) ◽  
pp. 69-75
Author(s):  
Haoran Yun ◽  
Xingxiang Zhang
Keyword(s):  
Phase Change ◽  
Smooth Surface ◽  
Bone Conduction ◽  
Cross Linking ◽  
Gravimetric Analysis ◽  
Orthopedic Implant ◽  
Thermal Gravimetric ◽  
Fabrication And Characterization ◽  
Fast Release

AbstractMicrospheres with phase change properties were fabricated by polymerization of hexadecyl acrylate (HA) and different cross-linking agents. The samples were characterized by scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA). The results show that, the samples that added cross-linking agents have a smooth surface and the latent heat of them is different. The experiments show that all of the cross-linked copolymer shells can be made into temperature controlled release microspheres. These materials can be potentially applied in the field of thermal energy storage. β-tricalcium phosphate was encapsulated in microspheres to obtain one with a fast release effect. It will effectively promote bone conduction when these microspheres were implanted into a bone defect. This microsphere can be used for orthopedic implant or coating of instrument in the future.

scholarly journals Air mediates the impact of a compliant hemisphere on a rigid smooth surface

Soft Matter ◽  
2021 ◽  
Author(s):  
Siqi Zheng ◽  
Sam Dillavou ◽  
John M. Kolinski
Keyword(s):  
Elastic Body ◽  
Elastic Properties ◽  
Impact Velocity ◽  
Solid Surface ◽  
High Speed ◽  
Smooth Surface ◽  
High Speed Imaging ◽  
The Impact ◽  
Rigid Smooth

When a soft elastic body impacts upon a smooth solid surface, the intervening air fails to drain, deforming the impactor. High-speed imaging with the VFT reveal rich dynamics and sensitivity to the impactor's elastic properties and the impact velocity.

Effect of Sr Doping on Structure and Emittance of La1-xSrxMnO3 Smart Thermal Control Films

2014 ◽  
Vol 602-603 ◽  
pp. 902-905
Author(s):  
Yong Jun Shen ◽  
Chuan Bin Wang ◽  
Ling Li ◽  
Qiang Shen ◽  
Lian Meng Zhang
Keyword(s):  
Thin Film ◽  
Smooth Surface ◽  
Pulsed Laser ◽  
Double Exchange ◽  
Thermal Control ◽  
Laser Deposition ◽  
Lanthanum Manganite ◽  
Infrared Emissivity ◽  
Control Material ◽  
Double Exchange Interaction

Sr-doped lanthanum manganite (La1-xSrxMnO3) is characteristic of thermochromic, which can act as a smart thermal control material used in the variable-emittance devices. In the present study, La1-xSrxMnO3 thin films were prepared on MgO(100) substrates by pulsed laser deposition, and the effect of Sr-doping (x = 0 ~ 0.4) on the structure and infrared emissivity was investigated. Single-phased La1-xSrxMnO3 films with (100)-orientation were obtained, which showed a dense texture with smooth surface. The ratio of Mn4+/Mn3+ in the films was increased with increasing Sr doping, leading to the enhancement in double-exchange interaction and electrical conductivity. As a result, the phase transition from metal to insulator was observed with the increasing of test temperature. For the La0.8Sr0.2MnO3 thin film, a large value of emittance (De = 0.28) was obtained, indicating good variable-emittance by appropriate Sr doping.

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