beta sheet

(noun)

A secondary structure in proteins consisting of multiple strands connected laterally.

Related Terms

Examples of beta sheet in the following topics:

  • Secondary & Tertiary Structure of Large Peptides and Proteins

    • By convention, beta-sheets are designated by broad arrows or cartoons, pointing in the direction of the C-terminus.
    • Some proteins have layered stacks of β-sheets, which impart structural integrity and may open to form a cavity (a beta barrel).
    • When beta-sheets are observed as secondary structural components of globular proteins, they are twisted by about 5 to 25º per residue; consequently, the planes of the sheets are not parallel.
    • Although most proteins and large peptides may have alpha-helix and beta-sheet segments, their tertiary structures may consist of less highly organized turns, strands and coils.
    • A large section of antiparallel beta-sheets is colored violet, and a short alpha-helix is green.

  • Modes of Radioactive Decay

    • The types we will discuss here are: alpha, beta, and gamma (listed in increasing ability to penetrate matter).
    • Alpha particles carry a positive charge, beta particles carry a negative charge, and gamma rays are neutral.
    • Alpha particles have greater mass than beta particles.
    • Alpha particles can be completely stopped by a sheet of paper.
    • Beta particles can be stopped by aluminum shielding.

  • B.4 Chapter 4

    • This problem will work best if you have a sheet of graph paper.
    • $\displaystyle p^\mu = \left [ \begin{array}{c} m c \frac{1+\beta^2}{1-\beta^2} \\ m \frac{2v}{1-\beta^2} \\ 0 \\ 0 \end{array} \right ]$
    • $\displaystyle p^\mu = \left [ \begin{array}{c} m c \frac{1+\beta^2}{1-\beta^2} \\ -mc \frac{2\beta}{1-\beta^2} \\ 0 \\ 0 \end{array} \right ]$
    • My pal is travelling toward me in the opposite direction of the photon at a velocity$\beta c$$\gamma = \left ( 1- \beta^2\right)^{-1/2}$.
    • My pal is still coming toward me at a velocity $\beta c$.

  • Beta Decay

    • Beta decay is a type of radioactive decay in which a beta particle (an electron or a positron) is emitted from an atomic nucleus.
    • There are two types of beta decay.
    • Beta minus (β) leads to an electron emission (e−); beta plus (β+) leads to a positron emission (e+).
    • Beta decay is mediated by the weak force.
    • The continuous energy spectra of beta particles occur because Q is shared between a beta particle and a neutrino.

  • Problems

    • This problem will work best if you have a sheet of graph paper.In a spacetime diagram one draws a particular coordinate (in our case $x$) along the horizontal direction and the time coordinate vertically.People also generally draw the path of a light ray at 45$^\circ$.This sets the relative units of the two axes.
    • Write out the Lorentz transformation matrix for a boost in the x−direction to a velocity $\beta _x$.
    • Write out the Lorentz transformation matrix for a boost in the y−direction to a velocity$\beta_y$.
    • Write out the Lorentz transformation matrix for a boost in the x−direction to velocity $\beta_x$ followed by boost to a velocity $\beta_y$ in the y−direction.
    • Write out the Lorentz transformation matrix for a boost in the x−direction to velocity $\beta_x$, followed by boost to a velocity $\beta_y$ in the y−direction, followed a boost in the x−direction to velocity −$\beta_x$ followed by boost to a velocity −$\beta_y$ in the y−direction.

  • The Fields

    • $\displaystyle \beta \equiv \frac{\bf u}{c},~\text{so}~ \kappa = 1 - {\bf n} \cdot \beta$
    • $\displaystyle {\bf E}(r,t) = \kern-2mm q \left [ \frac{({\bf n} - \beta)(1-\beta^2)}{\kappa^3 R^2} \right ]_\mathrm{ret}\!
    • \frac{q}{c} \left [ \frac{\bf n}{\kappa^3 R} \times \left [ ({\bf n} - \beta ) \times \dot{\beta} \right ]\right ]_\mathrm{ret} \\ {\bf B}(r,t) = \kern-2mm\left [ {\bf n} \times {\bf E}(r,t) \right ]_\mathrm{ret}.$
    • $\displaystyle {\bf E}_{rad}(r,t) = + \frac{q}{c} \left [ \frac{\bf n}{\kappa^3 R} \times \left [ ({\bf n} - \beta ) \times \dot{\beta} \right ]\right ] \\ {\bf B}_{rad}(r,t) = \left [ {\bf n} \times {\bf E}_{rad}(r,t) \right ].$
    • $\displaystyle {\bf S} = {\bf n} \frac{q^2}{4\pi c \kappa^6 R^2} \left | {\bf n} \times \left \{ \left ( {\bf n} - \beta \right ) \times {\dot{\beta}} \right \} \right |^2$

  • Angle Addition and Subtraction Formulae

    • $\begin{aligned} \cos(\alpha + \beta) &= \cos \alpha \cos \beta - \sin \alpha \sin \beta \\ \cos(\alpha - \beta) &= \cos \alpha \cos \beta + \sin \alpha \sin \beta \end{aligned}$
    • $\begin{aligned} \sin(\alpha + \beta) &= \sin \alpha \cos \beta + \cos \alpha \sin \beta \\ \sin(\alpha - \beta) &= \sin \alpha \cos \beta - \cos \alpha \sin \beta \end{aligned}$
    • $\displaystyle{ \begin{aligned} \tan(\alpha + \beta) &= \frac{ \tan \alpha + \tan \beta}{1 - \tan \alpha \tan \beta} \\ \tan(\alpha - \beta) &= \frac{ \tan \alpha - \tan \beta}{1 + \tan \alpha \tan \beta} \end{aligned} }$
    • Apply the formula $\cos(\alpha - \beta) = \cos \alpha \cos \beta + \sin \alpha \sin \beta$:
    • We can thus apply the formula for sine of the difference of two angles: $\sin(\alpha - \beta) = \sin \alpha \cos \beta - \cos \alpha \sin \beta$.

  • Lead-Sheet and Figured-Bass Symbols

    • The most common lead-sheet chord symbols for triads, seventh chords, and standard alterations orembellishments of those chords, along with corresponding thoroughbass figures.

  • Distribution in Frequency and Angle

    • $\displaystyle R {\hat E} (\omega) = \frac{q}{2\pi c} \int_{-\infty}^{\infty} \left [ \frac{\bf n}{\kappa^3} \times \left [ ({\bf n} - \beta ) \times \dot{\beta} \right ]\right ]_\mathrm{ret} e^{i\omega t} d t.$
    • $\displaystyle R {\hat E} (\omega) = \frac{q}{2\pi c} \int_{-\infty}^{\infty} \left [ \frac{\bf n}{\kappa^2} \times \left [ ({\bf n} - \beta ) \times \dot{\beta} \right ]\right ] e^{i\omega (t'+R(t')/c)} d t'.$
    • $\displaystyle R {\hat E} (\omega) = \frac{q}{2\pi c} \int_{-\infty}^{\infty} \left [ \frac{\bf n}{\kappa^2} \times \left [ ({\bf n} - \beta) \times \dot{\beta} \right ]\right ] e^{i\omega (t'-{\bf n}\cdot {\bf r}(t')/c)} d t'.$
    • $\displaystyle \frac{d W}{d\Omega d\omega} = \frac{q^2}{4\pi^2 c} \left | \int_{-\infty}^{\infty} \frac{{\bf n} \times \left [ ({\bf n} - \beta ) \times \dot{\beta} \right ]}{\left ( 1-\beta\cdot {\bf n} \right )^2} e^{i\omega (t'-{\bf n}\cdot {\bf r}(t')/c)} d t' \right |.$
    • $\displaystyle \frac{{\bf n} \times \left [ ({\bf n} - \beta ) \times \dot{\beta} \right ]}{\left ( 1-\beta\cdot {\bf n} \right )^2} = \frac{d}{d t'} \left [ \frac{{\bf n} \times ({\bf n} \times \beta ) }{1-\beta\cdot {\bf n}} \right ].$

  • Beta Coefficient for Portfolios

    • A portfolio's Beta is the volatility correlated to an underlying index.
    • A portfolio's Beta is the volatility correlated to an underlying index.
    • What would the following portfolios have for Beta values?
    • Thus, the portfolio would have a Beta value of 3.
    • Two hypothetical portfolios; what do you think each Beta value is?