• Organic Chemistry, Biochemistry

    Organic Chemistry, Biochemistry

    Organic molecules are molecules that contain carbon and hydrogen. All living things contain these organic molecules: carbohydrates, lipids, proteins, and nucleic acids. These molecules are often called macromolecules because they may be very large, containing thousands of carbon and hydrogen atoms and because they are typically composed of many smaller molecules bonded together. These four macromolecules will be discussed in the second half...

     23 p pdu 20/10/2012 121 3

  • Fungi

    Fungi

    Fungi (kingdom Fungi) are heterotrophs. They cannot manufacture their own food as photosynthetic organisms can. Most species of fungi are saprotrophic; they decompose dead matter. Many are parasitic; they obtain nutrients from living organisms. Fungi are the principle decomposers in every ecosystem. They can break down most organic compounds including lignin, a compound that is a major component of wood and is very difficult to break down or...

     15 p pdu 20/10/2012 126 2

  • DNA

    DNA

    DNA The Search to Identify the Genetic Material Discovery of Nucleic Acids - Friedrich Miescher, 1869 Miescher isolated the nuclei of white blood cells obtained from pus cells. His experiments revealed that nuclei contained a chemical that contained nitrogen and phosphorus but no sulfur. He called the chemical nuclein because it came from nuclei. It later became known as nucleic acid. Proteins Produce Genetic Traits - Archibald Garrod, 1909...

     21 p pdu 20/10/2012 214 1

  • Control of Gene Expression

    Control of Gene Expression

    By switching genes off when they are not needed, cells can prevent resources from being wasted. There should be natural selection favoring the ability to switch genes on and off. Complex multicellular organisms are produced by cells that switch genes on and off during development. A typical human cell normally expresses about 3% to 5% of its genes at any given time. Cancer results from genes that do not turn off properly. Cancer cells have...

     23 p pdu 20/10/2012 112 1

  • Cells

    Cells

    Notice that the larger cube has more surface area and more volume but less surface area for each cubic centimeter of volume. For any given geometric object (cubes, spheres, etc.), smaller objects have a greater surface to volume ratio (surface:volume) than larger objects of the same shape. Every cell is surrounded by a plasma membrane (discussed below and in the next chapter). Most cells are very small and therefore have a high ratio of...

     45 p pdu 20/10/2012 101 1

  • Magneto-optical trapping of diatomic molecules

    Magneto-optical trapping of diatomic molecules

    The development of the magneto-optical trap revolutionized the fields of atomic and quantum physics by providing a simple method for the rapid production of ultracold, trapped atoms. A similar technique for producing a diverse set of dense, ultracold diatomic molecular species will likewise transform the study of strongly interacting quantum systems, precision measurement, and physical chemistry. We demonstrate one- and two-dimensional...

     13 p pdu 25/09/2012 89 1

  • Photoproduction of η ′ mesons off nuclei and their properties in the nuclear medium

    Photoproduction of η ′ mesons off nuclei and their properties in the nuclear medium

    We study the photoproduction of $\eta^\prime$ mesons from nuclei near the threshold within the collision model based on the nuclear spectral function. The model takes properly into account both primary photon-nucleon and secondary pion-nucleon $\eta^\prime$ production processes as well as the effect of the nuclear $\eta^\prime$ mean-field potential on these processes. We find that the secondary pion-induced reaction channel ${\pi}N \to...

     17 p pdu 25/09/2012 94 1

  • Electromagnetic form factors of the nucleon in effective field theory

    Electromagnetic form factors of the nucleon in effective field theory

    We calculate the electromagnetic form factors of the nucleon to third chiral order in manifestly Lorentz-invariant effective field theory. The ρ and ω mesons as well as the ∆(1232) resonance are included as explicit dynamical degrees of freedom. To obtain a self-consistent theory with respect to constraints we consider the proper relations among the couplings of the effective Lagrangian. For the purpose of generating a systematic power...

     26 p pdu 25/09/2012 127 1

  • Investigation of the reaction 74Ge(p,gamma)75As using the in-beam method to improve reaction network predictions for p nuclei

    Investigation of the reaction 74Ge(p,gamma)75As using the in-beam method to improve reaction network predictions for p nuclei

    A measurement of 74Ge(p,gamma)75As at low proton energies, inside the astrophysically relevant energy region, is important in several respects. The reaction is directly important as it is a bottleneck in the reaction flow which produces the lightest p nucleus 74Se. It is also an important addition to the data set required to test reaction-rate predictions and to allow an improvement in the global p+nucleus optical potential required in such...

     14 p pdu 25/09/2012 84 1

  • Computability of the causal boundary by using isocausality

    Computability of the causal boundary by using isocausality

    Computability of the causal boundary by using isocausalityar Recently, a new viewpoint on the classical c-boundary in Mathematical Relativity has been developed, the relations of this boundary with the conformal one and other classical boundaries have been analyzed, and its computation in some classes of spacetimes, as the standard stationary ones, has been carried out. In the present paper, we consider the notion of isocausality given by...

     43 p pdu 25/09/2012 89 1

  • Metric Properties of the Fuzzy Sphere

    Metric Properties of the Fuzzy Sphere

    The fuzzy sphere, as a quantum metric space, carries a sequence of metrics which we describe in detail. We show that the Bloch coherent states, with these spectral distances, form a sequence of metric spaces that converge to the round sphere in the high-spin limit. It is common practice in several fields to "approximate: a manifold with a finite or countable subset of its points. A typical example in particle physics is the study of quantum...

     26 p pdu 25/09/2012 103 1

  • WILD QUOTIENT SURFACE SINGULARITIES WHOSE DUAL GRAPHS ARE NOT STAR-SHAPED

    WILD QUOTIENT SURFACE SINGULARITIES WHOSE DUAL GRAPHS ARE NOT STAR-SHAPED

    We obtain some results that answer certain questions of Lorenzini on wild quotient singularities in dimension two. Using Kato’s theory of log structures and log regularity, we prove that the dual graph of exceptional curves on the resolution of singularities contains at least one node. Furthermore, we show that diagonal quotients for Hermitian curves by analogues of Heisenberg groups lead to examples of wild quotient singularities where the...

     35 p pdu 25/09/2012 83 1

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