The Klenow fragment is a large protein fragment produced when DNA polymerase I from E. coli is enzymatically cleaved by the protease subtilisin. First reported in 1970, it retains the 5 → 3 polymerase activity and the 3’ → 5’ exonuclease activity for removal of precoding nucleotides and proofreading, but loses its 5 → 3 exonuclease activity. The other smaller fragment formed when DNA polymerase I from E. coli is cleaved by subtilisin retains the 5 → 3 exonuclease activity but does not have the other two activities exhibited by the Klenow fragment i.e. 5 → 3 polymerase activity, and 3 → 5 exonuclease activity.
DNA fragmentation is the separation or breaking of DNA strands into pieces. It can be done intentionally by laboratory personnel or by cells, or can occur spontaneously. Spontaneous or accidental DNA fragmentation is fragmentation that gradually accumulates in a cell. It can be measured by e.g. the Comet assay or by the TUNEL assay. Men with sperm motility defects often have high levels of sperm DNA fragmentation. The degree of DNA fragmentation in sperm cells can predict outcomes for in vitro fertilization IVF and its expansion intracytoplasmic sperm injection ICSI. The sperm chromatin dispersion test SCD and TUNEL assay are both effective in detecting sperm DNA damage. Using bright-field microscopy, the SCD test appears to be more sensitive than the TUNEL assay. Its main units of measurement is the DNA Fragmentation Index DFI. A DFI of 20% or more significantly reduces the success rates after ICSI. DNA fragmentation was first documented by Williamson in 1970 when he observed discrete oligomeric fragments occurring during cell death in primary neonatal liver cultures. He described the cytoplasmic DNA isolated from mouse liver cells after culture as characterized by DNA fragments with a molecular weight consisting of multiples of 135 kDa. This finding was consistent with the hypothesis that these DNA fragments were a specific degradation product of nuclear DNA.
The Last Judgment (Bosch triptych fragment)
The Last Judgment is a triptych created by a follower of Hieronymus Bosch. Unlike the other two triptychs with the same name, in Vienna and in Bruges, only a fragment of this one exists today. It resides at the Alte Pinakothek in Munich. After being damaged, this fragment was heavily repainted, then the paint was removed in 1936.
Fragmentation in a technology market happens when a market is composed of multiple highly-incompatible technologies or technology stacks, forcing prospective buyers of a single product to commit to an entire product ecosystem, rather than maintaining free choice of complementary products and services. Two common varieties of fragmentation are market fragmentation and version fragmentation. Fragmentation is the opposite of, and is solved by standardization.
Charge remote fragmentation
IP fragmentation is an Internet Protocol process that breaks packets into smaller pieces, so that the resulting pieces can pass through a link with a smaller maximum transmission unit than the original packet size. The fragments are reassembled by the receiving host. RFC 791 describes the procedure for IP fragmentation, and transmission and reassembly of IP packets. RFC 815 describes a simplified algorithm of the Assembly. The identification field along with the foreign and local Internet address and the Protocol number and the offset field of the fragment along with the fragment and not fragment flags in the IP header addresses are used for fragmentation and reassembly of IP packets. If the receiving host receives a fragmented IP packet, it needs to collect the packet and pass it to a higher level Protocol. The Assembly is meant to happen in the receiving host but in practice it can be done with the help of intermediate router, for example, network address translation NAT may need to reassemble the fragments in order to translate data streams. The details of the mechanism of fragmentation, as well as the overall architectural approach to fragmentation, are different between IPv4 and IPv6.
Single-chain variable fragment
A single-chain variable fragment is not actually a fragment of an antibody, but instead is a fusion protein of the variable regions of the heavy and light chains of immunoglobulins, connected with a short linker peptide of ten to about 25 amino acids. The linker is usually rich in glycine for flexibility, as well as serine or threonine for solubility, and can either connect the N-terminus of the V H with the C-terminus of the V L, or vice versa. This protein retains the specificity of the original immunoglobulin, despite removal of the constant regions and the introduction of the linker. The image to the right shows how this modification usually leaves the specificity unaltered. These molecules were created to facilitate phage display where it is highly convenient to Express the antigen-binding domain as a single peptide. Alternatively, the scfv can be created directly from subclavian heavy and light chains obtained from the hybridoma. ScFvs have many uses, for example, flow cytometry, immunohistochemistry and as antigen binding Domains of artificial T cell receptors. Unlike monoclonal antibodies that are often produced in cultures of mammalian cells, scFvs are more often produced in cultures of bacterial cells such as E. coli.
Fragment novel, a novel by Warren Fahy Fragments: Memories of a Wartime Childhood 1939–1948, a fictional memoir of Holocaust survival by Binjamin Wilkomirski Fragments, a play by Edward Albee .hack//fragment, an online and offline RPG from the.hack video game series
IP fragmentation, a process in computer networking File system fragmentation, the tendency of a file system to lay out the contents of files non-continuously Fragmentation computing, a phenomenon of computer storage Fragmented distribution attack, in computer security