摘要:
A polycation capable of forming a complex with a nucleic acid for carriage thereof. The polycation comprising at least one cyclic compound having a cavity. A polymer backbone is threaded into the cavity of the cyclic compound. A pair of bulky moieties cap the terminals of the polymer backbone to inhibit dethreading of the cyclic compound from the polymer backbone. In use, the net positive charge of said polycation enables a complex to form with nucleic acid.
摘要:
A polycation capable of forming a complex with a nucleic acid for carriage thereof. The polycation comprising at least one cyclic compound having a cavity. A polymer backbone is threaded into the cavity of the cyclic compound. A pair of bulky moieties cap the terminals of the polymer backbone to inhibit dethreading of the cyclic compound from the polymer backbone. In use, the net positive charge of said polycation enables a complex to form with nucleic acid.
摘要:
A branched polyamine comprises about 8 to about 12 backbone tertiary amine groups, about 18 to about 24 backbone secondary amine groups, a positive number n′ greater than 0 of backbone terminating primary amine groups, and a positive number q greater than 0 of backbone terminating carbamate groups of formula (2): wherein (n′+q) is a number equal to about 8 to about 12, the starred bond of formula (2) is linked to a backbone nitrogen of the branched polyamine, L′ is a divalent linking group comprising 3 to 30 carbons, and q/(n′+q)×100% equals about 9% to about 40%.
摘要:
A method and system for optimizing resource usage in an information retrieval system. Meta information in query results describes data items identified by identifiers. A chunk of the identifiers and a set of meta information are loaded into a first cache and a second cache, respectively. A portion of the set of meta information is being viewed by a user. The portion describes a data item identified by an identifier included in the chunk and in a sub-chunk of identifiers that identifies data items described by the set of meta information. If a position of the identifier in the sub-chunk satisfies a first criterion, then a second set of meta information is preloaded into the second cache. If a position of the identifier in the chunk satisfies a second criterion, then a second chunk of the identifiers is preloaded into the first cache.
摘要:
A covalently crosslinked hydrogel comprises a) three or more divalent poly(alkylene oxide) chains P′ covalently linked at respective first end units to a branched first core group C′, b) three or more divalent poly(alkylene oxide) chains P″ covalently linked at respective first end units to a branched second core group C″, the chains P″ comprising respective second end units which are covalently linked to between 0% and 100% of respective second end units of chains P′ by divalent linking groups L″, and c) at least one pendant cationic block copolymer chain A′-B′. A′-B′ comprises i) a divalent block A′ comprising a poly(alkylene oxide) backbone chain having an end unit covalently linked to a second end unit of one of the chains P′ by a divalent linking group L′, and ii) a monovalent block B′ comprising a first repeat unit, the first repeat unit comprising a backbone carbonate group and a cationic side chain group.
摘要:
A method and system for optimizing resource usage in an information retrieval system. Meta information in query results describes data items identified by identifiers. A chunk of the identifiers and a set of meta information are loaded into a first cache and a second cache, respectively. A portion of the set of meta information is being viewed by a user. The portion describes a data item identified by an identifier included in the chunk and in a sub-chunk of identifiers that identifies data items described by the set of meta information. If a position of the identifier in the sub-chunk satisfies a first criterion, then a second set of meta information is preloaded into the second cache. If a position of the identifier in the chunk satisfies a second criterion, then a second chunk of the identifiers is preloaded into the first cache.
摘要:
A branched polyamine comprises about 45 to about 70 backbone tertiary amine groups, about 90 to about 140 backbone secondary amine groups, a positive number n′ greater than 0 of backbone terminating primary amine groups, and a positive number q greater than 0 of backbone terminating carbamate groups of formula (2): wherein (n′+q) is a number equal to about 45 to about 70, the starred bond of formula (2) is linked to a backbone nitrogen of the branched polyamine, L′ is a divalent radical comprising 3 to 30 carbons, and q/(n′+q)×100% equals about 9% to about 47%.
摘要:
A branched polyamine comprises about 45 to about 70 backbone tertiary amine groups, about 90 to about 140 backbone secondary amine groups, a positive number n′ greater than 0 of backbone terminating primary amine groups, and a positive number q greater than 0 of backbone terminating carbamate groups of formula (2): wherein (n′+q) is a number equal to about 45 to about 70, the starred bond of formula (2) is linked to a backbone nitrogen of the branched polyamine, L′ is a divalent radical comprising 3 to 30 carbons, and q/(n′+q)×100% equals about 9% to about 47%.
摘要:
Embodiments of the invention provide a device called a “G-Fresnel” device that performs the functions of both a linear grating and a Fresnel lens. We have fabricated the G-Fresnel device by using PDMS based soft lithography. Three-dimensional surface profilometry has been performed to examine the device quality. We have also conducted optical characterizations to confirm its dual focusing and dispersing properties. The G-Fresnel device can be useful for the development of miniature optical spectrometers as well as emerging optofluidic applications. Embodiments of compact spectrometers using diffractive optical elements are also provided. Theoretical simulation shows that a spectral resolution of approximately 1 nm can be potentially achieved with a millimeter-sized G-Fresnel. A proof-of-concept G-Fresnel-based spectrometer with subnanometer spectral resolution is experimentally demonstrated.
摘要:
A biodegradable block copolymer is disclosed, comprising a hydrophilic block derived from a polyether alcohol; and a hydrophobic block comprising a first repeat unit derived by ring opening polymerization of a first cyclic carbonyl monomer initiated by the polyether alcohol, the first repeat unit comprising a side chain moiety comprising a functional group selected from the group consisting of urea groups, a carboxylic acid groups, and mixtures thereof. No side chain of the hydrophobic block comprises a covalently bound biologically active material. The block copolymer self-assembles in water forming micelles suitable for sequestering a biologically active material by a non-covalent interaction, and the block copolymer is 60% biodegraded within 180 days in accordance with ASTM D6400.