Abstract: Fluorophores are used during the synthesis of oligonucleotides to achieve real-time quality control of the synthesis process. Fluorescence may indicate successful addition of individual nucleotides to a growing oligonucleotide strand or removal of a blocking group. The oligonucleotides may be created by enzymatic synthesis using terminal deoxynucleotidyl transferase (TdT). The synthesis is performed on an addressable array so that oligonucleotides with different sequences are created in parallel on different regions of the array. The oligonucleotide sequences are predetermined and the locations of synthesis on the array are controlled. Observed fluorescence is compared to expected locations of fluorescence as determined by the oligonucleotide sequences and the arrangement on the array. Thus, the fidelity of oligonucleotide synthesis is checked as synthesis proceeds. If a variation is found, a mitigating action is taken such as repeating addition of a species of nucleotide or repeating a deblocking step.

Abstract: Enzymatic polynucleotide synthesis with a template-independent polymerase is used to create multiple polynucleotides having different, arbitrary sequences on the surface of an array. The array provides a spatially-addressable substrate for solid-phase synthesis. Blocking groups are attached to the 3? ends of polynucleotides on the array. Prior to polynucleotide extension, the blocking groups are removed at a selected location on the array. In an implementation, the blocking groups are acyl groups removed with a negative voltage created at an electrode. The array is then incubated with the polymerase and a single species of nucleotide. Nucleotides are incorporated onto the 3? ends of the polynucleotides without blocking groups. Washing removes the polymerase and free nucleotides. To create polynucleotides with different sequences at different locations on the array, the location where the blocking groups are removed and the species of nucleotide may be changed during repeated cycles of synthesis.

Abstract: De novo polynucleotide synthesis is performed with a substrate-bound polymerase. The polymerase is attached to a solid substrate such as a microelectrode array. The polymerase adds nucleotides to growing polynucleotides strands that are also attached to the solid substrate. Spatial control of polymerase activity is achieved by changing the rate of nucleotide polymerization at selected locations on the surface of the solid substrate. The rate of polymerization is changed by inhibiting or promoting activity of the polymerase. In some implementations, activation of electrodes in the microelectrode array changes the rate of nucleotide polymerization. Nucleotides are added to the growing polynucleotide strands at areas where the polymerase is active. By varying the locations where the substrate-bound polymerase is active and the species of nucleotide added, a population of polynucleotides with different, arbitrary sequences is synthesized on the surface of the solid substrate.

Abstract: Multiple polynucleotides having different, arbitrary sequences are synthesized on the surface of an array by spatial control of polymerase activity. The polymerase is a template-independent polymerase such as terminal deoxynucleotidyl transferase (TdT). Spatial control of polymerase activity is implemented by localized changes in redox-pH conditions. A single species of nucleotide is added and incorporated on growing polynucleotide strands at locations on the array where the polymerase is active. A washing step removes the polymerase and free nucleotides. This process may be repeated multiple times changing both the location of polymerase activity and the species of nucleotide thereby synthesizing different polynucleotides in parallel on the surface of the array. Polymerase activity may be regulated by removing a blocking group attached to a His-tag sequence on the polymerase, a change in pH, or release of encapsulated inhibitors.

Abstract: Enzymatic polynucleotide synthesis with a template-independent polymerase is used to create multiple polynucleotides having different, arbitrary sequences on the surface of an array. The array provides a spatially-addressable substrate for solid-phase synthesis. Blocking groups are attached to the 3? ends of polynucleotides on the array. Prior to polynucleotide extension, the blocking groups are removed at a selected location on the array. In an implementation, the blocking groups are acyl groups removed with a negative voltage created at an electrode. The array is then incubated with the polymerase and a single species of nucleotide. Nucleotides are incorporated onto the 3? ends of the polynucleotides without blocking groups. Washing removes the polymerase and free nucleotides. To create polynucleotides with different sequences at different locations on the array, the location where the blocking groups are removed and the species of nucleotide may be changed during repeated cycles of synthesis.

Abstract: Flow stop assemblies are described herein. A flow stop assembly configured to control flow through a tubing includes a flow stop base and a pincher. The flow stop base includes a base wall, at least one pincher guard, a tubing guide, a pincher recess, a pincher protrusion, and a base extension. The pincher is movable relative to the base extension and is configured to move between a flow position and an occlusion position, wherein in the flow position the pincher surface is spaced apart from the pincher protrusion and in the occlusion position, the pincher surface is disposed adjacent to the pincher protrusion and is configured to obstruct flow through the tubing.

Abstract: This disclosure provides electrochemically-cleavable linkers with cleavage potentials that are less than the redox potential of the solvent in which the linkers are used. In some applications, the solvent may be water or an aqueous buffer solution. The linkers may be used to link a nucleotide to a bound group. The linkers include a cleavable group which may be one of a methoxybenzyl alcohol, an ester, a propargyl thioether, or a trichloroethyl ether. The linkers may be cleaved in solvent by generating an electrode potential that is less than the redox potential of the solvent. In some implementations, an electrode array may be used to generate localized electrode potentials which selectively cleave linkers bound to the activated electrode. Uses for the linkers include attachment of blocking groups to nucleotides in enzymatic oligonucleotide synthesis.

Abstract: Multiple polynucleotides having different, arbitrary sequences are synthesized on the surface of an array by spatial control of polymerase activity. The polymerase is a template-independent polymerase such as terminal deoxynucleotidyl transferase (TdT). Spatial control of polymerase activity is implemented by localized changes in redox-pH conditions. A single species of nucleotide is added and incorporated on growing polynucleotide strands at locations on the array where the polymerase is active. A washing step removes the polymerase and free nucleotides. This process may be repeated multiple times changing both the location of polymerase activity and the species of nucleotide thereby synthesizing different polynucleotides in parallel on the surface of the array. Polymerase activity may be regulated by removing a blocking group attached to a His-tag sequence on the polymerase, a change in pH, or release of encapsulated inhibitors.

Abstract: An animal feces collection assembly for automatically collecting animal feces in a yard includes a cart that has a drive unit integrated into the cart and a collection space is integrated into the cart. The cart has a ramp is positionable in an open position or closed position. A collection unit is movably integrated into the cart to engage animal feces that have been collected on the ramp. The collection unit is actuated into a retracted condition to urge the animal feces upwardly along the ramp and into the collection space. A camera is coupled to the cart thereby facilitating the camera to capture footage of the yard view the animal feces. The drive unit is actuated to drive the cart toward the animal feces and the collection unit is actuated into an extended condition when the cart approaches the animal feces to automatically collect the animal feces from the yard.

Abstract: Flow stop assemblies are described herein. A flow stop assembly configured to control flow through a tubing includes a flow stop base and a pincher. The flow stop base includes a base wall, at least one pincher guard, a tubing guide, a pincher recess, a pincher protrusion, and a base extension. The pincher is movable relative to the base extension and is configured to move between a flow position and an occlusion position, wherein in the flow position the pincher surface is spaced apart from the pincher protrusion and in the occlusion position, the pincher surface is disposed adjacent to the pincher protrusion and is configured to obstruct flow through the tubing.

Abstract: This disclosure provides electrochemically-cleavable linkers with cleavage potentials that are less than the redox potential of the solvent in which the linkers are used. In some applications, the solvent may be water or an aqueous buffer solution. The linkers may be used to link a nucleotide to a bound group. The linkers include a cleavable group which may be one of a methoxybenzyl alcohol, an ester, a propargyl thioether, or a trichloroethyl ether. The linkers may be cleaved in solvent by generating an electrode potential that is less than the redox potential of the solvent. In some implementations, an electrode array may be used to generate localized electrode potentials which selectively cleave linkers bound to the activated electrode. Uses for the linkers include attachment of blocking groups to nucleotides in enzymatic oligonucleotide synthesis.

Abstract: This disclosure provides electrochemically-cleavable linkers with cleavage potentials that are less than the redox potential of the solvent in which the linkers are used. In some applications, the solvent may be water or an aqueous buffer solution. The linkers may be used to link a nucleotide to a bound group. The linkers include a cleavable group which may be one of a methoxybenzyl alcohol, an ester, a propargyl thioether, or a trichloroethyl ether. The linkers may be cleaved in solvent by generating an electrode potential that is less than the redox potential of the solvent. In some implementations, an electrode array may be used to generate localized electrode potentials which selectively cleave linkers bound to the activated electrode. Uses for the linkers include attachment of blocking groups to nucleotides in enzymatic oligonucleotide synthesis.

Abstract: The present application discloses a climbing robot (10) for climbing ferrous structures (30), a dual gear pivot mechanism for a climbing robot (10), and a method of controlling a climbing robot (10) for climbing ferrous structures (30). The climbing robot (10) comprises three drive units (12, 14, 16) coupled together and the central drive unit is coupled to a pivot mechanism (24). Each drive unit (12, 14, 16) comprises a wheel arrangement (13, 15, 17) comprising at least one wheel configured to adhere to a ferrous tower (30), and each wheel is independently controllable. A first wheel arrangement (13) is the wheel arrangement of one of the three drive units (12, 14, 16). A second wheel arrangement (15) is the wheel arrangement of another one of the three drive units (12, 14, 16).

Abstract: This disclosure provides electrochemically-cleavable linkers with cleavage potentials that are less than the redox potential of the solvent in which the linkers are used. In some applications, the solvent may be water or an aqueous buffer solution. The linkers may be used to link a nucleotide to a bound group. The linkers include a cleavable group which may be one of a methoxybenzyl alcohol, an ester, a propargyl thioether, or a trichloroethyl ether. The linkers may be cleaved in solvent by generating an electrode potential that is less than the redox potential of the solvent. In some implementations, an electrode array may be used to generate localized electrode potentials which selectively cleave linkers bound to the activated electrode. Uses for the linkers include attachment of blocking groups to nucleotides in enzymatic oligonucleotide synthesis.

Abstract: An animal feces collection assembly for automatically collecting animal feces in a yard includes a cart that has a drive unit integrated into the cart and a collection space is integrated into the cart. The cart has a ramp is positionable in an open position or closed position. A collection unit is movably integrated into the cart to engage animal feces that have been collected on the ramp. The collection unit is actuated into a retracted condition to urge the animal feces upwardly along the ramp and into the collection space. A camera is coupled to the cart thereby facilitating the camera to capture footage of the yard view the animal feces. The drive unit is actuated to drive the cart toward the animal feces and the collection unit is actuated into an extended condition when the cart approaches the animal feces to automatically collect the animal feces from the yard.

Abstract: Electrically controlled hybridization is used to selectively assemble oligonucleotides on the surface of a microelectrode array. Controlled activation of individual electrodes in the microelectrode array attracts oligonucleotides in solution to specific regions of the array where they hybridize to other oligonucleotides anchored on the array. The oligonucleotides that hybridize may provide locations for subsequent oligonucleotides to hybridize. The active electrodes and the oligonucleotides in solution may be varied during each round of synthesis. This allows for multiple oligonucleotides each with different and specific sequences to be created in parallel. This is accomplished without the use of phosphoramidite chemical synthesis or template-independent DNA polymerase enzymatic synthesis. Oligonucleotides created with these techniques may be used to encode digital data. Fully assembled oligonucleotides may be separated from the array and sequenced, stored, or otherwise processed.

Abstract: De novo polynucleotide synthesis is performed with a substrate-bound polymerase. The polymerase is attached to a solid substrate such as a microelectrode array. The polymerase adds nucleotides to growing polynucleotides strands that are also attached to the solid substrate. Spatial control of polymerase activity is achieved by changing the rate of nucleotide polymerization at selected locations on the surface of the solid substrate. The rate of polymerization is changed by inhibiting or promoting activity of the polymerase. In some implementations, activation of electrodes in the microelectrode array changes the rate of nucleotide polymerization. Nucleotides are added to the growing polynucleotide strands at areas where the polymerase is active. By varying the locations where the substrate-bound polymerase is active and the species of nucleotide added, a population of polynucleotides with different, arbitrary sequences is synthesized on the surface of the solid substrate.

Abstract: Electrically controlled hybridization is used to selectively assemble oligonucleotides on the surface of a microelectrode array. Controlled activation of individual electrodes in the microelectrode array attracts oligonucleotides in solution to specific regions of the array where they hybridize to other oligonucleotides anchored on the array. The oligonucleotides that hybridize may provide locations for subsequent oligonucleotides to hybridize. The active electrodes and the oligonucleotides in solution may be varied during each round of synthesis. This allows for multiple oligonucleotides each with different and specific sequences to be created in parallel. This is accomplished without the use of phosphoramidite chemical synthesis or template-independent DNA polymerase enzymatic synthesis. Oligonucleotides created with these techniques may be used to encode digital data. Fully assembled oligonucleotides may be separated from the array and sequenced, stored, or otherwise processed.

Abstract: A switchable hydrophilic surface is created by attaching electrochemically switchable hydrophilicity polymers to the surface of a microelectrode array. Ferrocene polymers are one example of electrochemically switchable hydrophilicity polymers. Activation of electrodes in the microelectrode array changes the oxidation state of metal ions which switches the polymers between hydrophobic and hydrophilic conformations. Selective activation of electrodes can create patterns of wettability on the microelectrode array that may be varied in real time. The switchable hydrophilic surface may be used to control solid-phase synthesis of polymers. Growing polymers may be selectively extended at locations on the microelectrode array that are hydrophilic. The pattern of hydrophobic and hydrophilic regions can be changed during sequential rounds of synthesis to create a variety of different polymers at different locations on the surface of the microelectrode array.

Abstract: A universal template strand built with universal base analogs is used as a template for polynucleotide synthesis. The universal template strand can hybridize to any sequence of nucleotides. A new polynucleotide is synthesized by using a polymerase to extend a primer hybridized to the universal template strand. Unlike primer extension in polymerase chain reactions, base pairing with nucleotides in the template strand does not specify the sequence of the new polynucleotide. Instead, the sequence of the new polynucleotide is specified by the order of addition of protected nucleotides. After addition of a single species of protected nucleotide, the blocking group is removed and another protected nucleotide is added. The order of nucleotide addition can be varied to create any sequence. After synthesis, the polynucleotide can be dehybridized from the universal template strand. The universal template strand may then be reused to synthesize a different polynucleotide.