A filter assembly includes a filter housing having a longitudinal axis, the filter housing divided into a first filter chamber and a second filter chamber, a first element bottom endplate, a second element top endplate, an intermediate endplate positioned along the longitudinal axis between the second element top endplate and the first element bottom endplate, a first filter element housed within the first filter chamber and comprising first filter media positioned between the first element bottom endplate and the intermediate endplate, and a second filter element housed within the second filter chamber and comprising second filter media positioned between the second element top endplate and the intermediate endplate.

Described are apparatus, systems, and methods of improving cleaning of, e.g., stairs of swimming pools. Automatic swimming pool cleaners (APCs) capable of autonomous movement within water-containing vessels may be utilized to provide enhanced cleaning of sections of the vessels containing stairs or other angled surfaces.

Described are apparatus, systems, and methods of improving cleaning of, e.g., stairs of swimming pools. Automatic swimming pool cleaners (APCs) capable of autonomous movement within water-containing vessels may be utilized to provide enhanced cleaning of sections of the vessels containing stairs or other angled surfaces.

Aspects herein include filter systems including short-range wireless tracking features to detect insertion and/or removal of filter elements from filter systems. In an embodiment, a filtration system is included having a housing including a fluid inlet and a fluid outlet. The housing can define an internal volume. A first filter element can be removably disposed within the housing. A short-range wireless communication tag can be associated with the first filter element. A short-range wireless communication reader can be associated with the housing, the reader configured to wirelessly send data to and receive data from the tag when the reader and the tag are at a distance that is less than or equal to a maximum communication distance. Removal of the first filter element from the housing can cause the distance between the tag and the reader to exceed the maximum communication distance. Other embodiments are also included herein.

Aspects herein include filter systems including short-range wireless tracking features to detect insertion and/or removal of filter elements from filter systems. In an embodiment, a filtration system is included having a housing including a fluid inlet and a fluid outlet. The housing can define an internal volume. A first filter element can be removably disposed within the housing. A short-range wireless communication tag can be associated with the first filter element. A short-range wireless communication reader can be associated with the housing, the reader configured to wirelessly send data to and receive data from the tag when the reader and the tag are at a distance that is less than or equal to a maximum communication distance. Removal of the first filter element from the housing can cause the distance between the tag and the reader to exceed the maximum communication distance. Other embodiments are also included herein.

A filter element has an upstream and downstream side. A filter media assembly of the filter element has an upstream side and a downstream side and has a first filter media layer and a second filter media layer that is adjacent to the first media layer. A substantial portion of the first layer and second layer are uncoupled, and at least one of the first media layer and second media layer comprises binder fiber. The second media layer has a mean flow pore size equal to or smaller than the first media layer. A support layer system is adjacent to the downstream side of the filter media assembly, and a first wire mesh layer is adjacent to the support layer system. At least the first media layer, second media layer, support layer system, and first wire mesh cooperatively define pleats at a pleat packing density of greater than 125%.

A filter element has an upstream and downstream side. A filter media assembly of the filter element has an upstream side and a downstream side and has a first filter media layer and a second filter media layer that is adjacent to the first media layer. A substantial portion of the first layer and second layer are uncoupled, and at least one of the first media layer and second media layer comprises binder fiber. The second media layer has a mean flow pore size equal to or smaller than the first media layer. A support layer system is adjacent to the downstream side of the filter media assembly, and a first wire mesh layer is adjacent to the support layer system. At least the first media layer, second media layer, support layer system, and first wire mesh cooperatively define pleats at a pleat packing density of greater than 125%.

Methods, compositions, and systems for asymmetric semi-nested isothermal nucleotide amplification (ANINA) for the amplification of single-stranded oligonucleotides, the methods, compositions, and systems herein no not require thermal melting and may be used in a point-of-need setting. The methods feature amplification of a target region and production of single stranded amplicons including the target region.

A filter element includes a first end cap, a second end cap, and an intermediate end cap disposed between the first end cap and the second end cap. A ring of first filter media circumscribing a first central cavity is disposed between the first end cap and the intermediate end cap. A ring of second filter media is disposed between the intermediate end cap and the second end cap. The filter element also includes an air-bleed conduit axially extending through the first central cavity and comprising a first portion integrally formed with the first end cap and a second portion integrally formed with the intermediate end cap and configured to connect to the first portion thereby forming a conduit for transmitting fluid.

A filter element includes a first end cap, a second end cap, and an intermediate end cap disposed between the first end cap and the second end cap. A ring of first filter media circumscribing a first central cavity is disposed between the first end cap and the intermediate end cap. A ring of second filter media is disposed between the intermediate end cap and the second end cap. The filter element also includes an air-bleed conduit axially extending through the first central cavity and comprising a first portion integrally formed with the first end cap and a second portion integrally formed with the intermediate end cap and configured to connect to the first portion thereby forming a conduit for transmitting fluid.