Abstract: A method of manufacturing a substrate with reduced threading dislocation density is disclosed, which comprises: (i) at a first temperature, forming a first layer of wafer material on a semiconductor substrate, the first layer arranged to be doped with a first concentration of at least one dopant that is different to the wafer material; and (ii) at a second temperature higher than the first temperature, forming a second layer of the wafer material on the first layer to obtain the substrate, the second layer arranged to be doped with a progressively decreasing concentration of the dopant during formation, the doping configured to be decreased from the first concentration to a second concentration. The wafer material and dopant are different to silicon. A related substrate is also disclosed.

Abstract: An acoustic resonator includes a wafer and a first phononic crystal disposed on the wafer to define an acoustic waveguide so as to propagate an acoustic wave along a propagation direction. The first phononic crystal includes a first two-dimensional (2D) array of metal stripes having a first period on the propagation direction. The apparatus also includes a second phononic crystal and a third phononic crystal disposed on two sides of the first phononic crystal and having a different period from the first period. The second phononic crystal and the wafer define a first reflector to reflect the acoustic wave. The third phononic crystal and the wafer define a second reflector to reflect the acoustic wave.

Abstract: The present invention provides methods of inducing proliferation of and/or differentiating cells comprising contacting cells with compounds within the methods of the invention. The present invention further provides cells obtainable by the methods of the invention. Liver disease affects more than 500 million people worldwide. Organ transplantation is the gold standard for treatment of liver failure, but organ shortages are acute.

Abstract: A neural drug delivery system is disclosed. In an embodiment, the system includes two or more microtubes, each having a distal end, a proximal end, and elongate channel body extending therebetween; an electrode having a distal end, a proximal end, and elongate body extending therebetween; an elongate carrying template supporting the microtubes and the electrode in an aligned stack; and an annular needle having a distal end and a proximal end, and housing the carrying template, the microtubes, and the electrode. The system may include at least one pump fluidically connected to the proximal end(s) of one or more of the microtubes. The pump may be configured to deliver a fluid drug on demand through the elongate channel body and out of the distal end of the microtubes.

Abstract: The invention in some aspects relates to high throughput methods and devices for evaluating mechanical, morphological, kinetic, rheological or hematological properties of cells, such as blood cells under regulated gas conditions. In some aspects, the invention relates to methods and devices for diagnosing and/or characterizing a condition or disease in a subject by measuring a property of a cell from the subject, under controlled gas conditions.

Abstract: A method and microfluidic device useful for isolating microbes from a blood sample which includes introducing the blood sample into the sample inlet of a spiral microfluidic device; and introducing a second fluid into the sheath inlet of the microfluidic device, wherein the spiral channel terminates in a microbe outlet and a waste outlet, and wherein the spiral channel includes a length, height, and a width that define an aspect ratio adapted to isolate any microbes present in the sample along a first portion of the spiral channel terminating at the microbe outlet, and to isolate red blood cells and leukocytes along a second portion of the spiral channel terminating at the waste outlet; and collecting the microbes from the microbe outlet, thereby isolating the microbes.

Abstract: When imaging bright objects, a conventional detector array can saturate, making it difficult to produce an image with a dynamic range that equals the scene's dynamic range. Conversely, a digital focal plane array (DFPA) with one or more m-bit counters can produce an image whose dynamic range is greater than the native dynamic range. In one example, the DFPA acquires a first image over a relatively brief integration period at a relatively low gain setting. The DFPA then acquires a second image over longer integration period and/or a higher gain setting. During this second integration period, counters may roll over, possibly several times, to capture a residue modulus 2m of the number of counts (as opposed to the actual number of counts). A processor in or coupled to the DFPA generates a high-dynamic range image based on the first image and the residues modulus 2m.

Abstract: A semiconductor structure includes at least two substrate layers, each of the at least two substrate layers having first and second opposing surfaces and a plurality of electrical connections extending between the first and second surfaces. The semiconductor structure also includes a substrate joining layer disposed between and coupled to the second surface of a first one of the at least two substrate layers and the first surface of a second one of the at least two substrate layers. The substrate joining layer includes at least one integrated circuit (IC) structure disposed between the first and second surfaces of said substrate joining layer. A corresponding method for fabricating a semiconductor structure is also provided.

Abstract: Described herein are systems, methods, and apparatus for automatically identifying and recovering individual cells of interest from a sample of biological matter, e.g., a biological fluid. Also described are methods of enriching a cell type of interest. These systems, methods, and apparatus allow for coordinated performance of two or more of the following, e.g., all with the same device, thereby enabling high throughput: cell enrichment, cell identification, and individual cell recovery for further analysis (e.g., sequencing) of individual recovered cells.

Abstract: T-peel test fixture for a vertical test machine. The test fixture includes an upper grip for holding an arm of a peel specimen that has a hangover tail and a lower grip for holding the other arm of the peel specimen. A first rack is connected to a support hanger. The upper grip and the first rack move in a vertical direction at a selected speed. A second rack including a support plate located to support the specimen hangover tail is driven in the vertical direction at one-half the selected speed. The fixture thus supports the hangover tail so that symmetry is maintained with respect to gravity to suppress the interfering effect of gravity on a peel test.

Abstract: Compliant leak detection system. The system includes structure adapted to support at least two rows of leak detection leaves, each leak detection leaf supported by an arm pivotally attached to the structure and urged outwardly by a torsion spring into contact with a pipe wall so as to adjust for changes in pipe diameter. The leak detection leaf includes a rigid support and a flexible member such that suction from a leak will cause the flexible member to contact the pipe wall and put a drag force on the structure. An axial force transmitting drum measures the drag force to indicate presence of a leak.

Abstract: High-temperature superconducting (HTS) devices and methods are disclosed. An HTS cable subassembly has a rectangular shaped cross section. The subassembly includes a stack of tapes formed of a superconducting material, and a cable subassembly wrapper wrapped around the stack of tapes. The tapes in the stack are slidably arranged in a parallel fashion. A cable assembly is formed of a cable assembly wrapper formed of a second non-superconducting material disposed around an n×m array of cable subassemblies. Within a cable assembly, a first cable subassembly of the array of subassemblies is oriented substantially perpendicular to a second cable subassembly with regard to the plurality of tapes. A compound-cable assembly is formed by joining two or more cable assemblies. A high-temperature superconducting magnet is formed of a solenoidal magnet as well as dipole and quadrupole magnets wound of a cable subassembly, a cable assembly, and/or a compound cable assembly.

Abstract: A system for training a neural network model, the neural network model comprising a plurality of layers including a first hidden layer associated with a first set of weights, the system comprising at least one computer hardware processor programmed to perform: obtaining training data; selecting a unitary rotational representation for representing a matrix of the first set weights, the selected unitary rotational representation comprising a plurality of parameters; training the neural network model using the training data using an iterative neural network training algorithm to obtain a trained neural network model, each iteration of the iterative neural network training algorithm comprising: updating values of the plurality of parameters in the selected unitary rotational representation for representing the matrix of the set of weights for the at least one hidden layer, and saving the trained neural network model.

Abstract: Battery separators for lithium-air batteries are provided. In some embodiments, a lithium-air battery may comprise one or more electrochemical cells including an anode, a cathode, an electrolyte, and a battery separator positioned between the anode and the cathode. The battery separator may comprise a porous membrane having a lithium ion conductive film on at least a portion of the porous membrane. The lithium ion conductive film may comprise layers designed to impart beneficial properties to the porous membrane and/or battery, such as resistance to dendrite formation, while having relatively minimal or no adverse effects on one or more important properties of the porous membrane (e.g., ionic conductivity, electrolyte permeability, weight, mechanical stability) and/or the overall battery.

Abstract: A method for lithographic patterning of thin films. A thin film is deposited on a substrate and the film is exposed to optical energy from a focused laser to induce a thermal gradient in the film by optical absorption. The film is softened through a melting or glass transition process and the thermal gradient induces a directional dewetting down the thermal gradient. The invention permits developer free positive tone lithography by thermal direct write and also metrology of the thin film by the morphology of the resultant features.

Abstract: A method of imaging a scene includes generating a temporally varying optical intensity pattern from at least one continuous wave (CW) light beam. The method also includes illuminating at least one portion of the scene with the temporally varying optical intensity pattern so as to cause a photon to scatter or reflect off the at least one portion of the scene. The photon reflected or scatted from the at least one portion of the scene is detected using a single-photon detector. Based on the temporally varying optical intensity pattern and a time of flight of the photon detected, a distance between the single-photon detector and the at least one portion of the scene is estimated.

Abstract: A circuit includes a reconfigurable rectifier, a voltage balancer, and a pair of converters. The reconfigurable rectifier includes an ac input port and three output ports. In a first configuration, the reconfigurable rectifier can deliver power at a first output port and, in a second configuration, to at least a second output port. The voltage balancer includes first and second ports coupled to second and third output ports of the reconfigurable rectifier and is configured to balance received voltage at the first and second ports. The first converter has an input coupled to the first port of the voltage balancer and an output at which a first converted voltage signal is provided. The second converter has an input coupled to the second port of the voltage balancer and an output at which a second converted voltage signal is provided.

Abstract: Loud sounds with fast rise times, like gunfire and explosions, can cause noise-induced hearing loss (NIHL). Unfortunately, current models do not adequately explain how impulsive sounds cause NIHL, which makes it difficult to predict and prevent NIHL on battlefields and other hostile or rugged environments. Fortunately, the impulsive sounds experienced by soldiers and others working in rugged environments can be recorded using a compact, portable system that acquires, digitizes, and stores high-bandwidth audio data. An example of this system can be mounted on a helmet or other article and used to record hours of audio data at a bandwidth of 20 kHz or higher, which is broad enough to capture sounds with rise times less than 50 ms. An analog-to-digital converter (ADC) digitizes these broadband audio signals at rate of 40 kHz or higher to preserve the impulse information. A processor transfers the digitized samples from a buffer to a memory card for later retrieval using an interrupt-driven processing technique.

Abstract: Double-clad optical fibers with polymer outer coatings are used in fiber amplifiers and fiber lasers to guide and amplify light. As the optical power increases, the optical fibers must dissipate more heat. Unfortunately, it is difficult to dissipate heat through a polymer cladding, especially at high altitude, without introducing phase noise in the optical signal. To overcome this problem, the inventors have realized metallized polymer-clad optical fibers with superior heat dissipation characteristics than conventional polymer-clad optical fibers. An example metallized polymer-clad optical fiber includes a thin chrome layer that is vacuum-deposited onto the polymer cladding at low temperature, then electroplated with a thicker copper layer. In operation, the copper layer dissipates heat from within the fiber's core and claddings via a heatsink, enabling the fiber to guide and amplify high-power optical signals at high altitude.

Abstract: A device for thermal energy harvesting can use pulsed heat.