Abstract: Methods, systems, and devices are disclosed for an efficient hardware architecture to implement gradient boosted trees for detecting biological conditions. For example, a method of detecting a biological condition includes receiving, by a device, a plurality of physiological signals from a plurality of input channels of the device, selecting, based on a trained prediction model, one or more input channels from the plurality of input channels, converting the one or more physiological signals received from the one or more input channels to one or more digital physiological signals, identifying, by using the plurality of gradient boosted decision trees, the selected characteristic in the one or more digital physiological signals, and determining a presence of a physiological condition based on an addition of the output values obtained from the plurality of gradient boosted decision trees.

Abstract: An optoelectronic device for quadrature-amplitude modulation (QAM) and a method of modulating light according to the same. The device comprising: an input waveguide; two intermediate waveguides, each coupled to the input waveguide via an input coupler; and an output waveguide, coupled to each of the intermediate waveguides via an output coupler; wherein each intermediate waveguide includes a modulating component connected in series with a phase shifting component, and each modulating component is connected to a respective electronic driver, the electronic drivers together being operable to produce a QAM-N modulated output from light entering the device from the input waveguide.

Abstract: An optical signal modulator (modulator) includes, in part, a first multitude of diodes coupled in parallel and disposed along an outer periphery of the optical ring of the modulator, a second multitude of diodes coupled in parallel and disposed along the outer periphery of the optical ring, and a doped region adapted to supply heat to the optical ring. A pair of current sources supply substantially constant currents to the first and second multitude of diodes to generate a pair of electrical signals. The modulator further includes, in part, a control circuit adapted to control the temperature of the optical ring in accordance with the pair electrical signals. To achieve this, the control circuit varies the voltage applied to the doped region to vary the supplied heat. Alternatively, the control circuit applies a voltage to the optical ring to maintain a substantially constant resonant wavelength in the optical ring.

Abstract: A differential optical modulator includes, in part, a splitter splitting an incoming optical signal into first and second input signals, a first variable coupler generating a first differential output signal in response to the first input signal, and a second variable coupler generating a second differential output signal in response to the second input signal. The first variable coupler includes, in part, first and second couplers and a phase shifter disposed therebetween. The first coupler generates a pair of internal signals in response to the first input signal. The second coupler generates the first differential output signal. The second variable coupler includes, in part, third and fourth couplers and a phase shifter disposed therebetween. The third coupler generates a pair of internal signals in response to the second input signal. The fourth coupler generates the second differential output signal.

Abstract: A three dimensional magnetic sensor attached to a surgical nail is located based on an applied monotonic magnetic field gradient. Another three dimensional magnetic sensor locates a surgical drill. A display generates a real time image of the relative alignment of the surgical drill and of the surgical nail, allowing a surgeon to repair bone fractures.

Abstract: Methods and apparatuses for sensing biological functions are disclosed. Sensors can be implanted in an organ, such as the brain, and a magnetic field gradient applied to the biological tissue. The field causes the sensors to have different resonant frequencies allowing their spatial localization. The sensors can harvest power from the external coils to be able to retransmit data.

Abstract: A smart cage includes radiofrequency transceivers and tags attached to laboratory animals. The tags include sensors to detect monitorable conditions of the laboratory animals. The sensors include working electrodes, counter electrodes, reference electrodes, and potentiostats. The top surface of the electrodes is coated with ionophores or enzymes which detect the monitorable conditions of the laboratory animals.

Abstract: A miniature, low power electronic pressure sensor with a first, oil-filled chamber to protect its microelectromechanical systems (MEMS) pressure sensitive membrane and a second chamber filled with saline or body fluids connected by tube into an organ in the body, such as an eyeball, that needs pressure sensing, is described. The tube carries pressure from a sensitive area within the organ to the electronic pressure sensor. The pressure sensor may communicate wirelessly with external readers and pass data to a server or other computer. Running alongside the tube is another tube for draining and pressure relief. The tubes, or cannulas, can share an opening into the organ in order to minimize the number of holes needed. The tubes may be molded into a single oval cross section, combined coaxially, or share a lumen for a portion that enters the wall of an organ so as to promote healing.

Abstract: Methods and apparatuses for sensing biological functions are disclosed. Sensors can be implanted in an organ, such as the brain, and a magnetic field gradient applied to the biological tissue. The field causes the sensors to have different resonant frequencies allowing their spatial localization. The sensors can harvest power from the external coils to be able to retransmit data.

Abstract: Methods and apparatuses for sensing biological functions are disclosed. Sensors can be implanted in an organ, such as the brain, and a magnetic field gradient applied to the biological tissue. The field causes the sensors to have different resonant frequencies allowing their spatial localization. The sensors can harvest power from the external coils to be able to retransmit data.

Abstract: An integrated optical modulator includes, in part, a pair of waveguides and an inductor. The first waveguide is adapted to receive an incoming optical signal. The second waveguide includes a portion placed in proximity of the first waveguide so as to enable the incoming optical signal travelling in the first waveguide to couple to the second waveguide. The second waveguide comprises a p-n junction. The inductor has a first terminal coupled to the p-n junction and a second terminal coupled to a contact pad. The second waveguide has a circular shape. The inductor optionally has a spiral shape.

Abstract: An optical signal modulator (modulator) includes, in part, a first multitude of diodes coupled in parallel and disposed along an outer periphery of the optical ring of the modulator, a second multitude of diodes coupled in parallel and disposed along the outer periphery of the optical ring, and a doped region adapted to supply heat to the optical ring. A pair of current sources supply substantially constant currents to the first and second multitude of diodes to generate a pair of electrical signals. The modulator further includes, in part, a control circuit adapted to control the temperature of the optical ring in accordance with the pair electrical signals. To achieve this, the control circuit varies the voltage applied to the doped region to vary the supplied heat. Alternatively, the control circuit applies a voltage to the optical ring to maintain a substantially constant resonant wavelength in the optical ring.

Abstract: Methods are described and related devices, compositions, and systems, in which a caged compound is administered to a biological environment, the caged compound being caged with a long wavelength absorber, the long wavelength being a wavelength greater than or equal to 750 nm; and irradiating the biological environment to excite the long wavelength absorber with light at a wavelength in a range from 900-1100 nm, thus decaging the compound.

Abstract: An integrated optical modulator includes, in part, a pair of waveguides and an inductor. The first waveguide is adapted to receive an incoming optical signal. The second waveguide includes a portion placed in proximity of the first waveguide so as to enable the incoming optical signal travelling in the first waveguide to couple to the second waveguide. The second waveguide comprises a p-n junction. The inductor has a first terminal coupled to the p-n junction and a second terminal coupled to a contact pad. The second waveguide has a circular shape. The inductor optionally has a spiral shape.

Abstract: A differential optical modulator includes, in part, a splitter splitting an incoming optical signal into first and second input signals, a first variable coupler generating a first differential output signal in response to the first input signal, and a second variable coupler generating a second differential output signal in response to the second input signal. The first variable coupler includes, in part, first and second couplers and a phase shifter disposed therebetween. The first coupler generates a pair of internal signals in response to the first input signal. The second coupler generates the first differential output signal. The second variable coupler includes, in part, third and fourth couplers and a phase shifter disposed therebetween. The third coupler generates a pair of internal signals in response to the second input signal. The fourth coupler generates the second differential output signal.

Abstract: Technologies are generally described for quadrature-based injection-locking of ring oscillators. In some examples, an external signal may be injected into a ring oscillator. Phase signals may be measured from within the ring oscillator and used to determine a mean quadrature error (MQE) that characterizes the difference in frequency between the external signal and the ring oscillator's natural frequency. A control signal may then be generated from the MQE and used to adjust the ring oscillator natural frequency to reduce the difference between the ring oscillator natural frequency and the external signal.

Abstract: Technologies are generally described for quadrature-based injection-locking offing oscillators. In some examples, an external signal may be injected into a ring oscillator. Phase signals may be measured from within the ring oscillator and used to determine a mean quadrature error (MQE) that characterizes the difference in frequency between the external signal and the ring oscillator's natural frequency. A control signal may then be generated from the MQE and used to adjust the ring oscillator natural frequency to reduce the difference between the ring oscillator natural frequency and the external signal.

Abstract: Technologies are generally described for implementing non-linear VCSEL equalization. In some examples, a rising edge tap parameter, a falling edge tap parameter, an equalization delay and a bias current may be used to equalize a data signal to be output from a VCSEL. A VCSEL model may be used to derive a VCSEL response to one or more isolated data pulses. The derived response may then be used to determine the rising and falling edge tap parameters and an equalization delay, based on a bias current value for the VCSEL and a data rate associated with the data signal. The data signal may then be adjusted based on the equalization delay and the rising and falling edge tap parameter and sent to the VCSEL for output. At the same time, the VCSEL may be biased with a bias current having the bias current value.

Abstract: Technologies are generally described for quadrature-based injection-locking of ring oscillators. In some examples, an external signal may be injected into a ring oscillator. Phase signals may be measured from within the ring oscillator and used to determine a mean quadrature error (MQE) that characterizes the difference in frequency between the external signal and the ring oscillator's natural frequency. A control signal may then be generated from the MQE and used to adjust the ring oscillator natural frequency to reduce the difference between the ring oscillator natural frequency and the external signal.

Abstract: A receiver architecture is disclosed which employs an RC double-sampling front-end and dynamic offset modulation technique. A low-voltage double-sampling technique provides high power efficiency by avoiding linear high-gain elements conventionally employed in typical transimpedance-amplifier (TIA) receivers. In addition, a demultiplexed output of the receiver helps save power in the subsequent digital blocks. Various applications are described including optical receivers, electrical on-chip interconnects, as well as pulse amplitude modulation. The receiver can be implemented in CMOS and is scalable and portable to other technologies.