The invention concerns a method for nonperturbative detection of one or more magnetic inhomogeneities resulting from nano-defects in a single longitudinal anisotropic magnetic sample structure having a nanometric cross-sectional dimension. A solid-state lattice with a single spin defect is used for magnetometry assessment of the anisotropic magnetic sample structure to determine quantitative information concerning minor defects and inconsistencies in the sample structure.

Provided herein are Mycobacterium smegmatis porin nanopores, systems that comprise these nanopores, and methods of using and making these nanopores. Such nanopores may be wild-type MspA porins, mutant MspA porins, wild-type MspA paralog porins, wild-type MspA homolog porins, mutant MspA paralog porins, mutant MspA homolog porins, or single-chain Msp porins. Also provided are bacterial strains capable of inducible Msp porin expression.

A light-trapping geometry enhances the sensitivity of strain, temperature, and/or electromagnetic field measurements using nitrogen vacancies in bulk diamond, which have exterior dimensions on the order of millimeters. In an example light-trapping geometry, a laser beam enters the bulk diamond, which may be at room temperature, through a facet or notch. The beam propagates along a path inside the bulk diamond that includes many total internal reflections off the diamond's surfaces. The NVs inside the bulk diamonds absorb the beam as it propagates. Photodetectors measure the transmitted beam or fluorescence emitted by the NVs. The resulting transmission or emission spectrum represents the NVs' quantum mechanical states, which in turn vary with temperature, magnetic field strength, electric field strength, strain/pressure, etc.

Systems and methods for pointwise encoding time reduction with radial acquisition (PETRA) magnetic resonance imaging (MRI) using a gradient modulation scheme to enable higher readout bandwidth while keeping the missing samples of the central region of k-space small are provided. This acquisition scheme allows independent selection of the excitation and readout bandwidths, which allows a higher readout bandwidth while keeping the required number of missing central k-space samples low. This flexibility in selecting the excitation and readout bandwidth settings can mitigate the peak radio frequency power and specific absorption rate limitations on flip angle in traditional PETRA imaging schemes.

A magnetic measurement device has a magnetic sensor including a glass cell having alkali metal gas encapsulated therein that is configured to detect a magnetic field using a magneto-optical characteristic of spin-polarized alkali metal. A laser light source is configured to generate pump light introduced into the magnetic sensor and a coil provided in the same magnetically shielded space as the magnetic sensor is configured to apply a static magnetic field and a RF magnetic field to the magnetic sensor. A signal processor is configured to perform lock-in detection of a light detection signal transmitted through the glass cell of the magnetic sensor, control an intensity of the static magnetic field and a frequency of the RF magnetic field generated by the coil according to a lock-in detection output, and obtain a measurement signal reflecting a magnetic field intensity of an object to be measured in the magnetically shielded space.

The invention provides methods of detecting an analyte by multi-stage mass spectrometry with improved S/N ratio. An analyte is labeled with a positively-charged mass tag to form a precursor ion that leads by anchimeric assistance to a greatly enhanced, analyte-characteristic first product ion that can, in turn, lead to a greatly enhanced, analyte-characteristic second product ion in a mass spectrometer. Either a three stage mass spectrometer (true MS3) or a two-stage mass spectrometer (MS2) operated in a pseudo MS3 mode can be used. The precursor ion is split via an anchimeric-assisted reaction to form a first product ion, which in turn can be fragmented to form the second product ion. The methods offer extreme ultrasensitivity, at the low amol level. The invention also provides anchimeric mass tags for use in the methods. A wide variety of previously undetectable analytes of biological or environmental origin can be detected and quantified.

Disclosed herein are methods of preparing a composition comprising crystalline biomolecules, for example, crystalline antibodies. In exemplary embodiments, the method comprises forming a fluidized bed of crystalline biomolecules using, for example, a counter-flow centrifuge to exchange buffer and/or to concentrate the crystalline biomolecules in a solution. Also provided are methods of detecting crystalline biomolecules and/or amorphous biomolecules in a sample.

A sensor system is based on diamonds with a high density of NV centers. The description includes a) methods for producing the necessary diamonds of high NV center density, b) characteristics of such diamonds, c) sensing elements for utilizing the fluorescence radiation of such diamonds, d) sensing elements for utilizing the photocurrent of such diamonds, e) systems for evaluating these quantities, f) reduced noise systems for evaluating these systems, g) enclosures for using such systems in automatic placement equipment, h) methods for testing these systems, and i) a musical instrument as an example of an ultimate application of all these devices and methods.

The present disclosure relates to a method for validating an existence of a urinary exosome including steps as follows. A urine sample is obtained from a subject. The urine sample is performing a serially centrifugation step to obtain a third precipitate. The third precipitate is resuspended with an extraction solvent to obtain a third mixture, and the third mixture is centrifuged to obtain a fourth supernatant. The fourth supernatant is analyzed by a mass spectrometry to detect whether there is a particular peptide therein.

An exhaust gas sensing system includes a channel for flow of exhaust gas, a first directional antenna, a second directional antenna, a first transmitter, a first receiver, and signal processing circuitry. The first directional antenna and the second directional antenna are disposed in the channel. The first transmitter is coupled to the first directional antenna. The first receiver is coupled to the second directional antenna. The signal processing circuitry is coupled to the first transmitter and the first receiver.