Abstract: Systems and methods for use in measuring sympathetic nervous system activity or blood vessel autoregulation corrected for sympathetic activity. The choroid plexus in the human eye is imaged and, using the resulting image, the vascular perfusion density (VPD) in the choroid is measured. VPD provides a measurement that is directly related to sympathetic nervous system activity. The effect of stimuli on sympathetic nervous system activity can be measured by comparing pre-stimuli VPD measurements with post-stimuli measurements. Quantifying VPD can be performed by determining pixel density within specific areas of the choroid plexus image. Altered sympathetic nervous system activity can be detected in a subject by comparing that subject's VPD measurements to baseline VPD measurements from healthy individuals. Blood vessel autoregulation can be measured by imaging changes in other blood vessels in the eye and correcting with choroid VPD measurements of sympathetic activity.

Abstract: An ophthalmic imaging system has a specialized graphical user interface GUI to convey information for manually adjusting control inputs to bring an eye into alignment with the device. The GUI provides additional information such as laterality, visual alignment overlay aids, and live video feeds. The system further applies automatic gain control to fundus images, synchronizes itself with other ophthalmic systems on a computer network, and provides an optimized image load and display system.

Abstract: A rebound tonometer is improved by providing a tilt signal from a tilt sensor of the rebound tonometer to a signal processor of the rebound tonometer, and configuring the signal processor to apply a tilt correction factor to a basic IOP measurement value calculated by the signal processor to provide a final IOP measurement value, wherein the tilt correction factor depends on a tilt direction and a degree of tilt indicated by the tilt signal. The final reported IOP measurement value takes into account gravitational effects on the probe due to tilt. As a result, measurements made at relatively small tilt angles are now usable, thereby improving efficiency. A corresponding rebound tonometry measurement method, and a method of calibrating a rebound tonometer for tilt correction, are also disclosed.

Abstract: Various examples are directed to systems and methods for measuring a parameter related to patient health. An analyte sensor system may detect that the analyte sensor system has been applied to a host and may store analyte data describing the host. The analyte sensor system may determine that sensor use at the analyte sensor system has terminated and upload stored analyte data to an upload computing device.

Abstract: A non-contact vital-sign monitoring system having a radar disposed in vicinity of a monitored subject includes a data buffer storing output signals of the radar sampled in sequence during a predetermined period; a status classifier determining status of the monitored subject; and a vital-sign detector determining a vital sign of the monitored subject according to the output signals of stationary status.

Abstract: Embodiments described herein relate to an implantable device that include an inductor coil, a storage capacitor, active circuitry, and a sensor, but doesn't include an electrochemical cell, and methods for use therewith. During first periods of time, the storage capacitor accumulates and stores energy received via the inductor coil from a non-implanted device. During second periods of time, interleaved with the first periods of time, and during which energy is not received from the non-implanted device, the active circuitry of the implantable device is powered by the energy stored on the storage capacitor and is used to perform at least one of a plurality of predetermined operations of the implantable device, including, e.g., obtaining a sensor measurement from the sensor of the implantable device, transmitting a communication signal including a sensor measurement to the non-implanted device, and/or receiving a communication signal from the non-implanted device.

Abstract: A skull-mounted drug and pressure sensor (SOS), a smart pump (ISP) electrically coupled to the SOS and a drug delivery and communications catheter communicating the SOS with the ISP are combined for a first embodiment. A skull-mounted (SOS), a metronomic biofeedback pump (MBP) electrically coupled to the SOS and a drug delivery and communications catheter having a sending and receiving optical fiber communicating the SOS with the MBP are combined for a second embodiment. A third embodiment combines a (SOS), an implantable power and communication unit (PCU) electrically coupled to the SOS, and a drug delivery and communications catheter for communicating the SOS with the PCU and for communicating the exterior source of the drug to the SOS. A fourth embodiment combines a ventricular catheter with a CSF accessible chamber and drug delivery port; and an implantable stand-alone skull-mounted drug and pressure sensor (SPS).

Abstract: The invention relates to a Handheld Biophotonic Medical (HBM) device for multimodal and multispectral imaging of a tissue. The HBM device comprises a hardware switch that provides trigger pulses to control unit of the HBM device, which controls an illumination unit to illuminate the tissue. Further, HBM device controls a miniature monochrome imaging device to stream live video image of tissue fluorescence and to capture images of tissue fluorescence and diffusely reflected light in real-time based on the light of specific wavelengths received from a collection optics unit upon illumination of the tissue. The control unit transmits the captured images to a computing device that determines grade of cancer and inflammation by analysing the captured images. The HBM device is light weighted, portable, can be inserted into body parts such as oral cavity, cervix and can also be mounted on endoscopes to examine internal organs of body.

Abstract: The present disclosure disclose a near-infrared spectroscopy tomography reconstruction method based on neural network which belongs to the field of medical image processing. In the Boltzmann radiation transmission equation, transmission process of light is regarded as absorption and scattering process of photons in medium, and interaction between light and tissue is determined by absorption coefficient, scattering coefficient and phase function of the response scattering distribution. In the transmission, only the particle property of light is taken into account, not the fluctuation of light. Therefore, polarization and interference phenomena related to the fluctuation of light are not considered, and only the energy transmission of light is tracked. The reconstruction method based on BP neural network is used to reconstruct the distribution of optical absorption coefficient, reconstruction results of absorption coefficient distribution can be obtained by calculation.

Abstract: A diagnostic toothbrush comprising, in combination, a toothbrush body, a standard brush head containing toothbrush bristles for brushing teeth, a diagnostic brush head containing a transducer that can detect a dental pathology, and a camera brush head that can produce video images of dental and oral structures. The standard brush head, the diagnostic brush head and the camera brush head can be interchangeably mounted on the toothbrush body. Data from the diagnostic brush head is transferred to the toothbrush body when the diagnostic brush head is mounted on the toothbrush body, data from the camera brush head is transferred to the toothbrush body when the camera brush head is mounted on the toothbrush body, and the data from the diagnostic and camera brush heads is transmitted from the toothbrush body to a computing device.

Abstract: A method and system for estimating fractional fat content of an object of interest. The method and system include a thermoacoustic imaging system comprising an adjustable radio frequency (RF) applicator configured to emit RF energy pulses into the region of interest and heat tissue therein and an acoustic receiver configured to receive bipolar acoustic signals generated in response to heating of tissue in the region of interest; and one or more processors. The one or more processors are able to process bipolar acoustic signals received by the acoustic receiver in response to RF energy pulses emitted into the region of interest using the RF applicator to determine a setting for the RF applicator that yields bipolar acoustic signals with at least one enhanced metric thereof, determine an impedance of the RF applicator used to yield acoustic bipolar signals with the enhanced at least one metric, and estimate fractional fat content of the object of interest using the determined impedance.

Abstract: The invention relates to a device (1) for endoscopic optoacoustic imaging comprising an imaging unit (2) configured to be at least partially inserted into an object (5), said imaging unit (2) comprising an irradiation unit (6) configured to irradiate a region of interest (7) inside the object (5) with electromagnetic radiation and a detection unit (8) comprising at least one ultrasound transducer configured to detect ultrasound waves generated in the region of interest (7) in response to irradiating the region of interest (7) with the electromagnetic radiation and to generate according detection signals, wherein the at least one ultrasound transducer exhibits a field of view (8b) being at least partially located in the irradiated region of interest (7).

Abstract: An apparatus for optical detection of ultrasound includes one or more optical resonators (OR—200), one or more optical passive-demodulation interferometers (OPDI—22), and one or more respective electro-optical readout circuits (EORC—24). The one or more optical resonators (OR) are configured to modulate respective carrier frequencies of optical signals indicative of US waves impinging thereon. The one or more OPDI are implemented in one or more photonic integrated circuits (PIC), wherein each OPDI is configured to demodulate the optical signal output by the respective OR, so as to generate a respective intensity-modulated optical signal. Each OPDI includes an interferometer (32) having imbalanced arms (323, 325) that are recombined using an optical hybrid (34). The one or more respective EORC are each configured to measure the intensity demodulated optical signal produced by the respective OPDI, and to output a respective electrical signal.

Abstract: The present disclosure provides a system for analyzing physiological signals. The system comprises a visual output module for rendering a visual output space according to a plurality of analyzed data sets generated by a analysis module, and displaying a visual output, wherein the visual output comprises a first axis representing frequency modulation (FM), a second axis representing amplitude modulation (AM), and a plurality of visual element defined by the first axis and the second axis, and each of the visual elements comprises an accumulated signal strength and the analyzed data sets.

Abstract: An implantable measurement device is disclosed which includes a first anchoring component which engages a first inner wall defining a first chamber of a heart, a first sensing element which performs physiologic measurements in the first chamber, and a second sensing element which performs physiologic measurements in the second chamber.

Abstract: A noninvasive physiological sensor can include a first body portion and a second body portion coupled to each other and configured to at least partially enclose a user's finger. The sensor can further include a first probe coupled to one or more emitters and a second probe coupled to a detector. The first probe can direct light emitted from the one or more emitters toward tissue of the user's finger and the second probe can direct light attenuated through the tissue to the detector. The first and second probes can be coupled to the first and second body portions such that when the first and second body portions are rotated with respect to one another, ends of the first and second probes can be moved in a direction towards one another to compress the tissue of the user's finger.

Abstract: Systems and methods for monitoring of physiological signals together with subject awareness information, including measuring and analyzing blood pressure and contextual blood pressure analysis of subjects. Systems and methods of non-invasive (optionally continuous or waveform) blood pressure measurement of subjects with sensor-derived data such as subject's activity, posture, location, place, time, etc.

Abstract: An identification device including a wave extraction unit, a time difference unit, and an information identification unit. The wave extraction unit extracts an ejection wave occurring in reply to heartbeat and a reflected wave occurring in reply to passage of blood outflowing from a heart through a bifurcation of blood vessels, from pulse wave information representing a pulse wave of an identification target. The time difference unit generates time-difference information representing a time difference between the extracted ejection wave and the extracted reflected wave.

Abstract: An apparatus and a method for estimating cardiovascular information. The apparatus for estimating cardiovascular information may include: a memory storing instructions; a processor configured to execute the instructions to: obtain a pulse wave signal of an object; determine an area under the pulse wave signal and above a reference point on the pulse wave signal; and estimate cardiovascular information of the object based on the determined area of the pulse wave signal.

Abstract: Methods, devices and machine readable programs are presented for measuring blood pressure using a device configured to guide a user regarding placement of an anatomical region of interest in relation to a sensor. The methods can includes measuring, by the sensor, a pressure applied to the sensor and measuring, by the sensor, blood volume oscillations in the anatomical region of interest while pressure is being applied to the sensor by the anatomical region of interest. The methods can further include estimating, by processing circuitry (e.g, computer processor(s), memory and the like) of the device, a blood pressure value for the user from the measured pressure and the measured blood volume oscillations.

Abstract: A noninvasive physiological sensor for measuring one or more physiological parameters of a medical patient can include a bump interposed between a light source and a photodetector. The bump can be placed in contact with body tissue of a patient and thereby reduce a thickness of the body tissue. As a result, an optical pathlength between the light source and the photodetector can be reduced. In addition, the sensor can include a heat sink that can direct heat away from the light source. Moreover, the sensor can include shielding in the optical path between the light source and the photodetector. The shielding can reduce noise received by the photodetector.

Abstract: A pulse wave measurement device (100) comprises an electrode unit (200) and a pulse wave measurement unit (1) including a pair of current applying electrodes and a pair of voltage measuring electrodes. The electrode unit (200) includes a substrate (210) with insulating properties, measurement electrodes (220), connection electrodes (230) electrically connected to the measurement electrodes (220) in a 1-to-1 manner, and an adhesive layer. The pulse wave measurement unit (1) includes a belt member (20) configured to wrap around a living body and cover the electrode unit (200) attached to a body surface.

Abstract: The invention relates to a device for determining a parameter for the diagnostics of hydrocephalus and other disorders of intracranial pressure, wherein information about the volume elasticity is obtained from a pressure signal or another characteristic signal which contains information about the pressure or the volume composition in the skull. The characteristic parameter determined according to the invention is the ratio of the amplitude of a modulating wave in the processed characteristic signal to the amplitude of the modulated wave in the course of the pulse amplitude of the modulated wave of the processed characteristic signal.

Abstract: Devices, systems, and methods directed to detecting positions of a catheter relative to cardiac regions of a patient are disclosed herein. In some implementations, an ablation system can include a cardiac catheter and a catheter interface unit in communication with one or more electrodes and/or sensors on the cardiac catheter. The devices, systems, and methods of the present disclosure can identify regions of the heart based on one or more signals from the respective one or more electrodes and/or sensors. In these and other implementations, the devices, system, and methods can display visual indicia based on an identified cardiac region.

Abstract: System and method for providing patient-specific models to distinguish between epochs of electrocardiograms (ECGs) located far away from atrial fibrillation rhythms and those located just prior to the onset of those episodes, to provide for the prediction of the onset of an occurrence of atrial fibrillation (AF) in the patient.

Abstract: The present invention provides a magnetic monitoring system for imaging, monitoring, scanning or mapping for brain or heart activity of subjects including children and adults, the system comprising of a magnetoencephalographic or magnetocardiographic system incorporating SQUID sensors for measuring brain activity or heart activity, the system including a plurality of Dewar helmets of variable sizes and shapes; and a plurality of monitoring interfaces; wherein the sensor system helmet is moveable by horizontal Dewar rotation. The sensor system includes configurations where the size and shape of helmets in the system may be different to accommodate different sized subjects for monitoring simultaneously.

Abstract: The present invention relates to a device for detecting a state of true perception loss of a human, the device including processing means operable to detect from information on electrical signals sensed adjacent to the scalp of the human the activity of oscillations present in the electrical signals as a marker for the state of true perception loss of the human.

Abstract: A method includes receiving an electrocardiogram (ECG) measured at a given location over a portion of a heart. Based on the measured ECG, a rhythmic pattern is identified over a given time-interval. The rhythmic pattern corresponds to a relation between a present cardiac cycle length and a preceding cardiac cycle length. Based on the identified rhythmic pattern, a classification of the location as either showing regular pattern or showing arrhythmia is determined. The location is graphically encoded according to the classification. The graphically encoded location is overlaid on an anatomical map of the portion of a heart.

Abstract: A method includes receiving an anatomical map of at least a portion of a heart. Positions and respective electrocardiogram (ECG) signal amplitudes measured at the positions are received for at least a region of the anatomical map. The ECG signal amplitudes are interpolated to derive a surface representation of the ECG signal amplitudes over the region. The surface representation of the ECG signal amplitudes is presented overlaid on the anatomical map.

Abstract: Apparatus for assessing scarring of cardiac tissue, consisting of a probe and a processor. The probe has one or more electrodes, which are configured to contact the tissue at a plurality of positions and to sense respective voltages in the tissue at the positions. The processor receives the respective voltages, and computes a triangular mesh that is representative of a surface of the tissue and that consists of multiple triangles having vertices corresponding to the positions contacted by the one or more electrodes. The processor calculates respective scar areas within the triangles by comparing the respective voltages sensed at the positions corresponding to the vertices to a predefined range of the voltages that is associated with scarring, and computes a sum of the respective areas. The processor compares the sum to a total area of the triangles so as to assess a degree of the scarring of the tissue.

Abstract: Methods and related systems and devices for cardiac therapy use pseudo-electric vectors (PEVs) for characterizing and representing the electrical forces generated by a patient's heart in a three-dimensional (3D) manner. PEVs may be used to predict whether a patient will respond to pacing therapy prior to implant, during implant, or in the follow-up after implant. Various cardiac therapy systems and devices, such as an electrocardiogram (ECG) belt or vest, which may include a plurality of external electrodes, may be used to obtain electrical activity information to generate the PEVs. One or more spatio-temporal PEVs may be determined using one or more sensors at one or more points in time. Spatial representation data may be determined based on the PEVs.

Abstract: This document describes methods and materials for mapping and modulating repolarization. For example, this document relates to methods and devices for mapping and modulating repolarization to target atrial and ventricular arrhythmias to deliver electrical stimulation pacing, ablation and/or electroporation.

Abstract: A system and method for measuring the impedance of one or more of a plurality of leads in an electrocardiogram (ECG) are disclosed. These may include applying a plurality of leads to a patient's body, applying a plurality impedance pads to the patient's body, providing a burst pulse from the catheter electrode of the ECG, measuring impedance signals across ones of the plurality of impedance pads and the plurality of leads, and determining the impedance for one or more leads from the measure impedance signals. The plurality of impedance pads may define a first axis from the ride side of the patient's chest to the left side of the patient's chest, a second axis from the upper chest area of the patient to the lower abdomen area of the patient, and a third axis from the center of the patient's back to the center of the patient's chest.

Abstract: A system includes two or more pairs of electrodes and a processor. The electrodes are disposed over a distal end of a catheter for insertion into a heart of a patient. The electrodes in each pair are parallel with one another, and the pairs are not parallel with one another. The processor is configured to receive electrophysiological (EP) signals acquired by the pairs of electrodes, and, based on a timing of the received EP signals, calculate a local direction at which the received EP signals propagate in the heart.

Abstract: A catheter adapted for mapping and/or ablation in the atria has a basket-shaped electrode array with two or more location sensors with a deflectable expander. The catheter comprises a catheter body, a basket electrode assembly at a distal end of the catheter body, and a control handle at a proximal end of the catheter body. The basket electrode assembly has a plurality of electrode-carrying spines and an expander that is adapted for longitudinal movement relative to the catheter body for expanding and collapsing the assembly via a proximal end portion extending past the control handle that can be pushed or pulled by a user. The expander is also adapted for deflection in responsive to an actuator on the control handle that allows a user to control at least one puller wire extending through the catheter body and the expander.

Abstract: A method of generating a model for generating a synthetic electrocardiography (ECG) signal comprises: receiving subject-specific training data for machine learning, said training data comprising a photoplethysmography (PPG) signal acquired from the subject and an ECG signal acquired from the subject, wherein the ECG signal provides a ground truth of the subject for associating the ECG signal with the PPG signal; using associated pairs of a time-series of the PPG signal and a corresponding time-series of the ECG signal as input to a deep neural network, DNN; and determining, through the DNN, a subject-specific model relating the PPG signal of the subject to the ECG signal of the subject for converting the PPG signal to a synthetic ECG signal using the subject-specific model.

Abstract: A method for detecting long QT syndrome in a subject comprises obtaining data corresponding to an electrocardiogram (ECG) signal of the subject, identifying a set of features in the data based on selected inflection points of the ECG signal, using the set of features to categorize segments of the ECG signal, and using the categorized segments of the ECG signal and the inflection points to classify the ECG signal as normal or as long QT syndrome. Long QT syndrome is detected when the subject's ECG signal is classified as long QT syndrome. The method may include determining whether the long QT syndrome is Type 1 or Type 2.

Abstract: A medical device is configured to detect an atrial tachyarrhythmia episode. The device senses a cardiac signal, identifies R-waves in the cardiac signal attendant ventricular depolarizations and determines classification factors from the R-waves identified over a predetermined time period. The device classifies the predetermined time period as one of unclassified, atrial tachyarrhythmia and non-atrial tachyarrhythmia by comparing the determined classification factors to classification criteria. A classification criterion is adjusted from a first classification criterion to a second classification criterion after at least one time period being classified as atrial tachyarrhythmia. An atrial tachyarrhythmia episode is detected by the device in response to at least one subsequent time period being classified as atrial tachyarrhythmia based on the adjusted classification criterion.

Abstract: Electrodes for use in electroencephalographic recording, including consciousness and seizure monitoring applications, have novel features that speed, facilitate or enforce proper placement of the electrodes, including aligning tabs and arrowed aligning juts, color coding, and an insulating bridge between reference and ground electrodes which ensures a safe application distance between the conductive regions of the two electrodes in the event of cardiac defibrillation or to prevent shorting between the adjacent electrodes by preventing the conductive path to be shared. A method of using a set of four such electrodes is also disclosed.

Abstract: An electrode support includes a first reference electrode and a second electrode, the electrodes being electrically insulated from each other and able to measure two electric potentials at the surface of a haired animal body, the electrode support further including an electronic module including at least one memory, a calculator and a first electric interface to receive electric signals acquired from each electrode for recording a cardiac activity of the haired animal, the electrodes each including a one-piece structure formed of a polymer material in which conductive elements are distributed, the structure including a base and a plurality of projections able to go through a coat.

Abstract: A method for measuring spasticity is provided and includes: obtaining sensing signals corresponding to a limb movement through at least one sensor during a period of time; transforming the sensing signals into a two-dimensional image; and inputting the two-dimensional image into a convolutional neural network to output a spasticity determination result.

Abstract: A technique for determining skin sodium content using bioimpedance spectroscopy includes applying a current at a predetermined frequency to skin of a subject, measuring a voltage across the skin of the subject produced by the current, determining a resistance across the skin of the subject at the predetermined frequency using the measured voltage, and determining skin sodium content using the measured voltage.

Abstract: A flexible catheter includes an elongated body, and a sensor. The elongated body has proximal and distal end portions and defines a working channel therethrough. The sensor is disposed in the distal end portion of the elongated body and is adapted for detecting the position of a distal end of the elongated body within the anatomy of a patient. The sensor is formed from a wire that forms a first layer of wraps about the distal end portion of the elongated body and that includes first and second leads that form a twisted pair proximal to the first layer of wraps. The twisted pair of the first and second leads extends to the proximal end portion of the elongated body.

Abstract: Systems and methods for tracking a probe during a procedure. In one embodiment, the method includes monitoring a position of the probe in an imaging region during the procedure using microwave inverse scattering and contrast source inversion. The method also includes solving for a contrast source in the imaging region using compressive sensing and group sparsity. The contrast source exists at a surface of the probe or within the probe. The method further includes imaging the contrast source and the probe by solving a linear inverse scattering problem with a group sparsity constraint. The method also includes determining a location of the probe in the imaging region during the procedure based on the imaging of the contrast source and the probe. The method further includes displaying an image of the location of the probe relative to an anatomy feature in the imaging region during the procedure.

Abstract: A location tracking system maps anatomical structures in a first coordinate system, in a fixed position within a medical imaging system, which captures 3D images in a second coordinate system. The 3D images are converted to and stored in a standardized format in a third coordinate system in accordance with a first coordinate transformation. A first 3D image captured by the imaging system is registered with the first coordinate system so as to produce a second coordinate transformation. The first and second coordinate transformations are combined so as to derive a third coordinate transformation between the first and third coordinate systems. A second 3D image of a body of a subject, captured by the imaging system, is processed in order to extract image features in the third coordinate system. The extracted image features are joined with location data captured by the location tracking system by applying the third coordinate transformation.

Abstract: Guidewires and methods useable in conjunction with image guidance systems to facilitate performance of diagnostic or therapeutic tasks at locations within the bodies of human or animal subjects.

Abstract: Methods and systems for position determination of an intrabody probe, targets of an intrabody probe, and or actions to be performed using an intrabody probe are described. In some embodiments, an anatomy being navigated and/or mapped is described by a rule-based schema relating different anatomically identified structures to one another according to their ability to help identify and/or locate one another. Additionally, in some embodiments, data recorded from the intrabody probe is processed according to schema rules in order to provide anatomical identification of the anatomical region which the intrabody probe is sampling, optionally without performing detailed mapping, and/or prior to the availability of detailed mapping of anatomical geometry.

Abstract: Embodiments described herein are directed to non-invasive detection of peripheral arterial disease. For example, a measuring apparatus is used to measure a patient's calf circumference. The measuring apparatus has text feature(s) or indicator(s) printed thereupon that indicate the likelihood that the patient has peripheral arterial disease based on the measured calf circumference. The assessment may be further refined by using a software application that assesses the likelihood of the patient having peripheral arterial disease using at least the calf circumference measurement, along with other information/data. Based on the assessment, a healthcare practitioner may prescribe a walking program for the patient to follow. A software application may track compliance of the walking program and provide escalating reminders to the patient if the patient continues to fail to comply with the prescribed walking program.

Abstract: This invention is related to motion pattern monitoring apparatus, comprising: measurement module and monitoring unit; with the said measurement modules being placed in the part of the body of the patient to be monitored; with the monitoring unit being carried by the patient; with the monitoring unit connected by wireless communication to the said measurement modules; with the said measurement modules acquiring the motion signals from the patient and transmitting the motion signals to the monitoring unit, with the monitoring unit analyzing the motion signals to detect the peaks of the signals and to measure the peak amplitudes and peak intervals between two consecutive peaks, and accordingly to identify the motion pattern based on the said peak information. The invention uses the peak amplitudes and peak intervals to detect the motion patterns.

Abstract: A method of monitoring respiration with an acoustic measurement device, the acoustic measurement device having a sound transducer, the sound transducer configured to measure sound associated with airflow through a mammalian trachea, the method includes correlating the measured sound into a measurement of tidal volume and generating at least one from the group consisting of an alert and an alarm if the measured tidal volume falls outside of a predetermined range.