A Proposal for a Wirelessly Powered, Implantable Pressure Sensor and Neural Stimulator for the Control of Urinary Incontinence

47 to 53 percent of women over the age of 20 suffer from urinary incontinence, often caused by childbirth-related damage to the pelvic nerve. This uncertainty of when bladder voiding will occur causes social anxiety and can compromise quality of life. This study explores one method to restore the ability to sense the need to urinate and prevent unwanted voiding. We propose a device to measure pressure due to bladder content as the difference between pressure in the bladder and pressure in the abdominal cavity. Integrated circuits, biocompatible packaging, and wireless radiofrequency powering allow for a fully implantable device to process the pressure data, stimulate the pelvic nerve, and stop stimulation on command. The device recognizes pressure spikes similar to those seen in the bladder prior to urinating and stimulates the pelvic nerve in acute surgeries. We hope to chronically implant the device soon to monitor long-term performance and effects of the device in vivo

Low Power, Low Noise Circuit for Biological Signal Recording

Implantable devices are ideal for recording biological signals in animal models as they have minimal effect on the animal’s normal behavior during observation. The creation of the circuitry for an implantable device has several restrictions including size, power consumption, and noise reduction. These factors compete against each other, making it necessary to carefully optimize circuit components for a given application. This study evaluates the design of a four-channel analog front end circuit board to record cardiac, neural, and respiratory biological signals. Through a critical analysis of component specifications for the circuit’s components and an evaluation of the circuits’ power and noise performance, the ideal analog front end for the implantable biological recording device was designed. The combination using components AD8235 and OPA2348 decreased noise, power consumption, and size by 43%, 58%, and 57% respectively without significantly impacting other metrics. This combination was chosen to best improve the performance of the implantable device

Plataforma de anticuerpos antineoplásicos

Trabajo final de posgrado (Especialización en Gestión de la Innovación y Vinculación Tecnológica) -- Universidad Nacional de Córdoba. Facultad de Ciencias Económicas; Argentina, 2018.El cáncer es una de las principales causas de muerte de nuestra población por lo cual la sociedad reclama soluciones terapéuticas para los pacientes que padecen esta enfermedad. En los últimos años aparecieron en el mercado farmacéutico estrategias terapéuticas de inmunización pasiva con anticuerpos antineoplásicos que lograron valores de comercialización de 20.000.000 de dólares anuales en nuestro país, y en donde se trataron solo un pequeño porcentaje de los pacientes con tumores epiteliales. Solo en Argentina el mercado tiene la potencialidad de crecer 20 veces en los próximos 10 años. Si esto se extrapola a Sudamérica podría crecer más de 100 veces. El presente proyecto propone generar múltiples anticuerpos con aplicaciones terapéuticas orientados a la producción de medicamentos para inmunoterapia antineoplásica, con el propósito de poder disponer de una estrategia terapéutica personalizada para el tratamiento de tumores epiteliales. En este proyecto se propone purificar de plasma humano normal anticuerpos naturales anti-antígenos asociados a tumores (como anticuerpos anti-antígenos Tn, sialil-Tn y T), que todos los individuos normales poseemos, los que se utilizarán como inmunoterapia pasiva a pacientes con tumores epiteliales. Los antecedentes técnicos del proyecto se encuentran en una etapa de Laboratorio, y estos muestran que las dos poblaciones de anticuerpos obtenidas reconocen significativamente a tejidos humanos de carcinomas de riñón, mamas y colon, lo que genera altas expectativas sobre su potencial terapéutico. Es importante destacar que las especificidades de reconocimiento antigénico de estos anticuerpos son originales (esta propuesta no es generar biosimilares), por lo cual se resguardarán los derechos de propiedad intelectual mediante patentes. Para poder avanzar a la siguiente etapa de desarrollo del presente proyecto se realizó un análisis de diferentes fuentes de financiamiento, de lo que se concluye que la solicitud de un PICT Start Up es la opción de subsidio más recomendable para este proyecto. También se analiza un Flujo de Fondos y la Gestión del Proyecto.Fil: Irazoqui, Fernando J. Universidad Nacional de Córdoba. Facultad de Ciencias Económicas; Argentina

Detecting time-fragmented cache attacks against AES using Performance Monitoring Counters

Cache timing attacks use shared caches in multi-core processors as side channels to extract information from victim processes. These attacks are particularly dangerous in cloud infrastructures, in which the deployed countermeasures cause collateral effects in terms of performance loss and increase in energy consumption. We propose to monitor the victim process using an independent monitoring (detector) process, that continuously measures selected Performance Monitoring Counters (PMC) to detect the presence of an attack. Ad-hoc countermeasures can be applied only when such a risky situation arises. In our case, the victim process is the AES encryption algorithm and the attack is performed by means of random encryption requests. We demonstrate that PMCs are a feasible tool to detect the attack and that sampling PMCs at high frequencies is worse than sampling at lower frequencies in terms of detection capabilities, particularly when the attack is fragmented in time to try to be hidden from detection

A Non-invasive Method of Measuring Respiration while Providing Wireless Power for Rodents with Implantable Devices

Respiratory measurements can be used as diagnostic and research tools. Spirometry is the gold standard for gaining these measurements, but is difficult to use in rodents as it requires an invasive procedure. Total Body Plethysmograpy (TBP) is a non-invasive way to measure respiration rates that does not cause stress to the rodent. In this system, the subject is encased in a solid, constant volume chamber with measurements determining the subject’s respiration. When using TBP in medical or research settings, challenges occur in powering devices within the TBP chamber as wires and other recording equipment compromise the airtightness of the chamber. Therefore, it is imperative to create a TBP chamber that provides wireless power for these purposes. To do so, subjects were placed in a cubic or cylindrical airtight chamber with one inflow and exhaust nozzle to control chamber pressure and provide a steady stream of fresh oxygen. Pressure readings from the inside of the chamber were taken at a rate of four samples per second. Tests were run from two minutes to three hours to encompass rodent activity. Tests were inconclusive for measuring respiration with the specific sensors used, and further research and testing is needed to perfect this method. Once the method is proven to work with the pressure sensors, it will be able to be paired with the MRC chasm and therefore implemented in other studies

CacheZoom: How SGX Amplifies The Power of Cache Attacks

In modern computing environments, hardware resources are commonly shared, and parallel computation is widely used. Parallel tasks can cause privacy and security problems if proper isolation is not enforced. Intel proposed SGX to create a trusted execution environment within the processor. SGX relies on the hardware, and claims runtime protection even if the OS and other software components are malicious. However, SGX disregards side-channel attacks. We introduce a powerful cache side-channel attack that provides system adversaries a high resolution channel. Our attack tool named CacheZoom is able to virtually track all memory accesses of SGX enclaves with high spatial and temporal precision. As proof of concept, we demonstrate AES key recovery attacks on commonly used implementations including those that were believed to be resistant in previous scenarios. Our results show that SGX cannot protect critical data sensitive computations, and efficient AES key recovery is possible in a practical environment. In contrast to previous works which require hundreds of measurements, this is the first cache side-channel attack on a real system that can recover AES keys with a minimal number of measurements. We can successfully recover AES keys from T-Table based implementations with as few as ten measurements.Comment: Accepted at Conference on Cryptographic Hardware and Embedded Systems (CHES '17

A Flexible Platform for Biofeedback-driven Control and Personalization of Electrical Nerve Stimulation Therapy

Electrical vagus nerve stimulation is a treatment alternative for many epileptic and depressed patients whose symptoms are not well managed with pharmaceutical therapy. However, the fixed stimulus, open loop dosing mechanism limits its efficacy and precludes major advances in the quality of therapy. A real-time, responsive form of vagus nerve stimulation is needed to control nerve activation according to therapeutic need. This personalized approach to therapy will improve efficacy and reduce the number and severity of side effects. We present autonomous neural control, a responsive, biofeedback-driven approach that uses the degree of measured nerve activation to control stimulus delivery. We demonstrate autonomous neural control in rats, showing that it rapidly learns how to most efficiently activate any desired proportion of vagal A, B, and/or C fibers over time. This system will maximize efficacy by minimizing patient response variability and by minimizing therapeutic failures resulting from longitudinal decreases in nerve activation with increasing durations of treatment. The value of autonomous neural control equally applies to other applications of electrical nerve stimulation

Radiational tides: their double-counting in storm surge forecasts and contribution to the Highest Astronomical Tide

Tide predictions based on tide-gauge observations are not just the astronomical tides; they also contain radiational tides – periodic sea-level changes due to atmospheric conditions and solar forcing. This poses a problem of double-counting for operational forecasts of total water level during storm surges. In some surge forecasting, a regional model is run in two modes: tide only, with astronomic forcing alone; and tide and surge, forced additionally by surface winds and pressure. The surge residual is defined to be the difference between these configurations and is added to the local harmonic predictions from gauges. Here we use the Global Tide and Surge Model (GTSM) based on Delft-FM to investigate this in the UK and elsewhere, quantifying the weather-related tides that may be double-counted in operational forecasts. We show that the global S2 atmospheric tide is captured by the tide-and-surge model and observe changes in other major constituents, including M2. The Lowest and Highest Astronomical Tide levels, used in navigation datums and design heights, are derived from tide predictions based on observations. We use our findings on radiational tides to quantify the extent to which these levels may contain weather-related components

The Rho GDI Rdi1 regulates Rho GTPases by distinct mechanisms

© 2008 by The American Society for Cell Biology. Under the License and Publishing Agreement, authors grant to the general public, effective two months after publication of (i.e.,. the appearance of) the edited manuscript in an online issue of MBoC, the nonexclusive right to copy, distribute, or display the manuscript subject to the terms of the Creative Commons–Noncommercial–Share Alike 3.0 Unported license (http://creativecommons.org/licenses/by-nc-sa/3.0).The small guanosine triphosphate (GTP)-binding proteins of the Rho family are implicated in various cell functions, including establishment and maintenance of cell polarity. Activity of Rho guanosine triphosphatases (GTPases) is not only regulated by guanine nucleotide exchange factors and GTPase-activating proteins but also by guanine nucleotide dissociation inhibitors (GDIs). These proteins have the ability to extract Rho proteins from membranes and keep them in an inactive cytosolic complex. Here, we show that Rdi1, the sole Rho GDI of the yeast Saccharomyces cerevisiae, contributes to pseudohyphal growth and mitotic exit. Rdi1 interacts only with Cdc42, Rho1, and Rho4, and it regulates these Rho GTPases by distinct mechanisms. Binding between Rdi1 and Cdc42 as well as Rho1 is modulated by the Cdc42 effector and p21-activated kinase Cla4. After membrane extraction mediated by Rdi1, Rho4 is degraded by a novel mechanism, which includes the glycogen synthase kinase 3β homologue Ygk3, vacuolar proteases, and the proteasome. Together, these results indicate that Rdi1 uses distinct modes of regulation for different Rho GTPases.Deutsche Forschungsgemeinschaf

Suppression of Urinary Voiding by Conditional High Frequency Stimulation of the Pelvic Nerve in Conscious Rats:Pelvic nerve stimulation suppresses urinary voiding

Female Wistar rats were instrumented to record bladder pressure and to stimulate the left pelvic nerve. Repeated voids were induced by continuous infusion of saline into the bladder (11.2 ml/h) via a T-piece in the line to the bladder catheter. In each animal tested (n = 6) high frequency pelvic nerve stimulation (1–3 kHz, 1–2 mA sinusoidal waveform for 60 s) applied within 2 s of the onset of a sharp rise in bladder pressure signaling an imminent void was able to inhibit micturition. Voiding was modulated in three ways: (1) Suppression of voiding (four rats, n = 13 trials). No fluid output or a very small volume of fluid expelled (<15% of the volume expected based on the mean of the previous 2 or 3 voids). Voiding suppressed for the entirety of the stimulation period (60 s) and resumed within 37 s of stopping stimulation. (2) Void deferred (four rats, n = 6 trials). The imminent void was suppressed (no fluid expelled) but a void occurred later in the stimulation period (12–44 s, mean 24.5 ± 5.2 s after the onset of the stimulation). (3) Reduction in voided volume (five rats, n = 20 trials). Voiding took place but the volume of fluid voided was 15–80% (range 21.8–77.8%, mean 45.3 ± 3.6%) of the volume expected from the mean of the preceding two or three voids. Spontaneous voiding resumed within 5 min of stopping stimulation. Stimulation during the filling phase in between voids had no effect. The experiments demonstrate that conditional high frequency stimulation of the pelvic nerve started at the onset of an imminent void can inhibit voiding. The effect was rapidly reversible and was not accompanied by any adverse behavioral side effects