Syringe Pump

Our team was asked to design a syringe pump that would deliver fluid at a controlled flow rate to cells in a microfluidic device. The design process of our syringe pump proved to be a very dynamic one. The beginning research of both microfluidic devices and existing syringe pumps helped our team get an idea of ways we could implement existing aspects that work into our design. There were many existing devices that resembled the one that we were asked to make closely; however, due to our resources as students, we had to be a bit more creative in figuring out how to afford and assemble each component to the best of our abilities. Developing customer requirements was a huge step in the process of understanding what exactly you as our customer wanted to see delivered in our syringe pump. The main requirements of our pump were that it was able to deliver accurate shear stress values so that they could mimic those found in true physiology, that it was able to deliver an accurate flow rate to the device, that it was easily usable, and that it was compact to both fit in a desired location and have ease of mobility when needed to be moved to or from that location. Next, it was our job as the engineers to turn those requirements into quantitative engineering specifications that our device needed to meet via testing of the device once the prototype was finished. Once we determined what numbers needed to be hit to quantify the requirements set by you, we were able to create a network diagram of tasks in order to organize the design, manufacturing, and testing processes that we had ahead. Our design process then became a series of brainstorming via tools like a conjoint analysis, morphology, and Pugh matrices. We did these exercises in order to compile a multitude of ideas for each component of the pump to determine which combination of these ideas would produce the optimal pump that is attractive to the user and does the best job at meeting the customer specifications. We determined the main functions of our pump were inputting flow rate parameters on the interface, having a power source for the pushing mechanism, the physical pushing mechanism, and lastly the mechanism through which the fluid would be delivered into the tube. Ultimately, through the many exercises as well as iterations due to a multitude of realizations down the road, we settled upon using a stepper motor linear actuator for the pushing mechanism and a screen with buttons for the input from the user, powered by a 24 V DC Power Supply and connected by a needle attachment to the syringe. Next came acquiring the materials and aspects of the pump that were to be purchased from a manufacturer as well as designing the aspects that we were going to manufacture ourselves. The primary component of our design that we purchased was the FUYU stepper motor linear actuator, to which we programmed electrically and designed adapters to fit onto. Our electrical programming revolved around the Arduino UNO and the Sketch coding software. The chassis was our last component to design, and its main purpose was to keep the user safe from any potential harm from the pump and protect the pump from any water or other wear. When we had performed the Hazard Safety Assessment, we determined a lot of the risk involved the user having their hands in the pinch points as well as having the device fall on the user, both of which were mitigated by having a chassis that covered the pinch point and made the device more compact and mobile. Once we had those components designed, we determined how we would both manufacture and assemble the final prototype. These plans were surely dynamic as we changed materials and found new ways to better manufacture each piece. Critical changes included changing the chassis material from acrylic to polycarbonate, and thus changing the manufacturing process from laser jetting to water jetting to using a variety of saws to cut the pieces. Another critical change came after having manufactured the pusher block adapter, as we were sent back to the design process when the adapter did not perform the way we wanted it to. Additionally, the electrical side of our design manufacturing had to be iterated multiple times as we determined what was feasible and still effective for inputting the parameters. Our design changed from a 4 x 4 keypad to two buttons, one increasing the flow rate value and one decreasing the value. Once the prototype had been built, it was time to verify that we had made a device that met the customer specifications. We created protocols for how we would test these specifications and executed each of the four, the most time-consuming ones being the flow rate and shear stress tests. Our testing plans for shear stress included both an analytical COMSOL simulation through the solid model of the microfluidic device as well as physical testing of the velocity of the particles moving via the LabSmith Micro Particle Image Velocimetry microscope. The physical testing was to verify that our analytical model accurately displayed what velocity and thus shear stresses the cells in our microfluidic devices would be experiencing. Next, we tested flow rate via running water through our pump at specified flow rates for a given period of time, measuring the mass acquired on a sensitive scale to back-calculate what flow rate was actually being delivered. Additionally, we used a gauge to measure the displacement of our pusher block over a specified time to first ensure that the correct speed was being programmed to the motor. In terms of surface area testing, we simply used a ruler to measure the dimensions of the bottom of our chassis to verify it would fit in the desired location in the lab. Lastly, our ease of use testing included simply numbering the steps in the operations manual. Ultimately, our data showed that we did in fact create a pump that received an input and delivered a controllable flow rate and shear stress to the cells in the microfluidic devices, all while being compact and easily usable. After inputting a flow rate of 28.8 ml/hr, we measured the delivered flow rate to be 25.5 ml/hr, which was within our target percent error range of 15%. For shear stress, when entering a flow rate of 75.8 uL/hr, our physical testing showed a particle velocity of 295.6 um/s and our COMSOL velocity showed one of 358.91 um/s, putting these within range of our 20% error goal. We measured the bottom surface area of our pump to be 431.85 cm^2, which was well within our specification of 695 cm^2. Lastly, we measured 5 steps to program our device, which was our target specification. There were surely limitations to our data, as when flow rate decreased to smaller and smaller values it was increasingly harder to acquire data, and then additionally extremely difficult to have that data be accurate. Thus, at the flow rate of 0.76 uL/hr, which is the flow rate at which the pump will typically be used at, both the shear stress and flow rate specifications were not met via our testing. There are a multitude of reasons why our data may have been skewed, and we have plans for future testing to discover where errors might be introduced in our pump. Overall, our team learned much about the design process and grew as engineers while designing this syringe pump

The international WAO/EAACI guideline for the management of hereditary angioedema—The 2021 revision and update

Hereditary angioedema (HAE) is a rare and disabling disease for which early diagnosis and effective therapy are critical. This revision and update of the global WAO/EAACI guideline on the diagnosis and management of HAE provides up-to-date guidance for the management of HAE. For this update and revision of the guideline, an international panel of experts reviewed the existing evidence, developed 28 recommendations, and established consensus by an online DELPHI process. The goal of these recommendations and guideline is to help physicians and their patients in making rational decisions in the management of HAE with deficient C1 inhibitor (type 1) and HAE with dysfunctional C1 inhibitor (type 2), by providing guidance on common and important clinical issues, such as: (1) How should HAE be diagnosed? (2) When should HAE patients receive prophylactic on top of on-demand treatment and what treatments should be used? (3) What are the goals of treatment? (4) Should HAE management be different for special HAE patient groups such as children or pregnant/breast-feeding women? and (5) How should HAE patients monitor their disease activity, impact, and control? It is also the intention of this guideline to help establish global standards for the management of HAE and to encourage and facilitate the use of recommended diagnostics and therapies for all patients

Measurement of the cosmic ray spectrum above 4×10184{\times}10^{18} eV using inclined events detected with the Pierre Auger Observatory

A measurement of the cosmic-ray spectrum for energies exceeding $4{\times}10^{18}$ eV is presented, which is based on the analysis of showers with zenith angles greater than $60^{\circ}$ detected with the Pierre Auger Observatory between 1 January 2004 and 31 December 2013. The measured spectrum confirms a flux suppression at the highest energies. Above $5.3{\times}10^{18}$ eV, the "ankle", the flux can be described by a power law $E^{-\gamma}$ with index $\gamma=2.70 \pm 0.02 \,\text{(stat)} \pm 0.1\,\text{(sys)}$ followed by a smooth suppression region. For the energy ($E_\text{s}$) at which the spectral flux has fallen to one-half of its extrapolated value in the absence of suppression, we find $E_\text{s}=(5.12\pm0.25\,\text{(stat)}^{+1.0}_{-1.2}\,\text{(sys)}){\times}10^{19}$ eV.Comment: Replaced with published version. Added journal reference and DO

Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger Observatory

The Auger Engineering Radio Array (AERA) is part of the Pierre Auger Observatory and is used to detect the radio emission of cosmic-ray air showers. These observations are compared to the data of the surface detector stations of the Observatory, which provide well-calibrated information on the cosmic-ray energies and arrival directions. The response of the radio stations in the 30 to 80 MHz regime has been thoroughly calibrated to enable the reconstruction of the incoming electric field. For the latter, the energy deposit per area is determined from the radio pulses at each observer position and is interpolated using a two-dimensional function that takes into account signal asymmetries due to interference between the geomagnetic and charge-excess emission components. The spatial integral over the signal distribution gives a direct measurement of the energy transferred from the primary cosmic ray into radio emission in the AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air shower arriving perpendicularly to the geomagnetic field. This radiation energy -- corrected for geometrical effects -- is used as a cosmic-ray energy estimator. Performing an absolute energy calibration against the surface-detector information, we observe that this radio-energy estimator scales quadratically with the cosmic-ray energy as expected for coherent emission. We find an energy resolution of the radio reconstruction of 22% for the data set and 17% for a high-quality subset containing only events with at least five radio stations with signal.Comment: Replaced with published version. Added journal reference and DO

Measurement of the Radiation Energy in the Radio Signal of Extensive Air Showers as a Universal Estimator of Cosmic-Ray Energy

We measure the energy emitted by extensive air showers in the form of radio emission in the frequency range from 30 to 80 MHz. Exploiting the accurate energy scale of the Pierre Auger Observatory, we obtain a radiation energy of 15.8 \pm 0.7 (stat) \pm 6.7 (sys) MeV for cosmic rays with an energy of 1 EeV arriving perpendicularly to a geomagnetic field of 0.24 G, scaling quadratically with the cosmic-ray energy. A comparison with predictions from state-of-the-art first-principle calculations shows agreement with our measurement. The radiation energy provides direct access to the calorimetric energy in the electromagnetic cascade of extensive air showers. Comparison with our result thus allows the direct calibration of any cosmic-ray radio detector against the well-established energy scale of the Pierre Auger Observatory.Comment: Replaced with published version. Added journal reference and DOI. Supplemental material in the ancillary file

Sloan Digital Sky Survey IV: Mapping the Milky Way, Nearby Galaxies, and the Distant Universe

We describe the Sloan Digital Sky Survey IV (SDSS-IV), a project encompassing three major spectroscopic programs. The Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2) is observing hundreds of thousands of Milky Way stars at high resolution and high signal-to-noise ratios in the near-infrared. The Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey is obtaining spatially resolved spectroscopy for thousands of nearby galaxies (median $z\sim 0.03$). The extended Baryon Oscillation Spectroscopic Survey (eBOSS) is mapping the galaxy, quasar, and neutral gas distributions between $z\sim 0.6$ and 3.5 to constrain cosmology using baryon acoustic oscillations, redshift space distortions, and the shape of the power spectrum. Within eBOSS, we are conducting two major subprograms: the SPectroscopic IDentification of eROSITA Sources (SPIDERS), investigating X-ray AGNs and galaxies in X-ray clusters, and the Time Domain Spectroscopic Survey (TDSS), obtaining spectra of variable sources. All programs use the 2.5 m Sloan Foundation Telescope at the Apache Point Observatory; observations there began in Summer 2014. APOGEE-2 also operates a second near-infrared spectrograph at the 2.5 m du Pont Telescope at Las Campanas Observatory, with observations beginning in early 2017. Observations at both facilities are scheduled to continue through 2020. In keeping with previous SDSS policy, SDSS-IV provides regularly scheduled public data releases; the first one, Data Release 13, was made available in 2016 July

Sloan Digital Sky Survey IV: mapping the Milky Way, nearby galaxies, and the distant universe

We describe the Sloan Digital Sky Survey IV (SDSS-IV), a project encompassing three major spectroscopic programs. The Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2) is observing hundreds of thousands of Milky Way stars at high resolution and high signal-to-noise ratios in the near-infrared. The Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey is obtaining spatially resolved spectroscopy for thousands of nearby galaxies (median ). The extended Baryon Oscillation Spectroscopic Survey (eBOSS) is mapping the galaxy, quasar, and neutral gas distributions between and 3.5 to constrain cosmology using baryon acoustic oscillations, redshift space distortions, and the shape of the power spectrum. Within eBOSS, we are conducting two major subprograms: the SPectroscopic IDentification of eROSITA Sources (SPIDERS), investigating X-ray AGNs and galaxies in X-ray clusters, and the Time Domain Spectroscopic Survey (TDSS), obtaining spectra of variable sources. All programs use the 2.5 m Sloan Foundation Telescope at the Apache Point Observatory; observations there began in Summer 2014. APOGEE-2 also operates a second near-infrared spectrograph at the 2.5 m du Pont Telescope at Las Campanas Observatory, with observations beginning in early 2017. Observations at both facilities are scheduled to continue through 2020. In keeping with previous SDSS policy, SDSS-IV provides regularly scheduled public data releases; the first one, Data Release 13, was made available in 2016 July

The Seventeenth Data Release of the Sloan Digital Sky Surveys: Complete Release of MaNGA, MaStar and APOGEE-2 Data

This paper documents the seventeenth data release (DR17) from the Sloan Digital Sky Surveys; the fifth and final release from the fourth phase (SDSS-IV). DR17 contains the complete release of the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey, which reached its goal of surveying over 10,000 nearby galaxies. The complete release of the MaNGA Stellar Library (MaStar) accompanies this data, providing observations of almost 30,000 stars through the MaNGA instrument during bright time. DR17 also contains the complete release of the Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2) survey which publicly releases infra-red spectra of over 650,000 stars. The main sample from the Extended Baryon Oscillation Spectroscopic Survey (eBOSS), as well as the sub-survey Time Domain Spectroscopic Survey (TDSS) data were fully released in DR16. New single-fiber optical spectroscopy released in DR17 is from the SPectroscipic IDentification of ERosita Survey (SPIDERS) sub-survey and the eBOSS-RM program. Along with the primary data sets, DR17 includes 25 new or updated Value Added Catalogs (VACs). This paper concludes the release of SDSS-IV survey data. SDSS continues into its fifth phase with observations already underway for the Milky Way Mapper (MWM), Local Volume Mapper (LVM) and Black Hole Mapper (BHM) surveys

The 13th Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the SDSS-IV Survey Mapping Nearby Galaxies at Apache Point Observatory

The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) began observations in July 2014. It pursues three core programs: APOGEE-2,MaNGA, and eBOSS. In addition, eBOSS contains two major subprograms: TDSS and SPIDERS. This paper describes the first data release from SDSS-IV, Data Release 13 (DR13), which contains new data, reanalysis of existing data sets and, like all SDSS data releases, is inclusive of previously released data. DR13 makes publicly available 1390 spatially resolved integral field unit observations of nearby galaxies from MaNGA,the first data released from this survey. It includes new observations from eBOSS, completing SEQUELS. In addition to targeting galaxies and quasars, SEQUELS also targeted variability-selected objects from TDSS and X-ray selected objects from SPIDERS. DR13 includes new reductions ofthe SDSS-III BOSS data, improving the spectrophotometric calibration and redshift classification. DR13 releases new reductions of the APOGEE-1data from SDSS-III, with abundances of elements not previously included and improved stellar parameters for dwarf stars and cooler stars. For the SDSS imaging data, DR13 provides new, more robust and precise photometric calibrations. Several value-added catalogs are being released in tandem with DR13, in particular target catalogs relevant for eBOSS, TDSS, and SPIDERS, and an updated red-clump catalog for APOGEE.This paper describes the location and format of the data now publicly available, as well as providing references to the important technical papers that describe the targeting, observing, and data reduction. The SDSS website, http://www.sdss.org, provides links to the data, tutorials and examples of data access, and extensive documentation of the reduction and analysis procedures. DR13 is the first of a scheduled set that will contain new data and analyses from the planned ~6-year operations of SDSS-IV.PostprintPeer reviewe