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Bioelectronic Measurement and Feedback Control of Molecules in Living Cells(1.81 MB)

Date:
October 2, 2017
Published in:
Nature Scientific Reports, vol. 7
Type:
Journal Article
Topic:

Summary

We describe an electrochemical measurement technique that enables bioelectronic measurements of reporter proteins in living cells as an alternative to traditional optical fluorescence. Using electronically programmable microfluidics, the measurement is in turn used to control the concentration of an inducer input that regulates production of the protein from a genetic promoter. The resulting bioelectronic and microfluidic negative-feedback loop then serves to regulate the concentration of the protein in the cell. We show measurements wherein a user-programmable set-point precisely alters the protein concentration in the cell with feedback-loop parameters affecting the dynamics of the closed-loop response in a predictable fashion. Our work does not require expensive optical fluorescence measurement techniques that are prone to toxicity in chronic settings, sophisticated time-lapse microscopy, or bulky/expensive chemo-stat instrumentation for dynamic measurement and control of biomolecules in cells. Therefore, it may be useful in creating a: cheap, portable, chronic, dynamic, and precise all-electronic alternative for measurement and control of molecules in living cells.

Wind Information Requirements for NextGen Operations Phase 5 Report(13.64 MB)

Date:
August 22, 2017
Published in:
Project Report ATC-439, MIT Lincoln Laboratory
Type:
Project Report
Topic:

Summary

NextGen applications with time-based control elements, such as required time of arrival (RTA) at a meter fix under 4D trajectory-based operations (4D-TBO)/time of arrival control (TOAC) procedures or assigned spacing goal between aircraft under Interval Management (IM) procedures, are subject to the quality of the atmospheric forecast utilized by participating aircraft. The work described in this report summarizes the major activities conducted in the current phase of this program which builds upon prior work.

Fluidic Microoptics with Adjustable Focusing and Beam Steering for Single Cell Optogenetic

Date:
July 10, 2017
Published in:
Optics Express, vol. 25, issue 14
Type:
Journal Article
Topic:

Summary

Electrically controlled micron-scale liquid lenses have been designed, fabricated and demonstrated, that provide both adjustable focusing and beam steering, with the goal of applying them to optogenetic in vivo mapping of brain activity with single cell resolution. The liquid lens is formed by the interface between two immiscible liquids which are contained in a conically tapered lens cavity etched into a fused silica substrate. Interdigitated electrodes have been patterned along the sidewall of the taper to control the liquid lens curvature and tilt. Microlenses with apertures ranging in size from 30 to 80 μm were fabricated and tunable focusing ranging from 0.25 to 3 mm and beam steering of ± 1 degree have been demonstrated.

Open-Source, Community-Driven Microfluidics with Metafluidics

Date:
June 7, 2017
Published in:
Nature Biotechnology, vol. 35, no. 6
Type:
Journal Article
Topic:

Summary

Microfluidic devices have the potential to automate and miniaturize biological experiments, but open-source sharing of device designs has lagged behind sharing of other resources such as software. Synthetic biologists have used microfluidics for DNA assembly, cell-free expression, and cell culture, but a combination of expense, device complexity, and reliance on custom set-ups hampers their widespread adoption. We present Metafluidics, an open-source, community-driven repository that hosts digital design files, assembly specifications, and open-source software to enable users to build, configure, and operate a microfluidic device. We use Metafluidics to share designs and fabrication instructions for both a microfluidic ring-mixer device and a 32-channel tabletop microfluidic controller. This device and controller are applied to build genetic circuits using standard DNA assembly methods including ligation, Gateway, Gibson, and Golden Gate. Metafluidics is intended to enable a broad community of engineers, DIY enthusiasts, and other nontraditional participants with limited fabrication skills to contribute to microfluidic research.

Re-engineering Artificial Muscle with Microhydraulics

Date:
June 5, 2017
Published in:
Nature Microsystems & Nanoengineering, vol. 3
Type:
Journal Article
Topic:

Summary

We introduce a new type of actuator, the microhydraulic stepping actuator (MSA), which borrows design and operational concepts from biological muscle and stepper motors. MSAs offer a unique combination of power, efficiency, and scalability not easily achievable on the microscale. The actuator works by integrating surface tension forces produced by electrowetting acting on scaled droplets along the length of a thin ribbon. Like muscle, MSAs have liquid and solid functional components and can displace a large
fraction of their length. The 100 μm pitch MSA presented here already has an output power density of over 200 W kg− 1, rivaling the most powerful biological muscles, due to the scaling of surface tension forces, MSA’s power density grows quadratically as its dimensions are reduced.

Report on the 2016 CoSPA and Traffic Flow Impact Operational Demonstration(4.64 MB)

Date:
June 1, 2017
Published in:
Project Report ATC-433, MIT Lincoln Laboratory
Type:
Project Report
Topic:

Summary

The 2016 Storm Prediction for Aviation (CoSPA) Demonstration was conducted from 1 June to 31 October 2016. As part of the demonstration, Federal Aviation Administration (FAA) facilities and commercial airlines were visited by MIT Lincoln Laboratory (MIT LL) observers, including initial training visits. Targeted field observations were conducted to gather information on how the CoSPA weather forecast was used in operations, to obtain feedback on new capabilities, and to collect comments for improvement.

Raman Detection of a Single Airborne Aerosol Particles of Isovanillin(3.09 MB)

Date:
May 24, 2017
Published in:
AIP Advances, vol. 7, no. 5
Type:
Journal Article

Summary

Raman spectroscopy of trapped single aerosol particles has been reported previously. However, detection of single aerosol particles via Raman spectroscopy in a flowing system has not been yet reported. In this paper, we describe the first detection of single 3 um flowing airborne aerosol particles flowing through a Raman system, which is a simplified version of the previously reported system with a 532-nm, 10W cw double-pass laser, 532-nm isolator, and double-sided collection optics. The current system has single-pass laser, no 532-nm isolator, and single-sided collection optics. Previous Raman detection of single aerosol particles has been made using trapped particles.

Wind Information Requirements for NextGen Applications Phase 4 Final Report(5.87 MB)

Date:
March 6, 2017
Published in:
Project Report ATC-431, MIT Lincoln Laboratory
Type:
Project Report
Topic:

Summary

Many NextGen applications depend on access to high accuracy wind data due to time-based control elements, such as required time of arrival at a meter fix under 4D-Trajectory-Based Operations/Time of Arrival Control procedures or compliance to an assigned spacing goal between aircraft under Interval Management procedures. The work described in this report summarizes the activities conducted in FY15, which builds upon prior work.

Characterization of Nitrated Sugar Alcohols by Atmospheric Pressure Chemical-ionization Mass Spectrometry

Date:
February 28, 2017
Published in:
Rapid Communications in Mass Spectrometry, vol. 31, no. 4
Type:
Journal Article

Summary

The nitrated sugar alcohols mannitol hexanitrate (MHN), sorbitol hexanitrate (SHN) and xylitol pentanitrate (XPN) are in the same class of compounds as the powerful military-grade explosive pentaerythritol tetranitrate (PETN) and the homemade explosive erythritol tetranitrate (ETN) but, unlike for PETN and ETN, ways to detect MHN, SHN and XPN by mass spectrometry (MS) have not been fully investigated.

Approaches for Language Identification in Mismatched Environments

Date:
December 13, 2016
Published in:
Proceedings of SLT 2016, San Diego, Calif.
Type:
Conference Paper

Summary

In this paper, we consider the task of language identification in the context of mismatch conditions. Specifically, we address the issue of using unlabeled data in the domain of interest to improve the performance of a state-of-the-art system.