Departmental Seminars

Spring 2017

 

Jan 26, 2017
10:40 AM
BTEC 135

Dr. Nathan Crook
Washington University in St. Louis

The human large intestine houses trillions of microorganisms which collectively form the highly diverse microbial community known as the gut microbiota. The gut microbiota performs many functions critical to the maintenance of health, including extraction of nutrients from food, production of vitamins, and defense against pathogens. Like an organ, disturbances to the structure of the gut microbiota can have significant negative impacts to the human host, including obesity, malnutrition, and cancer. However, the gut microbiota is currently unique among organs in that it is highly engineerable, enabling improvement of function by substituting beneficial microbes for less desirable ones. These exogenous beneficial microbes are termed “probiotics” and their close contact with both their human host, as well as other gut bacteria, raises exciting therapeutic prospects, including the provision of additional metabolic functions, modulation of the host immune response, or competitive exclusion of pathogens. However, these applications remain out of reach due to insufficient metabolic activities of engineered strains, as well as the low residence time of most probiotics within the gut. In this talk, I will first describe a high-throughput method which accelerates gene and pathway evolutionary engineering through an in vivo, continuous process. Then, I will show exciting data from a culture-independent bioprospecting approach for increasing the residence time and altering the biogeography of probiotic strains within the gut. Taken together, this work has the potential to significantly improve our understanding and use of probiotics while providing a framework for developing robust chassis strains for future synthetic biology efforts in the human gut microbiota.

Jan 30, 2017
10:40 AM
Room 1011, EB1

Dr. Scott Diamond
University of Pennsylvania

Excessive bleeding and clotting represent the two extremes of blood function that often concern patients and their doctors.  Hundreds of spatiotemporal reactions proceed within activating platelets and the polymerizing plasma as blood clots under flow.  Microfluidic devices are ideal for recreating transport physics and hemodynamic forces.   We have validated several devices to study hemophilia, combinatorial platelet receptor function, drug responses, platelet quorum sensing, and von Willebrand Factor (vWF) assembly in extreme stenotic flows.  Using high throughput experimentation of platelet metabolism, we obtained a large set of platelet calcium responses to combinatorial activators in order to train a neural network (NN) model of platelet activation for several individuals. Each NN model was then embedded into a multiscale kinetic Monte Carlo/finite element/lattice Boltzmann simulation of stochastic platelet deposition under flow.  Simulations predicted the unique clot buildup dynamics for each donor and responses to various pharmacological inhibitors as measured in microfluidic assays. This sets the stage for patient-specific systems biology and point-of-care microfluidic diagnostics.

Feb 6, 2017
10:40 AM
Room 1011, EB1

Dr. Rodolphe Barrangou
North Carolina State University

CRISPR-Cas systems provide adaptive immunity against invasive genetic elements in many bacteria and most archaea. Recently, the molecular machinery from CRISPR-Cas immune systems has been repurposed to drive genome editing in eukaryotes. Indeed, programmable DNA cleavage using CRISPR-Cas9 enables efficient, site-specific genome engineering in single cells and whole organisms. Other applications of versatile CRISPR-based technologies include controlling transcription, modifying epigenomes, conducting genome-wide screens and imaging chromosomes. Beyond biomedical applications, CRISPR technologies are now being used to expedite crop and livestock breeding, engineer new antimicrobials and control disease-carrying insects with gene drives. I will discuss the biological function and repurposing of CRISPR-Cas systems, and highlight applications in bacteria, illustrating the potential of this versatile and transformative technology.

Feb 10, 2017
3 PM
Room 1025, EB2

Dr. Ian Manners
University of Bristol

Although chemical synthesis has evolved to a relatively advanced state, the ability to prepare uniform samples of materials of controlled shape, size, and structural hierarchy on a length scale from 10 nm – 100 µm is still in its relative infancy and currently remains the virtually exclusive domain of biology. In this talk a promising new route to well-defined 1D and 2D materials within this size regime, termed “living crystallization-driven living self-assembly” (CDSA), will be described. The “seeded growth” characteristic of living CDSA means that the process can be regarded as a type of “living supramolecular polymerization” that is analogous to living covalent (e.g. anionic) polymerizations of molecular monomers and also to biological “nucleation-elongation” processes such as amyloid fiber growth. Living CDSA was discovered as a result of an investigation of the solution self-assembly behavior of block copolymers with crystallizable polyferrocenylsilane (PFS) metalloblocks but has now been extended to an array of block copolymers with crystallisable organic blocks, including pi conjugated or biodegradable materials, and also to molecular amphiphiles that form pi-stacked supramolecular polymeric assemblies. Potential applications exist in areas from nanoelectronics to delivery vehicles.

Feb 13, 2017
10:40 AM
Room 1011, EB1

Dr. Hyunhyub Ko
UNIST, Korea

Flexible electronic skins with high tactile sensitivities have gained great attentions in the fields of wearable sensors, robotic skins, and biomedical diagnostics. In human fingertip skins,fingerprint patterns and interlocked epidermal-dermal microridges have critical roles in amplifying and transferring tactile signals to various mechanoreceptors, enabling spatio-temporal perception of various static and dynamic tactile
signals. Here, mimicking the structures and functions of fingertip skin, we introduce highly-sensitive, multifunctional, and stretchable electronic skins.

Inspired by the interlocked microstructures found in epidermal-dermal ridges in human skin, piezoresistive interlocked microdome arrays are employed for the demonstration of stress-direction-sensitive, stretchable electronic skins. We show that interlocked microdome arrays
possess highly direction-sensitive sensitive detection capability of various mechanical stimuli including normal, shear, stretching, bending, and twisting forces. We also demonstrate that ferroelectric skins with fingerprint-like patterns and interlocked microstructures can detect and discriminate multiple spatio-temporal tactile stimuli including static and dynamic pressure, vibration, and temperature with high sensitivities. Finally, we demonstrate that stretchable electronic skins attached on the human skin can be used as wearable healthcare monitoring devices, which are able to distinguish various mechanical stimuli applied in different directions, selectively
monitor different intensities and directions of air flows and vibrations, and sensitively monitor human breathing flows and voice vibrations. In addition, dynamic touch sensing ability is employed for precise detection of acoustic sounds, and discrimination of various surface textures.

Feb 20, 2017
10:40 AM
Room 1011, EB1

Dr. Mauricio Futran
Johnson & Johnson

Ollis Lecture

Today J&J products touch 1 billion lives daily. By 2030 the world will be 8.5 billion people and J&J seeks to touch 2 billion lives. With a median per capita income of $3000 and many healthcare products becoming more complex, a disruptive shift is required in all areas of how care is developed and produced.

Current technology for product manufacturing, process development, clinical development and regulatory interaction are insufficient. Tomorrow’s healthcare product requirements are; affordable and patient centric medicines; drivers of disease outcomes; flexible with respect to demand fluctuation; compliant with regional manufacturing and regulatory laws.

The solution to some of these problems lies in enhanced product and process science and engineering. In Technical Operations in Janssen Supply Chain we are working towards this goal, on many fronts and for a multitude of product types. In Solids Manufacturing we are implementing continuous processes pared with real time product release to enhance by an order of magnitude our flexibility in product supply. In large molecule manufacturing we are implementing real time multi-variate monitoring and optimization methods to decrease the number of upsets, reduce the burden to handle deviations and ultimately allow faster plant to plant transfers. In the area of mechanistic modeling and process analytical technology (PAT) we are constructing models of our main process operations in several areas to allow model or PAT supported parameter range setting, reduce our validation requirements, and make equipment type changes possible. These steps are at first incremental, but they lead up to a fundamental shift towards ANSI/ISA- 88 standard based manufacturing. Here all products are produced based on a recipe and can be transferred from facility to facility with minimal additional testing and validation within a plug-and –play environment. This approach will extend to encompass product families such that we can manufacture products closer to what the customer needs in quality, price and quantity with minimal response time or delay. In the end, we seek to serve a bigger world in a sustainable way.      

Feb 27, 2017
10:40 AM
Room 1011, EB1

Dr. Robert Prud’homme
Princeton University

We have developed a block-copolymer-directed, kinetically-controlled self-assembly process called Flash NanoPrecipitation (FNP) to produce 50-400 nm nanocarriers. The scalability of the process from medchem samples of 1 mg up to 1000 kg/day makes the approach especially significant. It has been successfully scaled to produce GMP nanocarriers for human trials. Successful nanoparticle production involves controlling micromixing to effect supersaturations as high as 10,000 in 1.5 ms, and then controlling nucleation and growth rates to match block copolymer assembly rates. The rapid assembly enables the encapsulation of multiple drugs and imaging agents into the same nanoparticle. The continuous process enables flexible batch sizes. The flexibility of the assembly process enables the preparation of imaging nanoparticles based on fluorescence, PET, xray, MRI, and photoacoustic imaging. Importantly, the single step assembly, avoids the difficult synthesis and purification processes that characterize most nanoparticle processes.

A new “inverse” process enables the encapsulation of biologics (peptides, oligonucleotides, antibiotics, and proteins) in nanoparticles at loadings of up to 90% by weight, without burst release and at 90%+ encapsulation efficiency. This opens up new possibilities for the controlled delivery of biologics and depot delivery.

Targeting is effected by conjugating targeting ligands to the PEG chains prior to assembly. For ligands below 14 kD the nanocarrier targeting functionality is determined by the stoichiometry of the feed stream. This greatly simplifies the quantification of ligand density on the nanocarrier surface, and eliminates issues in purification of excess ligands that occur during most post-assembly conjugation schemes. Examples of mannose targeting to macrophages and VEGF dimers to epithelial cells will be shown. Finally, the extension of a new process developed by Andrew Tsourkas, U Penn, enables the functionalization of nanoparticles with antibodies using light-activated protein G binding.

Mar 13, 2017
10:40 AM
Room 1011, EB1

Dr. Rajesh Naik
Air Force Research Laboratory

Bidoyyomolecules are being exploited in the synthesis, assembly and functionalization of nanomaterials. There has been an ever increasing interest in understanding the interaction between biomolecules and nanomaterials allows researchers to exploit unique and diverse functions of biomolecules to provide opportunities in developing novel concepts, as well as new classes of materials and devices. The knowledge gained in understanding how biological materials are constructed and function has enabled the design of bioinspired/derived functional materials with tailored properties. We have employed experimental and computational approaches to understand structure-function relationships for the development of biomimetic materials, tailoring interfacial properties features and fabricating functional materials for a variety of applications. In this talk, I will highlight our efforts on using our fundamental understanding of biomolecular interactions, factors that influence bio-nanomaterials interactions and demonstrate the fabrication of biomimetic materials for sensing, catalysis and decontamination applications.

Mar 20, 2017
10:40 AM
Room 1011, EB1

Dr. Jingguang Chen
Columbia University

Ocean acidification and climate change are expected to be two of the most difficult scientific challenges of the 21 st century. Converting CO2 into valuable chemicals and fuels is one of the most practical routes for reducing CO2 emissions while fossil fuels continue to dominate the energy sector. The catalytic reduction of CO2 by H2 can lead to the formation of three types of products: CO through the reverse water-gas shift (RWGS) reaction [1], methanol via selective hydrogenation [2], and hydrocarbons [3]. Our research approaches involve the combination of DFT calculations and surface science studies over single crystal surfaces, evaluations over supported catalysts, and in-situ characterization under reaction conditions. In the current talk we will present some of our recent results in CO2 conversion via both heterogenerous catalysis [4] and electrocatalysis [5]. We will also discuss the generation of CO2–free H2 [6,7], which is critical for net CO2 reduction. We will conclude by discussing some challenges and opportunities in this important research field [8].

References:

[1] M.D. Porosoff, X. Yang, J.A. Boscoboinik, and J.G. Chen, “Molybdenum carbide as alternative catalysts to precious metals for highly selective reduction of CO 2 to CO”, Angewandte Chemie International Edition, 53 (2014) 6705.
[2] X. Yang, S. Kattel, S.D. Senanayake, J.A. Boscoboinik, X. Nie, J. Graciani, J.A. Rodriguez, P. Liu, D.J. Stacchiola and J.G. Chen, “Low pressure CO 2 hydrogenation to methanol over gold nanoparticles activated on a CeOx/TiO 2 interface”, Journal of the American Chemical Society, 137 (2015) 10104.
[3] S. Kattel, W. Yu, X. Yang, B. Yan, Y. Huang, W. Wan, P. Liu and J.G. Chen, “CO 2 Hydrogenation on Oxide-supported PtCo Catalysts: Fine-tuning Selectivity using Oxide Supports”, Angewandte Chemie International Edition, 55 (2016) 7968-7973.
[4] M.D. Porosoff, M. Myint, S. Kattel, Z. Xie, E. Gomez, P. Liu and J.G. Chen, “Identifying different types of catalysts for CO 2 reduction by ethane through dry reforming and oxidative dehydrogenation”, Angewandte Chemie International Edition, 54 (2015) 15501.
[5] Q. Lu, J. Rosen, Y. Zhou, G.S. Hutchings, Y.C. Kimmel, J.G. Chen and F. Jiao, “A Highly Selective and Efficient Electrocatalyst for Carbon Dioxide Reduction”, Nature Communications, 5 (2014) 3242.
[6] M.R. Stonor, T.E. Fergusonb, J.G. Chen and A.-H. Park, “Biomass Conversion to H2 with Substantially Suppressed CO 2 Formation in the Presence of Group I & Group II Hydroxides and a Ni/ZrO 2 Catalyst”, Energy & Environmental Science, 8 (2015) 1702.
[7] Q. Lu, G.S. Hutchings, W. Yu, Y. Zhou, R.V. Forest, R. Tao, J. Rosen, B.T. Yonemoto1, Z. Cao, H. Zheng, J.Q. Xiao, F. Jiao and J.G. Chen, “Highly Porous Non-precious Bimetallic Electrocatalysts for Efficient Hydrogen Evolution”, Nature Communications, 6 (2015) 6567
[8] M.D. Porosoff, B. Yan and J.G. Chen, “Catalytic reduction of CO 2 by H 2 for synthesis of CO, methanol and hydrocarbons: Challenges and opportunities”, Energy & Environmental Science, 9 (2016) 62.

Mar 27, 2017
10:40 AM
Room 1011, EB1

Dr. Liang-Shih Fan
Ohio State University

McCabe Lecture

Chemical looping technology is a manifestation of the interplay among such key elements of metal oxide reaction engineering and particle science and technology as particle synthesis, reactivity and mechanical properties, flow stability and contact mechanics, gas-solid reaction engineering and particulates system engineering. This presentation will describe the fundamental and applied features of modern chemical looping technology in the context of the circulating fluidized bed platform that utilizes fossil and other carbonaceous feedstock. It will discuss the reaction chemistry, ionic diffusion mechanisms, metal oxide synthesis and thermodynamics, reactor design, and system engineering along with energy conversion efficiency and economics of the chemical looping processes for full and partial or selective oxidation for electricity, syngas and chemicals production. The Ohio States University has developed a number of advanced chemical looping combustion, gasification, reforming, and chemical synthesis processes which will be highlighted in this presentation. 

Apr 3, 2017
10:40 AM
Room 1011, EB1

Dr. Jeff Klauda
University of Maryland

Alcohols have a strong influence in cellular biology and alter the properties of lipid membranes. This is one limiting factor in microbial production of chemicals and fuels in that cells cannot survive in

solutions that contain a moderate level of the produced chemical or fuel. Since cellular membranes consist of a wide array of lipid types, we have been studying the influence of lipid head group on its ability to protect the membrane from the toxic effects of ethanol. Molecular dynamics (MD) simulations have probed common lipids found in yeast plasma membranes and it was found that the phosphatidylcholine lipid was most influenced by ethanol and phosphatidylserine was the least. In collaboration with Dr. Laura Jarboe at Iowa State University, we are currently probing the effects of ethanol (and other chemicals) on the E. Coli inner membrane with a goal to genetically alter lipid composition to develop more tolerant bacterial strains to chemical stress.

In a separate project, we are aiming to understand the mechanism of lipid exchange between cellular organelles involved in certain human diseases and conditions. This involves proteins that aid in lipid transport by forming membrane contact sites (MCS). One example is the oxysterol binding protein homologues (Osh) with Osh4 known to exchange phosphatidylinositol 4-phosphate lipids regulated by ergosterol. This protein contains a lipid packing sensing peptide classified as an amphipathic lipid packing sensor (ALPS) like motif that is believed to sense membrane curvature. We have used µs simulations to probe the binding mechanism of the full-length protein to single model membranes. Our extensive simulations have shown a binding confirmation in agreement with experiment but one that prevents lipid exchange between membranes. MD simulations were then used to probe the mechanism of the ALPS binding motif with all-atom membranes and a method to enhance binding, i.e., the Highly Mobile Membrane-Mimetic Model (BJ, 102: p2130). This initial work has provided a biophysical understanding of Osh4 binding to single membranes and will allow for future studies on how this protein facilitates MCS and lipid exchange between membranes.

Apr 10, 2017
10:40 AM
Room 1011, EB1

Dr. Frank Doyle
Harvard University

Type 1 diabetes mellitus (T1DM) is a chronic autoimmune disease affecting approximately 35 million individuals world-wide, with associated annual healthcare costs in the US estimated to be approximately $15 billion. Current treatment requires either multiple daily insulin injections or continuous subcutaneous (SC) insulin infusion (CSII) delivered via an insulin infusion pump. Both treatment modes necessitate frequent blood glucose measurements to determine the daily insulin requirements for maintaining near-normal blood glucose levels.

More than 30 years ago, the idea of an artificial endocrine pancreas for patients with type 1 diabetes mellitus (T1DM) was envisioned. The closed-loop concept consisted of an insulin syringe, a blood glucose analyzer, and a transmitter. In the ensuing years, a number of theoretical research studies were performed with numerical simulations to demonstrate the relevance of advanced process control design to the artificial pancreas, with delivery algorithms ranging from simple PID, to H-infinity, to model predictive control. With the advent of continuous glucose sensing, which reports interstitial glucose concentrations approximately every minute, and the development of hardware and algorithms to communicate with and control insulin pumps, the vision of closed-loop control of blood glucose is approaching a reality.

In the last 15 years, our research group has been working with medical doctors on clinical demonstrations of feedback control algorithms for the artificial pancreas. In this talk, I will outline the difficulties inherent in controlling physiological variables, the challenges with regulatory approval of such devices, and will describe a number of process systems engineering algorithms we have tested in clinical experiments for the artificial pancreas.

Apr 17, 2017
10:40 AM
Room 1011, EB1

Dr. Jonathan Stallings
North Carolina State University

Many scientific researchers are exposed to statistics and basic principles of DOX in their graduate training, but introductory design courses often ignore more recent developments in the area. They also give the impression that failing to do one of the cookbook designs will yield a poorly conducted experiment and uninformative analysis. In this talk, I will review some of the basic principles that lead us to these standard designs and show how these principles may still hold in unconventional designs. Case studies will motivate design scenarios that I believe are encountered by researchers in the CBE department, including screening designs, split plot designs, mixture experiments, and computer experiments. JMP software, available for free to all NCSU faculty and students, will be used throughout and shown to be a powerful resource for generating custom designs and analyzing data. I hope this talk will generate future collaborations between the CBE and Statistics departments.

Apr 24, 2017
10:40 AM
Room 1011, EB1

Dr. Miao Yu
University of South Carolina

There are so many important molecules in nature (H2O, O2, CH4, etc.) and produced in industrial processes (C2H4, C3H6, etc.), which are well mixed with other components and need to be selectively extracted/produced for their beneficial uses. Size/shape differences between molecules usually exist and thus can be effectively utilized to distinguish them. My research is focused on rationally designing and fabricating nanoporous structures to distinguish molecules by size/shape differences and thus realize highly selective extraction/production in separation and catalysis processes. The basic strategy is to take advantage of the special properties of nanomaterials, such as 2-dimensional (2-D) morphology of graphene/graphene oxide (GO) and molecular-sized pores of zeolites, and/or fundamental coating/membrane growth and deposition mechanisms to precisely manipulate pore sizes. In this talk, I will present our recent research on thin coating deposition by molecular layer deposition (MLD) and engineering zeolite- and GO-based nanoporous structures, and their potential separation applications as adsorbents and membranes. These novel concepts and/or novel nanoporous structures may have wide applications on separation and catalysis.