הפקולטה להנדסה ע"ש איבי ואלדר פליישמן

EE Seminar: Gilad Poker

~~
Gilad Poker,
M.Sc. student under the supervision of Prof. Michael Margaliot

Wednesday, January 7, 2015 at 15:00
Room 011, Kitot Bldg., Faculty of Engineering

Maximizing Protein Translation Rate in the Ribosome Flow Model

Abstract

Translation is an important stage in gene expression. During this stage, macro-molecules called ribosomes, travel along the mRNA strand linking amino-acids together in a specific order to create a functioning protein.
An important question, related to many biomedical disciplines, is how to maximize protein production.
Indeed, translation is known to be one of the most energy consuming processes in the cell, and it is natural to assume that evolution shaped this process so that it maximizes the protein production rate. If this is indeed so then one can estimate various parameters of the translation machinery by solving an appropriate mathematical optimization problem.
The same problem also arises in the context of synthetic biology, namely, re-engineer heterologous genes in order to maximize their translation rate in a host organism.
We consider the problem of maximizing the protein production rate using a computational model for translation-elongation called the ribosome flow model (RFM). This model describes the flow of the ribosomes along an mRNA chain of length n using a set of n first-order nonlinear ordinary differential equations.
We show that the steady-state translation rate in the RFM is a strictly concave function of its parameters.
This means that the problem of maximizing the translation rate under a suitable constraint always admits a unique solution, and that this solution can be determined using highly-efficient algorithms for solving convex optimization problems.
Furthermore, our analysis shows that the optimal translation rate can be computed based only on the optimal initiation rate and the elongation rate of the codons near the beginning of the ORF.

07 בינואר 2015, 15:00

חדר 011, בניין כיתות חשמל

24 דצמבר 2014

Congratulations to Prof. Amit Gefen who was just elected to be a Fellow of the International Academy of Medical and Biological Engineering.

"The International Academy of Medical and Biological Engineering (IAMBE) is made up of fellows who are recognized for their outstanding contributions to the profession of medical and biological engineering. Election to the Academy is initiated by nominations which are screened by the membership committee of the Academy. The election is conducted by a vote of all Fellows of the Academy."

ברכות ל:

אבישי אייל, אלון באב"ד+ערן סוחר, אילן גולדפרב+אריה רוזין+שחר ריכטר, מיכאל מרגליות+תמיר טולר, וגבור קושה +חדוה שפיצר

שזכו במענקי מחקר של הקרן הלאומית למחקר מדעי יישומי והנדסי (מי"ה)

ברכות לנתן שקד, סלבה קרילוב ודוד מנדלוביץ שזכו במענקי קרן מומנטום של רמות .

Label-free quantitative analysis of sperm cells by interferometric microscopy by Dr. Natan Shaked

A novel phase interferometric technique will allow measuring live sperm cells, without any staining and in a fully quantitative manner. This device will allow the embryologist to select the most suitable sperm cell for in-vitro fertilization (IVF), and is anticipated to substantially increase the success rate of IVF, which stands today on about 30% for woman under 35 years old.

Hyperspectral MEMS (“HSM”) Filter by Prof. D. Mendlovic and Prof. S. Krylov

HSM enables fast and reliable scanning of wavelengths for various sensing, detection and imaging applications. It aims to improve image quality and to equip any standard camera with hyperspectral imaging capabilities. It is a highly accurate, MEMS based, tunable spectral filter with closed loop feedback mechanism. HSM is especially suited for mobile cameras as well as other cameras, spectrometers, medical and industrial cameras, etc. Some of its unique advantages include small form factor, adding hyperspectral functionality to all camera types, wide wavelength range (UV, VIS, NIR, IR), flexible transmission spectra, power efficiency, and low cost.

מאמר של בוריס מלמד התפרסם ב- Nature Physics

Congratulations to Leslie Banks-Sills who was elected for a second, four year term as President of the European Structural Integrity Society (ESIS) http://www.structuralintegrity.eu/ The Society has over 500 members from over 20 countries in Europe. The aims of ESIS include development and extension of knowledge in all aspects of structural integrity, as well as dissemination of that knowledge world-wide with the objectives of improving the safety and performance of engineering equipment, individual components and structures. She is also President of the local organization: Israel Structural Integrity Group (ISIG).

ידיעות נוספות בנושא

סמינר מחלקתי

25 בדצמבר 2014, 12:00

חדר 206 בניין וולפסון

Using models to inform public health policy

Dr. Dan Yamin

Center for Infectious Disease Modeling, School of Public Health, Yale University

Abstract:

The healthcare industry is one of world’s largest and fastest growing industries, with over 7.5% of gross domestic products in most developed countries, including Israel. Using multiple tools from operations research I seek to design and apply theoretical and practical models that capture the interaction among individuals, pharmaceutical companies, and decision makers in dynamic environments. I will present the following three applications and their contribution in shaping health policy: 1) a theoretical epidemiological game model to find the optimal incentive for influenza vaccination, 2) a contact network based model to design a practical vaccination policy to identify the super-spreaders of influenza and prioritizes them for vaccination, and 3) a stochastic transmission model that integrates epidemiological data and data on contacts of patients with Ebola from the current outbreak to evaluate the effect of Ebola progression on transmission and control.

EE Seminar: Prof. Jason L. Speyer

~~(The talk will be given in English)

Prof. Jason L. Speyer
Mechanical and Airspace Engineering Department, University of California, Los Angeles
Thursday, December 25, 2014
11:00 - 12:00
Room 011, Kitot Bldg., Faculty of Engineering

A System Theoretic Approach to the Feedback Control of Channel Flow
Abstract
A framework for determining feedback controllers for the stabilization of three-dimensional channel flow with wall pumping-and-suction control and wall shear measurements is developed using a control theoretic approach. The elements of this approach are the determination of the finite-dimensional model based on the Navier- Stokes equations and the controller development based on the inherent decomposition of the system state and measurement model. Using balanced realization, the model reduction of the nonnormal Orr-Sommerfield system shows the sensitivity of the transfer function and the effect of the pseudo-spectrum due to the balanced model truncation. Finally, it is shown that an upstream travelling wave reduces friction drag, but induces secondary instabilities. It is shown that the dynamics of the steady-state flow induced by a traveling wave must be linearized and decomposed in a frame of reference moving with the traveling wave. The resulting linear time-invariant equations are appropriate for system theoretic feedback control synthesis. A linear controller based on these equations is shown to suppress the secondary instabilities in direct numerical simulations. Although our ultimate goal of driving a turbulent boundary layer to a laminar boundary layer has not yet been achieved, these various steps appear to be bringing us closer to this goal.

25 בדצמבר 2014, 11:00

חדר 011, בניין כיתות-חשמל

Stem Cell Therapies for Skeletal Injuries

סמינר מחלקתי

Stem Cell Therapies for Skeletal Injuries

Dan Gazit PhD, DMD

Skeletal Biotech Laboratory, The Hebrew University–Hadassah Faculty of Dental Medicine, Ein Kerem, Jerusalem, Israel

As the population grows older, our skeleton is subjected to increasing incidents of trauma, cancer and various disorders such as osteoporosis. Vertebral compression fractures are the most common fractures associated with osteoporosis. Approximately 700,000 osteoporosis-related vertebral compression fractures (OVCFs) occur each year in the USA. Multiple publications have shown that mortality risk is increased up to nine-fold following such fractures. It is estimated that about 100,000 cases of severe bone loss in the craniofacial bones and a million non-union fractures in long bones are treated each year. Most of the critical-size bone defects are treated with bone grafts, while OVCFs are often treated with bed rest and pain medication due to lack of effective therapeutic options. Current bone grafts suffer from several disadvantages: autografts have limited availability and often cause prolonged pain and comorbidity. Allografts, on the other hand, are more available but tend to fail due to poor integration. We hypothesized that mesenchymal stem cells (MSCs) could be utilized either to generate a new potent bone graft or to optimize the use of currently available allografts. Our studies included the use of exogenous or endogenous MSCs for the treatment of vertebral fractures and critical size defects in calvaria and long bones. Specifically, we treated osteopenic rats with multiple vertebral fractures by i.v. injections of human MSCs and intermittent administration of recombinant PTH, as an adjuvant to enhance cell homing and differentiation. We also used PTH to enhance the integration of calvaria bone allografts in mice, showing a local effect on osteoprogenitors around the graft. Finally, we used collagen scaffolds to recruit endogenous MSCs to radius bone defects in mice and then delivered a BMP gene to the cells using sonoporation. Our results showed accelerated bone repair and graft integration in all three-injury sites. Furthermore, pilot studies in pig models yielded promising results utilizing the same therapeutic approaches. In summary, we believe that by the right manipulation of either exogenous of endogenous MSCs it is possible to bring novel therapeutic options for unmet clinical needs in orthopedic medicine.

28 בדצמבר 2014, 14:15

הנדסה ביו רפואית

סמינר המחלקה להנדסה ביו רפואית יתקיים ביום ראשון ה 28.12.14 בשעה 14:15

בחדר 315 ,הבניין הרב תחומי ,אוניברסיטת תל אביב

EE Seminar: Dr. Danial Zelazo, Technion

~~(The talk will be given in English)

Speaker: Dr. Daniel Zelazo,
Department of Aerospace Engineering, Technion
Monday, December 29th, 2014
15:00 - 16:00
Room 011, Kitot Bldg., Faculty of Engineering

Distributed Negotiation Methods for Multi-Agent Dynamical Systems

Abstract
Many applications of multi-agent systems assume that all agents in the system are cooperating to achieve a common goal. From an optimization perspective, these systems are attempting to minimize some global objective function in a distributed manner. Other applications, however, may require that each agent in the system behaves selfishly to achieve some local desired objective, but is constrained by certain team goals. In this scenario there must be a compromise between what each individual agent considers optimal and the constraints imposed on the entire team. In this talk, we explore this second scenario and describe a solution method we term the shrinking horizon preference agreement algorithm that allows each agent to distributedly and in real-time negotiate their individual optimal trajectories while satisfying the team constraints. We consider this problem for both fixed and switching communication topologies and in the process reveal connections between distributed optimization algorithms, graph structures, and the classical linear quadratic regulator problem.
Bio: Daniel Zelazo received his BSc. and M.Eng degrees in electrical engineering from MIT in '99 and '01. He spent 2 years working at Texas Instruments in Japan before beginning his PhD at UW under the supervision of Mehran Mesbahi. He received his doctorate in the AeroAstro department in 2009, and in 2010 he began a post-doc at the Institute for Systems Theory and Automatic Control in Stuttgart, Germany. In the fall of 2012 he joined the Faculty of Aerospace Engineering as an assistant prof. at the Technion - Israel Institute of Technology in Haifa, Israel.

29 בדצמבר 2014, 15:00

חדר 011, בניין כיתות-חשמל

סמינר מחלקתי Rachel Ofir

07 בינואר 2015, 15:00

וולפסון 206

School of Mechanical Engineering Seminar
Wednesday, January 7, 2015 at 15:00
Wolfson Building of Mechanical Engineering, Room 206

Condensation in parallel pipes with common headers

Rachel Ofir

MSc Student of Prof. Yehuda Taitel and Prof. Dvora Barnea

In heat exchangers the motive fluid is usually distributed in multiple parallel channels in order to enhance heat transfer by increasing the contact area and at the same time decrease the equipment size. Uniform flow distribution is required to obtaining high performance in heat exchangers. However maldistribution may occur under certain condition, primarily in evaporating systems.

In this work condensation within a parallel pipes system is examined. The studied system is an air cooled condenser comprised of a number of parallel pipes (horizontally oriented) with common headers located at the entrance to the pipes and at exit of the pipes.

Hot n-Pentane flows through the parallel pipes system. Air flows across the pipes and heat is rejected from the hot n-Pentane to the ambient air. In this thesis a model for predicting flow rate distribution in an air cooled condenser is presented.

סמינר מחלקתי

23 בדצמבר 2014, 14:00

חדר 206 בניין וולפסון

Human-Technology Exploration: how do curious agents interact with learning systems?

Dr. Goren Gordon - MIT

Abstract:

People interact with novel technology all the time. How do they explore it? How do new learning systems explore their users to better understand and react to them? In this talk I present recent results from the study of curiosity, both human and artificial. To better understand basic curiosity-driven behaviors, we first studied rodents' exploration of a new environment, where we showed that curious animals optimize their novelty signal-to-noise ratio, so that their novelty input is high, yet stable. Incorporating this insight into an information-theoretic model of hierarchical curiosity loops and novelty management, resulted in a minimal model that can explain and predict many observed behaviors. We showed that people exploring with artificial whiskers followed these same principles. The same model, implemented in robots, results in curious robots that learn about themselves and people interacting with them. Finally, results from a recent study on how children interacted with robots, where human and artificial curiosity are combined in a literacy educational setting, indicate that children can “catch” curiosity from a curious robot in a selective manner. Future work on the study of how adults curiously explore novel technologies, and how these systems explore and personalize to their users concludes the talk.

24.12.14

24 בדצמבר 2014, 14:00

031 Lab Build

You are invited to attend a lecture

Iddo Amit

PhD student under the supervision of Prof. Yossi Rosenwaks

Department of Physical Electronics, School of Electrical Engineering

Tel Aviv University

On the subject:

Functional Imaging of In-situ and Ex-situ Doped Silicon Nanowires

Semiconductor Nanowire-based electronics offers the opportunity to achieve tight control over a precisely defined component, often comprised of the nanowire (NW) itself, which in turn, enables the enhancement of the device performance. Currently, one of the main challenges facing the fabrication process of NW-based electronics is the formation of well-defined doping profiles which are crucial for the fine-tuning of the device behavior.

However, the conventional doping mechanism, where dopants are introduced in-situ during growth, results in both axial and radial inhomogeneous doping profiles which stem from a surface doping mechanism known as vapor-solid (VS) doping. Moreover, in interfaces between different doping types, a region of diffuse boundaries is formed rather than an abrupt transition between the two segments.

We use quantitative Kelvin probe force microscopy (KPFM) and nano-probe scanning Auger spectroscopy to measure both the longitudinal and the radial doping distribution in doped Si nanowires (SiNWs). Our findings shed light on the underlying mechanisms that produce these inhomogeneities by studying P doping profiles of axially modulation-doped SiNWs. We find that both the VLS and the VS mechanisms result in radially inhomogeneous doping, specifically, a lightly doped core surrounded by a heavily doped shell structure. By designing a modulated doping profile, the effects of the two mechanisms can be distinguished. We also discuss the influence of the reservoir effect that significantly broadens the axial doping junctions.

These results are compared to measurements conducted on monolayer contact doped (MLCD) NWs. This ex-situ doping process takes advantage of the precision of electron beam lithography as well as the selectivity and controllability of chemical monolayer formation to produce tailor-made dopant profiles by post-growth doping through the surface.

24 December 2014, at 14:00,

Room 031, Engineering Labs Building

25.12.14

25 בדצמבר 2014, 14:00

011 Kitot

Physical Electronics Dept

You are invited to attend a lecture

Prof. Alan Willner

(Steven and Kathryn Sample Chair in Engineering Rm. EEB 538

Ming Hsieh Dept. of Electrical Engineering

University of Southern California)

High-Capacity Optical and RF Communications using Multiplexing of Multiple Orbital-Angular-Momentum Beams

The ability to multiplex multiple, spatially overlapping data-carrying modes over the same physical medium represents the potential for increasing system capacity and spectral efficiency. Generating different amounts of orbital-angular-momentum (OAM) on different optical beams has emerged as a technique for such mode multiplexing. Each OAM beam is orthogonal and can be efficiently multiplexed and demultiplexed, and OAM is compatible with other forms of multiplexing (e.g., polarization multiplexing and WDM). This presentation will explore the achievements of and challenges to OAM-based optical and RF communication systems, including transmission and switching.

Thursday, December 25, 2014, at 14:00

Room 011, EE- KITOT building

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