Performance Evaluation of a Solar-Powered Regenerative Organic Rankine Cycle in Different Climate Conditions

Directory of Open Access Journals (Sweden)

Emily Spayde

2017-01-01

Full Text Available A model to evaluate the performance of a solar powered regenerative Organic Rankine Cycle (R-ORC using five dry organic fluids: RC318, R227ea, R236ea, R236fa, and R218, is presented in this paper. The system is evaluated in two locations in the U.S.: Jackson, MS and Tucson, AZ. The weather data for each location is used to determine the heat available from the solar collector that could be used by the R-ORC to generate power. Results from the R-ORC performance are compared with a basic ORC using first and second law criteria as well as primary energy consumption (PEC and carbon dioxide emission (CDE savings for both locations. An economic analysis to determine the maximum capital cost for a desired payback period is presented in this paper. A parametric analysis is also performed to study the effect of the turbine efficiency as well as the open feed organic fluid heater intermediate pressure on the system performance. Results indicate that the R-ORC is able to generate more power than the basic ORC for some of the selected working fluids. For the R-ORC, R236ea is the working fluid that show the best performance among the evaluated fluids under the modeled conditions. On the other hand, the basic ORC with R236ea as the working fluid outperformed three of the fluids in the R-ORC. Also, the R-ORC evaluated in Tucson, AZ is able to generate more power, to provide more PEC and CDE savings, and had a higher available capital cost than the R-ORC evaluated in in Jackson, MS.

Investigation of a novel concept for hydrogen production by PEM water electrolysis integrated with multi-junction solar cells

International Nuclear Information System (INIS)

Ferrero, Domenico; Santarelli, Massimo

2017-01-01

Highlights: • A 2D model of a PEM water electrolyzer is developed and validated. • A novel system integrating PEM and multi-junction solar cells is proposed. • The model is applied to the simulation of the novel system. • The integration of PEM and MJ cells enhances the hydrogen production efficiency. - Abstract: A 2D finite element model of a high-pressure PEM water electrolyzer is developed and validated over experimental data obtained from a demonstration prototype. The model includes the electrochemical, fluidic and thermal description of the repeating unit of a PEM electrolyzer stack. The model is applied to the simulation of a novel system composed by a high-temperature, high-pressure PEM electrochemical cell coupled with a photovoltaic multi-junction solar cell installed in a solar concentrator. The thermo-electrochemical characterization of the solar-driven PEM electrolysis system is presented and the advantages of the high-temperature operation and of the direct coupling of electrolyzer and solar cell are assessed. The results show that the integration of the multi-junction cell enhances the performance of the electrolyzer and allows to achieve higher system efficiency compared to separated photovoltaic generation and hydrogen production by electrolysis.

Regenerative medicine blueprint.

Science.gov (United States)

Terzic, Andre; Harper, C Michel; Gores, Gregory J; Pfenning, Michael A

2013-12-01

Regenerative medicine, a paragon of future healthcare, holds unprecedented potential in extending the reach of treatment modalities for individuals across diseases and lifespan. Emerging regenerative technologies, focused on structural repair and functional restoration, signal a radical transformation in medical and surgical practice. Regenerative medicine is poised to provide innovative solutions in addressing major unmet needs for patients, ranging from congenital disease and trauma to degenerative conditions. Realization of the regenerative model of care predicates a stringent interdisciplinary paradigm that will drive validated science into standardized clinical options. Designed as a catalyst in advancing rigorous new knowledge on disease causes and cures into informed delivery of quality care, the Mayo Clinic regenerative medicine blueprint offers a patient-centered, team-based strategy that optimizes the discovery-translation-application roadmap for the express purpose of science-supported practice advancement.

High Thermal Gradient in Thermo-electrochemical Cells by Insertion of a Poly(Vinylidene Fluoride) Membrane

Science.gov (United States)

Hasan, Syed Waqar; Said, Suhana Mohd; Sabri, Mohd Faizul Mohd; Bakar, Ahmad Shuhaimi Abu; Hashim, Nur Awanis; Hasnan, Megat Muhammad Ikhsan Megat; Pringle, Jennifer M.; Macfarlane, Douglas R.

2016-07-01

Thermo-Electrochemical cells (Thermocells/TECs) transform thermal energy into electricity by means of electrochemical potential disequilibrium between electrodes induced by a temperature gradient (ΔT). Heat conduction across the terminals of the cell is one of the primary reasons for device inefficiency. Herein, we embed Poly(Vinylidene Fluoride) (PVDF) membrane in thermocells to mitigate the heat transfer effects - we refer to these membrane-thermocells as MTECs. At a ΔT of 12 K, an improvement in the open circuit voltage (Voc) of the TEC from 1.3 mV to 2.8 mV is obtained by employment of the membrane. The PVDF membrane is employed at three different locations between the electrodes i.e. x = 2 mm, 5 mm, and 8 mm where ‘x’ defines the distance between the cathode and PVDF membrane. We found that the membrane position at x = 5 mm achieves the closest internal ΔT (i.e. 8.8 K) to the externally applied ΔT of 10 K and corresponding power density is 254 nWcm-2 78% higher than the conventional TEC. Finally, a thermal resistivity model based on infrared thermography explains mass and heat transfer within the thermocells.

The use of PEM united regenerative fuel cells in solar- hydrogen systems for remote area power supply

International Nuclear Information System (INIS)

Arun K Doddathimmaiah; John Andrews

2006-01-01

Remote area power supply (RAPS) is a potential early market for renewable energy - hydrogen systems because of the relatively high costs of conventional energy sources in remote regions. Solar hydrogen RAPS systems commonly employ photovoltaic panels, a Proton Exchange Membrane (PEM) electrolyser, a storage for hydrogen gas, and a PEM fuel cell. Currently such systems are more costly than conventional RAPS systems employing diesel generator back up or battery storage. Unitized regenerative fuel cells (URFCs) have the potential to lower the costs of solar hydrogen RAPS systems since a URFC employs the same hardware for both the electrolyser and fuel cell functions. The need to buy a separate electrolyser and a separate fuel cell, both expensive items, is thus avoided. URFCs are in principle particularly suited for use in RAPS applications since the electrolyser function and fuel cell function are never required simultaneously. The present paper reports experimental findings on the performance of a URFC compared to that of a dedicated PEM electrolyser and a dedicated fuel cell. A design for a single-cell PEM URFC for use in experiments is described. The experimental data give a good quantitative description of the performance characteristics of all the devices. It is found that the performance of the URFC in the electrolyser mode is closely similar to that of the stand-alone electrolyser. In the fuel cell mode the URFC performance is, however, lower than that of the stand-alone fuel cell. The wider implications of these findings for the economics of future solar-hydrogen RAPS systems are discussed, and a design target of URFCs for renewable-energy RAPS applications proposed. (authors)

Solar thermochemical and electrochemical research - how they can help reduce the carbon dioxide burden

Energy Technology Data Exchange (ETDEWEB)

Fletcher, E.A. [Minnesota Univ., Minneapolis, MN (United States). Dept. of Mechanical Engineering

1996-07-01

Any process which decreases the use of fossil fuels as a prime energy source will be used only if it is attractive to industry. To be attractive, an alternative energy source must be cost effective. The only alternative prime energy sources which appear likely to be cost effective in the foreseeable future are nuclear fission and the various manifestations of solar. Fission, no matter how well it is engineered on earth, can cause major disasters because of human error; its apparent cost effectiveness is illusory. Thermonuclear fusion energy is no closer to fruition than it was fifty years ago, when it was first proposed. Solar energy is thermonuclear fusion. The source is far removed from humans. We can`t manipulate the safety devices. The realization that one cannot divorce nuclear energy from the hazards of human error and malice is already a given in public policy. Being a 5800K source, solar is most efficiently used when it is directly absorbed at the site of an endothermic reaction at the highest practicable temperature. In recognizing the special thermodynamic attributes of solar energy, for the past 20 years my students and I have explored various solar thermochemical and solar thermoelectrochemical processes. This paper presents a summary of some of our pertinent observations and suggests directions that I believe future research and development should take. (UK)

Hydrogen-Oxygen PEM Regenerative Fuel Cell Energy Storage System

Science.gov (United States)

Bents, David J.; Scullin, Vincent J.; Chang, Bei-Jiann; Johnson, Donald W.; Garcia, Christopher P.

2005-01-01

An introduction to the closed cycle hydrogen-oxygen polymer electrolyte membrane (PEM) regenerative fuel cell (RFC), recently constructed at NASA Glenn Research Center, is presented. Illustrated with explanatory graphics and figures, this report outlines the engineering motivations for the RFC as a solar energy storage device, the system requirements, layout and hardware detail of the RFC unit at NASA Glenn, the construction history, and test experience accumulated to date with this unit.

Regenerative endodontics.

Science.gov (United States)

Simon, S; Smith, A J

2014-03-01

Significant advances in our understanding of the biological processes involved in tooth development and repair at the cellular and molecular levels have underpinned the newly emerging area of regenerative endodontics. Development of treatment protocols based on exploiting the natural wound healing properties of the dental pulp and applying tissue engineering principles has allowed reporting of case series showing preservation of tissue vitality and apexogenesis. To review current case series reporting regenerative endodontics. Current treatment approaches tend to stimulate more reparative than regenerative responses in respect of the new tissue generated, which often does not closely resemble the physiological structure of dentine-pulp. However, despite these biological limitations, such techniques appear to offer significant promise for improved treatment outcomes. Improved biological outcomes will likely emerge from the many experimental studies being reported and will further contribute to improvements in clinical treatment protocols.

Hydrogen-Oxygen PEM Regenerative Fuel Cell Development at NASA Glenn Research Center

Science.gov (United States)

Bents, David J.; Scullin, Vincent J.; Chang, B. J.; Johnson, Donald W.; Garcia, Christopher P.; Jakupca, Ian J.

2006-01-01

The closed-cycle hydrogen-oxygen PEM regenerative fuel cell (RFC) at NASA Glenn Research Center has demonstrated multiple back to back contiguous cycles at rated power, and round trip efficiencies up to 52 percent. It is the first fully closed cycle regenerative fuel cell ever demonstrated (entire system is sealed: nothing enters or escapes the system other than electrical power and heat). During FY2006 the system has undergone numerous modifications and internal improvements aimed at reducing parasitic power, heat loss and noise signature, increasing its functionality as an unattended automated energy storage device, and in-service reliability. It also serves as testbed towards development of a 600 W-hr/kg flight configuration, through the successful demonstration of lightweight fuel cell and electrolyser stacks and supporting components. The RFC has demonstrated its potential as an energy storage device for aerospace solar power systems such as solar electric aircraft, lunar and planetary surface installations; any airless environment where minimum system weight is critical. Its development process continues on a path of risk reduction for the flight system NASA will eventually need for the manned lunar outpost.

Integrated Photoelectrochemical Solar Energy Conversion and Organic Redox Flow Battery Devices

KAUST Repository

Li, Wenjie

2016-09-21

Building on regenerative photoelectrochemical solar cells and emerging electrochemical redox flow batteries (RFBs), more efficient, scalable, compact, and cost-effective hybrid energy conversion and storage devices could be realized. An integrated photoelectrochemical solar energy conversion and electrochemical storage device is developed by integrating regenerative silicon solar cells and 9,10-anthraquinone-2,7-disulfonic acid (AQDS)/1,2-benzoquinone-3,5-disulfonic acid (BQDS) RFBs. The device can be directly charged by solar light without external bias, and discharged like normal RFBs with an energy storage density of 1.15 Wh L−1 and a solar-to-output electricity efficiency (SOEE) of 1.7 % over many cycles. The concept exploits a previously undeveloped design connecting two major energy technologies and promises a general approach for storing solar energy electrochemically with high theoretical storage capacity and efficiency.

Researches on regenerative medicine-current state

Directory of Open Access Journals (Sweden)

WANG Zheng-guo

2012-11-01

Full Text Available 【Abstract】 Since 1980s, the rapid development of tissue engineering and stem cell research has pushed re-generative medicine to a new fastigium, and regenerative medicine has become a noticeable research field in the international biology and medicine. In China, about 100 million patients need repair and regeneration treatment every year, while the number is much larger in the world. Regenerative medicine could provide effective salvation for these patients. Both Chinese Academy of Sciences and Chinese Academy of Engineering have made roadmaps of 2010-2050 and 2011-2030 for regenerative medicine. The final goal of the two roadmaps is to make China go up to leading position in most research aspects of regenerative medicine. In accord with this strategy, the government and some enterprises have invested 3-5 billion RMB (0.5-0.8 billion USD for the research on regenerative medicine. In order to push the translation of regenerative medicine forward—from bench to bedside, a strategic alliance has been established, and it includes 27 top-level research institutes, medical institutes, colleges, universities and enterprises in the field of stem cell and regeneration medicine. Recently the journal, Science, has published a special issue—Regenerative Medi-cine in China, consisting of 35 papers dealing with stem cell and regeneration, tissue engineering and regeneration, trauma and regeneration and bases for tissue repair and regenerative medicine. It is predicated that a greater breakthrough in theory and practice of regenerative medicine will be achieved in the near future (20 to 30 years. Key words: Regenerative medicine; Tissue engineering; Stem cells; Wound healing

Regenerative energies - the environmentally friendly solution. Seminar volume. Pt. 2

International Nuclear Information System (INIS)

Haury, H.J.; Assmann, G.; Froese, B.; Jahn, T.

1995-01-01

The Information Environment organised its 16th journalists seminar on 9th March 1995 in Hamburg. In the second part of the seminar competent scientist gave an overview to the following questions: 1. Renewable energy as an solution from the dead end street? 2. What part of the energy demand could be covered by regenerative energy sources at all? 3. Ecology contra economy? 4. Inexhaustible energy source sun? 5. When do we start to import solar energy from the desert? 6. Move into the energy autarkic solar house in the year 2000? 7. Wind power plant park Germany? 8. Geothermal - component of the energy-mix 2005. The present volume contains the lectures which were given on these subjects. (orig./UA) [de

Integrated Photoelectrochemical Solar Energy Conversion and Organic Redox Flow Battery Devices.

Science.gov (United States)

Li, Wenjie; Fu, Hui-Chun; Li, Linsen; Cabán-Acevedo, Miguel; He, Jr-Hau; Jin, Song

2016-10-10

Building on regenerative photoelectrochemical solar cells and emerging electrochemical redox flow batteries (RFBs), more efficient, scalable, compact, and cost-effective hybrid energy conversion and storage devices could be realized. An integrated photoelectrochemical solar energy conversion and electrochemical storage device is developed by integrating regenerative silicon solar cells and 9,10-anthraquinone-2,7-disulfonic acid (AQDS)/1,2-benzoquinone-3,5-disulfonic acid (BQDS) RFBs. The device can be directly charged by solar light without external bias, and discharged like normal RFBs with an energy storage density of 1.15 Wh L -1 and a solar-to-output electricity efficiency (SOEE) of 1.7 % over many cycles. The concept exploits a previously undeveloped design connecting two major energy technologies and promises a general approach for storing solar energy electrochemically with high theoretical storage capacity and efficiency. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Practical Efficiency of Photovoltaic Panel Used for Solar Vehicles

Science.gov (United States)

Koyuncu, T.

2017-08-01

In this experimental investigation, practical efficiency of semi-flexible monocrystalline silicon solar panel used for a solar powered car called “Firat Force” and a solar powered minibus called “Commagene” was determined. Firat Force has 6 solar PV modules, a maintenance free long life gel battery pack, a regenerative brushless DC electric motor and Commagene has 12 solar PV modules, a maintenance free long life gel battery pack, a regenerative brushless DC electric motor. In addition, both solar vehicles have MPPT (Maximum power point tracker), ECU (Electronic control unit), differential, instrument panel, steering system, brake system, brake and gas pedals, mechanical equipments, chassis and frame. These two solar vehicles were used for people transportation in Adiyaman city, Turkey, during one year (June 2010-May 2011) of test. As a result, the practical efficiency of semi-flexible monocrystalline silicon solar panel used for Firat Force and Commagene was determined as 13 % in despite of efficiency value of 18% (at 1000 W/m2 and 25 °C ) given by the producer company. Besides, the total efficiency (from PV panels to vehicle wheel) of the system was also defined as 9%.

Regenerative similariton laser

Directory of Open Access Journals (Sweden)

Thibault North

2016-05-01

Full Text Available Self-pulsating lasers based on cascaded reshaping and reamplification (2R are capable of initiating ultrashort pulses despite the accumulation of large amounts of nonlinearities in all-fiber resonators. The spectral properties of pulses in self-similar propagation are compatible with cascaded 2R regeneration by offset filtering, making parabolic pulses suitable for the design of a laser of this recently introduced class. A new type of regenerative laser giving birth to similaritons is numerically investigated and shows that this laser is the analog of regenerative sources based solely on self-phase modulation and offset filtering. The regenerative similariton laser does not suffer from instabilities due to excessive nonlinearities and enables ultrashort pulse generation in a simple cavity configuration.

Setting a good example: Regenerative energies play an important role in Schleswig-Holstein

International Nuclear Information System (INIS)

Rave, K.

1995-01-01

In Schleswig-Holstein the use of regenerative energies is supported more than in any other Land of Germany. Due to the fact that large regions of the Land are situated in strong breeze zones, wind power plays the most important role. Almost 50% of the overall German wind current is gained in Schleswig-Holstein. Furthermore solar energy and water power are also used directly. (orig.) [de

Regenerative rehabilitation: a new future?

Science.gov (United States)

Perez-Terzic, Carmen; Childers, Martin K

2014-11-01

Modern rehabilitation medicine is propelled by newfound knowledge aimed at offering solutions for an increasingly aging population afflicted by chronic debilitating conditions. Considered a core component of future health care, the rollout of regenerative medicine underscores a paradigm shift in patient management targeted at restoring physiologic function and restituting normative impact. Nascent regenerative technologies offer unprecedented prospects in achieving repair of degenerated, diseased, or damaged tissues. In this context, principles of regenerative science are increasingly integrated in rehabilitation practices as illustrated in the present Supplement. Encompassing a growing multidisciplinary domain, the emergent era of "regenerative rehabilitation" brings radical innovations at the forefront of healthcare blueprints.

The pharmacology of regenerative medicine.

Science.gov (United States)

Christ, George J; Saul, Justin M; Furth, Mark E; Andersson, Karl-Erik

2013-07-01

Regenerative medicine is a rapidly evolving multidisciplinary, translational research enterprise whose explicit purpose is to advance technologies for the repair and replacement of damaged cells, tissues, and organs. Scientific progress in the field has been steady and expectations for its robust clinical application continue to rise. The major thesis of this review is that the pharmacological sciences will contribute critically to the accelerated translational progress and clinical utility of regenerative medicine technologies. In 2007, we coined the phrase "regenerative pharmacology" to describe the enormous possibilities that could occur at the interface between pharmacology, regenerative medicine, and tissue engineering. The operational definition of regenerative pharmacology is "the application of pharmacological sciences to accelerate, optimize, and characterize (either in vitro or in vivo) the development, maturation, and function of bioengineered and regenerating tissues." As such, regenerative pharmacology seeks to cure disease through restoration of tissue/organ function. This strategy is distinct from standard pharmacotherapy, which is often limited to the amelioration of symptoms. Our goal here is to get pharmacologists more involved in this field of research by exposing them to the tools, opportunities, challenges, and interdisciplinary expertise that will be required to ensure awareness and galvanize involvement. To this end, we illustrate ways in which the pharmacological sciences can drive future innovations in regenerative medicine and tissue engineering and thus help to revolutionize the discovery of curative therapeutics. Hopefully, the broad foundational knowledge provided herein will spark sustained conversations among experts in diverse fields of scientific research to the benefit of all.

Integrated Photoelectrochemical Solar Energy Conversion and Organic Redox Flow Battery Devices

KAUST Repository

Li, Wenjie; Fu, Hui-chun; Li, Linsen; Cabá n-Acevedo, Miguel; He, Jr-Hau; Jin, Song

2016-01-01

photoelectrochemical solar energy conversion and electrochemical storage device is developed by integrating regenerative silicon solar cells and 9,10-anthraquinone-2,7-disulfonic acid (AQDS)/1,2-benzoquinone-3,5-disulfonic acid (BQDS) RFBs. The device can be directly

Solar Power Augmented Electrolysis Module for Energy Storage

Data.gov (United States)

National Aeronautics and Space Administration — Integrating solar photovoltaic power with regenerative fuel cell systems for energy storage can often be very complex and costly. It usually requires complex power...

REGEN: Ancestral Genome Reconstruction for Bacteria.

Science.gov (United States)

Yang, Kuan; Heath, Lenwood S; Setubal, João C

2012-07-18

Ancestral genome reconstruction can be understood as a phylogenetic study with more details than a traditional phylogenetic tree reconstruction. We present a new computational system called REGEN for ancestral bacterial genome reconstruction at both the gene and replicon levels. REGEN reconstructs gene content, contiguous gene runs, and replicon structure for each ancestral genome. Along each branch of the phylogenetic tree, REGEN infers evolutionary events, including gene creation and deletion and replicon fission and fusion. The reconstruction can be performed by either a maximum parsimony or a maximum likelihood method. Gene content reconstruction is based on the concept of neighboring gene pairs. REGEN was designed to be used with any set of genomes that are sufficiently related, which will usually be the case for bacteria within the same taxonomic order. We evaluated REGEN using simulated genomes and genomes in the Rhizobiales order.

REGEN: Ancestral Genome Reconstruction for Bacteria

Directory of Open Access Journals (Sweden)

João C. Setubal

2012-07-01

Full Text Available Ancestral genome reconstruction can be understood as a phylogenetic study with more details than a traditional phylogenetic tree reconstruction. We present a new computational system called REGEN for ancestral bacterial genome reconstruction at both the gene and replicon levels. REGEN reconstructs gene content, contiguous gene runs, and replicon structure for each ancestral genome. Along each branch of the phylogenetic tree, REGEN infers evolutionary events, including gene creation and deletion and replicon fission and fusion. The reconstruction can be performed by either a maximum parsimony or a maximum likelihood method. Gene content reconstruction is based on the concept of neighboring gene pairs. REGEN was designed to be used with any set of genomes that are sufficiently related, which will usually be the case for bacteria within the same taxonomic order. We evaluated REGEN using simulated genomes and genomes in the Rhizobiales order.

Changes in Regenerative Capacity through Lifespan

Directory of Open Access Journals (Sweden)

Maximina H. Yun

2015-10-01

Full Text Available Most organisms experience changes in regenerative abilities through their lifespan. During aging, numerous tissues exhibit a progressive decline in homeostasis and regeneration that results in tissue degeneration, malfunction and pathology. The mechanisms responsible for this decay are both cell intrinsic, such as cellular senescence, as well as cell-extrinsic, such as changes in the regenerative environment. Understanding how these mechanisms impact on regenerative processes is essential to devise therapeutic approaches to improve tissue regeneration and extend healthspan. This review offers an overview of how regenerative abilities change through lifespan in various organisms, the factors that underlie such changes and the avenues for therapeutic intervention. It focuses on established models of mammalian regeneration as well as on models in which regenerative abilities do not decline with age, as these can deliver valuable insights for our understanding of the interplay between regeneration and aging.

Regenerative Rehabilitation – a New Future?

Science.gov (United States)

Perez-Terzic, Carmen; Childers, Martin K.

2014-01-01

Modern rehabilitation medicine is propelled by newfound knowledge aimed at offering solutions for an increasingly aging population afflicted by chronic debilitating conditions. Considered a core component of future healthcare, the roll-out of regenerative medicine underscores a paradigm shift in patient management targeted at restoring physiologic function and restituting normative impact. Nascent regenerative technologies offer unprecedented prospects in achieving repair of degenerated, diseased or damaged tissues. In this context, principles of regenerative science are increasingly integrated in rehabilitation practices as illustrated in the present Supplement. Encompassing a growing multidisciplinary domain, the emergent era of “regenerative rehabilitation” brings radical innovations at the forefront of healthcare blueprints. PMID:25310603

REGEN: Ancestral Genome Reconstruction for Bacteria

OpenAIRE

Yang, Kuan; Heath, Lenwood S.; Setubal, João C.

2012-01-01

Ancestral genome reconstruction can be understood as a phylogenetic study with more details than a traditional phylogenetic tree reconstruction. We present a new computational system called REGEN for ancestral bacterial genome reconstruction at both the gene and replicon levels. REGEN reconstructs gene content, contiguous gene runs, and replicon structure for each ancestral genome. Along each branch of the phylogenetic tree, REGEN infers evolutionary events, including gene creation and deleti...

Regenerative Therapy for Retinal Disorders

Directory of Open Access Journals (Sweden)

Narsis Daftarian

2010-01-01

Full Text Available Major advances in various disciplines of basic sciences including embryology, molecular and cell biology, genetics, and nanotechnology, as well as stem cell biology have opened new horizons for regenerative therapy. The unique characteristics of stem cells prompt a sound understanding for their use in modern regenerative therapies. This review article discusses stem cells, developmental stages of the eye field, eye field transcriptional factors, and endogenous and exogenous sources of stem cells. Recent studies and challenges in the application of stem cells for retinal pigment epithelial degeneration models will be summarized followed by obstacles facing regenerative therapy.

Researches on regenerative medicine-current state and prospect.

Science.gov (United States)

Wang, Zheng-Guo; Xiao, Kai

2012-01-01

Since 1980s, the rapid development of tissue engineering and stem cell research has pushed regenerative medicine to a new fastigium, and regenerative medicine has become a noticeable research field in the international biology and medicine. In China, about 100 million patients need repair and regeneration treatment every year, while the number is much larger in the world. Regenerative medicine could provide effective salvation for these patients. Both Chinese Academy of Sciences and Chinese Academy of Engineering have made roadmaps of 2010-2050 and 2011-2030 for regenerative medicine. The final goal of the two roadmaps is to make China go up to leading position in most research aspects of regenerative medicine. In accord with this strategy, the government and some enterprises have invested 3-5 billion RMB (0.5-0.8 billion USD) for the research on regenerative medicine. In order to push the translation of regenerative medicine forward-from bench to bedside, a strategic alliance has been established, and it includes 27 top-level research institutes, medical institutes, colleges, universities and enterprises in the field of stem cell and regeneration medicine. Recently the journal, Science, has published a special issue-Regenerative Medicine in China, consisting of 35 papers dealing with stem cell and regeneration, tissue engineering and regeneration, trauma and regeneration and bases for tissue repair and regenerative medicine. It is predicated that a greater breakthrough in theory and practice of regenerative medicine will be achieved in the near future (20 to 30 years).

An adaptive dual-optimal path-planning technique for unmanned air vehicles with application to solar-regenerative high altitude long endurance flight

Science.gov (United States)

Whitfield, Clifford A.

2009-12-01

A multi-objective technique for Unmanned Air Vehicle (UAV) path and trajectory autonomy generation, through task allocation and sensor fusion has been developed. The Dual-Optimal Path-Planning (D-O.P-P.) Technique generates on-line adaptive flight paths for UAVs based on available flight windows and environmental influenced objectives. The environmental influenced optimal condition, known as the driver' determines the condition, within a downstream virtual window of possible vehicle destinations and orientation built from the UAV kinematics. The intermittent results are pursued by a dynamic optimization technique to determine the flight path. This sequential optimization technique is a multi-objective optimization procedure consisting of two goals, without requiring additional information to combine the conflicting objectives into a single-objective. An example case-study and additional applications are developed and the results are discussed; including the application to the field of Solar Regenerative (SR) High Altitude Long Endurance (HALE) UAV flight. Harnessing solar energy has recently been adapted for use on high altitude UAV platforms. An aircraft that uses solar panels and powered by the sun during the day and through the night by SR systems, in principle could sustain flight for weeks or months. The requirements and limitations of solar powered flight were determined. The SR-HALE UAV platform geometry and flight characteristics were selected from an existing aircraft that has demonstrated the capability for sustained flight through flight tests. The goals were to maintain continual Situational Awareness (SA) over a case-study selected Area of Interest (AOI) and existing UAV power and surveillance systems. This was done for still wind and constant wind conditions at altitude along with variations in latitude. The characteristics of solar flux and the dependence on the surface location and orientation were established along with fixed flight maneuvers for

Solar heating for a village; Ein Dorf heizt solar

Energy Technology Data Exchange (ETDEWEB)

Roepcke, Ina

2013-07-05

In Buesingen (administrative district of Konstanz) a solar thermal system with 1091 sqm collector area is put into operation. Together with two wood chip boilers they supply more than 100 private and municipal buildings with regenerative heat. [German] In Buesingen im Landkreis Konstanz ist eine solarthermische Anlage mit 1091 qm Kollektorflaeche in Betrieb gegangen. Zusammen mit zwei Hackschnitzelkesseln versorgt sie ueber 100 private und kommunale Gebaeude mit regenerativer Waerme.

Summary of: Regenerative endodontics.

Science.gov (United States)

Clark, Stephen J

2014-03-01

Significant advances in our understanding of the biological processes involved in tooth development and repair at the cellular and molecular levels have underpinned the newly emerging area of regenerative endodontics. Development of treatment protocols based on exploiting the natural wound healing properties of the dental pulp and applying tissue engineering principles has allowed reporting of case series showing preservation of tissue vitality and apexogenesis. To review current case series reporting regenerative endodontics. Current treatment approaches tend to stimulate more reparative than regenerative responses in respect of the new tissue generated, which often does not closely resemble the physiological structure of dentine-pulp. However, despite these biological limitations, such techniques appear to offer significant promise for improved treatment outcomes. Improved biological outcomes will likely emerge from the many experimental studies being reported and will further contribute to improvements in clinical treatment protocols.

A review of the regenerative endodontic treatment procedure

Directory of Open Access Journals (Sweden)

Bin-Na Lee,

2015-08-01

Full Text Available Traditionally, apexification has been used to treat immature permanent teeth that have lost pulp vitality. This technique promotes the formation of an apical barrier to close the open apex so that the filling materials can be confined to the root canal. Because tissue regeneration cannot be achieved with apexification, a new technique called regenerative endodontic treatment was presented recently to treat immature permanent teeth. Regenerative endodontic treatment is a treatment procedure designed to replace damaged pulp tissue with viable tissue which restores the normal function of the pulp-dentin structure. After regenerative endodontic treatment, continued root development and hard tissue deposition on the dentinal wall can occur under ideal circumstances. However, it is difficult to predict the result of regenerative endodontic treatment. Therefore, the purpose of this study was to summarize multiple factors effects on the result of regenerative endodontic treatment in order to achieve more predictable results. In this study, we investigated the features of regenerative endodontic treatment in comparison with those of other pulp treatment procedures and analyzed the factors that have an effect on regenerative endodontic treatment.

Regenerative endodontics: a comprehensive review.

Science.gov (United States)

Kim, S G; Malek, M; Sigurdsson, A; Lin, L M; Kahler, B

2018-05-19

The European Society of Endodontology and the American Association for Endodontists have released position statements and clinical considerations for regenerative endodontics. There is increasing literature on this field since the initial reports of Iwaya et al. (Dental Traumatology, 17, 2001, 185) and Banchs & Trope (Journal of Endodontics, 30, 2004, 196). Endogenous stem cells from an induced periapical bleeding and scaffolds using blood clot, platelet rich plasma or platelet-rich fibrin have been utilized in regenerative endodontics. This approach has been described as a 'paradigm shift' and considered the first treatment option for immature teeth with pulp necrosis. There are three treatment outcomes of regenerative endodontics; (i) resolution of clinical signs and symptoms; (ii) further root maturation; and (iii) return of neurogenesis. It is known that results are variable for these objectives, and true regeneration of the pulp/dentine complex is not achieved. Repair derived primarily from the periodontal and osseous tissues has been shown histologically. It is hoped that with the concept of tissue engineering, namely stem cells, scaffolds and signalling molecules, that true pulp regeneration is an achievable goal. This review discusses current knowledge as well as future directions for regenerative endodontics. Patient-centred outcomes such as tooth discolouration and possibly more appointments with the potential for adverse effects needs to be discussed with patients and parents. Based on the classification of Cvek (Endodontics and Dental Traumatology, 8, 1992, 45), it is proposed that regenerative endodontics should be considered for teeth with incomplete root formation although teeth with near or complete root formation may be more suited for conventional endodontic therapy or MTA barrier techniques. However, much is still not known about clinical and biological aspects of regenerative endodontics. © 2018 International Endodontic Journal. Published by

Regenerative-filter-incinerator device

Energy Technology Data Exchange (ETDEWEB)

Rosebrock, T.L.

1977-10-18

A regenerative-filter-incinerator device, for use in the exhaust system of a diesel engine, includes a drum-like regenerative-heat exchanger-filter assembly rotatably mounted within a housing that is adapted to be installed directly in the exhaust gas stream discharged from a diesel engine as close to the engine as possible. The regenerative-heat exchanger-filter assembly provides an inner chamber which serves as a reaction chamber for the secondary combustion of exhaust gases including particulates discharged from the engine. The regenerative-heat exchanger-filter assembly includes separately rotatable heat exchange-filter elements pervious to radial flow of fluid therethrough and adapted to filter out particulates from the exhaust gases and to carry them into the reaction chamber. During engine operation, the reaction chamber is provided with a quantity of heat, as necessary, to effect secondary combustion of the exhaust gases and particulates by means of an auxiliary heat source and the heat generated within the reaction chamber is stored in the individual heat exchange-filter elements during the discharge of exhaust gases therethrough from the reaction chamber and this heat is then transferred to the inflowing volume of the exhaust gases so that, in effect, exhaust gas is discharged from the device at substantially the same temperature as it was during its inlet into the device from the engine.

Regenerative braking system of PM synchronous motor

Science.gov (United States)

Gao, Qian; Lv, Chengxing; Zhao, Na; Zang, Hechao; Jiang, Huilue; Zhang, Zhaowen; Zhang, Fengli

2018-04-01

Permanent-magnet synchronous motor is widely adopted in many fields with the advantage of a high efficiency and a high torque density. Regenerative Braking Systems (RBS) provide an efficient method to assist PMSM system achieve better fuel economy and lowering exhaust emissions. This paper describes the design and testing of the regenerative braking systems of PMSM. The mode of PWM duty has been adjusted to control regenerative braking of PMSM using energy controller for the port-controlled Hamiltonian model. The simulation analysis indicates that a smooth control could be realized and the highest efficiency and the smallest current ripple could be achieved by Regenerative Braking Systems.

Regenerative Perspective in Modern Dentistry

Directory of Open Access Journals (Sweden)

Mihnea Ioan Nicolescu

2016-04-01

Full Text Available This review aims to trace the contour lines of regenerative dentistry, to offer an introductory overview on this emerging field to both dental students and practitioners. The crystallized depiction of the concept is a translational approach, connecting dental academics to scientific research and clinical utility. Therefore, this review begins by presenting the general features of regenerative medicine, and then gradually introduces the specific aspects of major dental subdomains, highlighting the progress achieved during the last years by scientific research and, in some cases, which has already been translated into clinical results. The distinct characteristics of stem cells and their microenvironment, together with their diversity in the oral cavity, are put into the context of research and clinical use. Examples of regenerative studies regarding endodontic and periodontal compartments, as well as hard (alveolar bone and soft (salivary glands related tissues, are presented to make the reader further acquainted with the topic. Instead of providing a conclusion, we will emphasize the importance for all dental community members, from young students to experienced dentists, of an early awareness rising regarding biomedical research progress in general and regenerative dentistry in particular.

Current overview on challenges in regenerative endodontics

Science.gov (United States)

Bansal, Ramta; Jain, Aditya; Mittal, Sunandan

2015-01-01

Introduction: Regenerative endodontics provides hope of converting the non-vital tooth into vital once again. It focuses on substituting traumatized and pathological pulp with functional pulp tissue. Current regenerative procedures successfully produce root development but still fail to re-establish real pulp tissue and give unpredictable results. There are several drawbacks that need to be addressed to improve the quality and efficiency of the treatment. Aim: The aim of this review article is to discuss major priorities that ought to be dealt before applications of regenerative endodontics flourish the clinical practice. Materials and Methods: A web-based research on MEDLINE was done using filter terms Review, published in the last 10 years and Dental journals. Keywords used for research were “regenerative endodontics,” “dental stem cells,” “growth factor regeneration,” “scaffolds,” and “challenges in regeneration.” This review article screened about 150 articles and then the relevant information was compiled. Results: Inspite of the impressive growth in regenerative endodontic field, there are certain loopholes in the existing treatment protocols that might sometimes result in undesired and unpredictable outcomes. Conclusion: Considerable research and development efforts are required to improve and update existing regenerative endodontic strategies to make it an effective, safe, and biological mode to save teeth. PMID:25657518

Cell and biomolecule delivery for regenerative medicine

Science.gov (United States)

Smith, Ian O; Ma, Peter X

2010-01-01

Regenerative medicine is an exciting field that aims to create regenerative alternatives to harvest tissues for transplantation. In this approach, the delivery of cells and biological molecules plays a central role. The scaffold (synthetic temporary extracellular matrix) delivers cells to the regenerative site and provides three-dimensional environments for the cells. To fulfil these functions, we design biodegradable polymer scaffolds with structural features on multiple size scales. To enhance positive cell–material interactions, we design nano-sized structural features in the scaffolds to mimic the natural extracellular matrix. We also integrate micro-sized pore networks to facilitate mass transport and neo tissue regeneration. We also design novel polymer devices and self-assembled nanospheres for biomolecule delivery to recapitulate key events in developmental and wound healing processes. Herein, we present recent work in biomedical polymer synthesis, novel processing techniques, surface engineering and biologic delivery. Examples of enhanced cellular/tissue function and regenerative outcomes of these approaches are discussed to demonstrate the excitement of the biomimetic scaffold design and biologic delivery in regenerative medicine. PMID:27877317

Comparative energy analysis on a new regenerative Brayton cycle

International Nuclear Information System (INIS)

Goodarzi, M.

2016-01-01

Highlights: • New regenerative Brayton cycle has been introduced. • New cycle has higher thermal efficiency and lower exhausted heat per output power. • Regenerator may remain useful in the new cycle even at high pressure ratio. • New regenerative Brayton cycle is suggested for low pressure ratio operations. - Abstract: Gas turbines are frequently used for power generation. Brayton cycle is the basis for gas turbine operation and developing the alternative cycles. Regenerative Brayton cycle is a developed cycle for basic Brayton cycle with higher thermal efficiency at low to moderate pressure ratios. A new regenerative Brayton cycle has been introduced in the present study. Energy analysis has been conducted on ideal cycles to compare them from the first law of thermodynamics viewpoint. Comparative analyses showed that the new regenerative Brayton cycle has higher thermal efficiency than the original one at the same pressure ratio, and also lower heat absorption and exhausted heat per unite output power. Computed results show that new cycle improves thermal efficiency from 12% to 26% relative to the original regenerative Brayton cycle in the range of studied pressure ratios. Contrary to the original regenerative Brayton cycle, regenerator remains useful in the new regenerative Brayton cycle even at higher pressure ratio.

Microscale Regenerative Heat Exchanger

Science.gov (United States)

Moran, Matthew E.; Stelter, Stephan; Stelter, Manfred

2006-01-01

The device described herein is designed primarily for use as a regenerative heat exchanger in a miniature Stirling engine or Stirling-cycle heat pump. A regenerative heat exchanger (sometimes called, simply, a "regenerator" in the Stirling-engine art) is basically a thermal capacitor: Its role in the Stirling cycle is to alternately accept heat from, then deliver heat to, an oscillating flow of a working fluid between compression and expansion volumes, without introducing an excessive pressure drop. These volumes are at different temperatures, and conduction of heat between these volumes is undesirable because it reduces the energy-conversion efficiency of the Stirling cycle.

Regenerative Braking System for Series Hybrid Electric City Bus

OpenAIRE

Zhang, Junzhi; Lu, Xin; Xue, Junliang; Li, Bos

2008-01-01

Regenerative Braking Systems (RBS) provide an efficient method to assist hybrid electric buses achieve better fuel economy while lowering exhaust emissions. This paper describes the design and testing of three regenerative braking systems, one of which is a series regenerative braking system and two of which are parallel regenerative braking systems. The existing friction based Adjustable Braking System (ABS) on the bus is integrated with each of the new braking systems in order to ensure bus...

Structural and optical characterization of electrodeposited CdSe in mesoporous anatase TiO2 for regenerative quantum-dot-sensitized solar cells

International Nuclear Information System (INIS)

Sauvage, Frédéric; Davoisne, Carine; Philippe, Laetitia; Elias, Jamil

2012-01-01

We investigated CdSe-sensitized TiO 2 solar cells by means of electrodeposition under galvanostatic control. The electrodeposition of CdSe within the mesoporous film of TiO 2 gives rise to a uniform, thickness controlled, conformal layer of nanostructured CdSe particles intimately wrapping the anatase TiO 2 nanoparticles. This technique has the advantage of providing not only a fast method for sensitization ( 2 –CdSe core–shell structure followed by the growth of an assembly of CdSe nanoparticles resembling cauliflowers. This assembly exhibits at its core a mosaic texture with crystallites of about 3 nm in size, in contrast to a shell composed of well-crystallized single crystals between 5 and 10 nm in size. Preliminary results on the photovoltaic performance of such a nanostructured composite of TiO 2 and CdSe show 0.8% power conversion efficiency under A.M.1.5 G conditions—100 mW cm −2 in association with a new regenerative redox couple based on cobalt(+III/+II) polypyridil complex (V oc = 485 mV, J sc = 4.26 mA cm −2 , ff=0.37). (paper)

The regenerative medicine coalition. Interview with Frank-Roman Lauter.

Science.gov (United States)

Lauter, Frank-Roman

2012-11-01

Frank-Roman Lauter, Secretary General of the recently launched Regenerative Medicine Coalition, explains how the coalition was formed and what they hope to achieve. Frank-Roman Lauter has served as Secretary General of the Regenerative Medicine Coalition since 2012, and as Head of Business Development at Berlin-Brandenburg Center for Regenerative Therapies since 2007. Frank-Roman Lauter's interest is the organization of academic infrastructures to promote efficient translation of research findings into new therapies. He co-organizes joined strategy development for regenerative medicine clusters from seven European countries (FP7-EU Project) and has initiated cooperation between the California Institute for Regenerative Medicine and the German Federal Ministry for Education & Research, resulting in a joined funding program. Recently, he cofounded the international consortium of Regenerative Medicine translational centers (RMC; www.the-rmc.org ). Trained as a molecular biologist at the Max-Planck Institute in Berlin-Dahlem and at Stanford, he has 16 years of experience as an entrepreneur and life science manager in Germany and the USA.

Regenerative Endodontics: Barriers and Strategies for Clinical Translation

OpenAIRE

Kim, Sahng G.; Zhou, Jian; Ye, Ling; Cho, Shoko; Suzuki, Takahiro; Fu, Susan Y.; Yang, Rujing; Zhou, Xuedong; Mao, Jeremy J.

2012-01-01

Despite a great deal of enthusiasm and effort, regenerative endodontics has encountered substantial challenges towards clinical translation. Recent adoption by the American Dental Association (ADA) of evoked pulp bleeding in immature permanent teeth is an important step for regenerative endodontics. However, there is no regenerative therapy for the majority of endodontic diseases. Simple recapitulation of cell therapy and tissue engineering strategies that are under development for other orga...

The TMI Regenerative Solid Oxide Fuel Cell

Science.gov (United States)

Cable, Thomas L.; Ruhl, Robert C.; Petrik, Michael

1996-01-01

Energy storage and production in space requires rugged, reliable hardware which minimizes weight, volume, and maintenance while maximizing power output and usable energy storage. Systems generally consist of photovoltaic solar arrays which operate (during sunlight cycles) to provide system power and regenerate fuel (hydrogen) via water electrolysis and (during dark cycles) fuel cells convert hydrogen into electricity. Common configurations use two separate systems (fuel cell and electrolyzer) in conjunction with photovoltaic cells. Reliability, power to weight and power to volume ratios could be greatly improved if both power production (fuel cells) and power storage (electrolysis) functions can be integrated into a single unit. The solid oxide fuel cell (SOFC) based design integrates fuel cell and electrolyzer functions and potentially simplifies system requirements. The integrated fuel cell/electrolyzer design also utilizes innovative gas storage concepts and operates like a rechargeable 'hydrogen-oxygen battery'. Preliminary research has been completed on improved H2/H20 electrode (SOFC anode/electrolyzer cathode) materials for regenerative fuel cells. Tests have shown improved cell performance in both fuel and electrolysis modes in reversible fuel cell tests. Regenerative fuel cell efficiencies, ratio of power out (fuel cell mode) to power in (electrolyzer mode), improved from 50 percent using conventional electrode materials to over 80 percent. The new materials will allow a single SOFC system to operate as both the electolyzer and fuel cell. Preliminary system designs have also been developed to show the technical feasibility of using the design for space applications requiring high energy storage efficiencies and high specific energy. Small space systems also have potential for dual-use, terrestrial applications.

Regenerative medicine applications in combat casualty care.

Science.gov (United States)

Fleming, Mark E; Bharmal, Husain; Valerio, Ian

2014-03-01

The purpose of this report is to describe regenerative medicine applications in the management of complex injuries sustained by service members injured in support of the wars in Afghanistan and Iraq. Improvements in body armor, resuscitative techniques and faster transport have translated into increased patient survivability and more complex wounds. Combat-related blast injuries have resulted in multiple extremity injuries, significant tissue loss and amputations. Due to the limited availability and morbidity associated with autologous tissue donor sites, the introduction of regenerative medicine has been critical in managing war extremity injuries with composite massive tissue loss. Through case reports and clinical images, this report reviews the application of regenerative medicine modalities employed to manage combat-related injuries. It illustrates that the novel use of hybrid reconstructions combining traditional and regenerative medicine approaches are an effective tool in managing wounds. Lessons learned can be adapted to civilian care.

Design of An Energy Efficient Hydraulic Regenerative circuit

Science.gov (United States)

Ramesh, S.; Ashok, S. Denis; Nagaraj, Shanmukha; Adithyakumar, C. R.; Reddy, M. Lohith Kumar; Naulakha, Niranjan Kumar

2018-02-01

Increasing cost and power demand, leads to evaluation of new method to increase through productivity and help to solve the power demands. Many researchers have break through to increase the efficiency of a hydraulic power pack, one of the promising methods is the concept of regenerative. The objective of this research work is to increase the efficiency of a hydraulic circuit by introducing a concept of regenerative circuit. A Regenerative circuit is a system that is used to speed up the extension stroke of the double acting single rod hydraulic cylinder. The output is connected to the input in the directional control value. By this concept, increase in velocity of the piston and decrease the cycle time. For the research, a basic hydraulic circuit and a regenerative circuit are designated and compared both with their results. The analysis was based on their time taken for extension and retraction of the piston. From the detailed analysis of both the hydraulic circuits, it is found that the efficiency by introducing hydraulic regenerative circuit increased by is 5.3%. The obtained results conclude that, implementing hydraulic regenerative circuit in a hydraulic power pack decreases power consumption, reduces cycle time and increases productivity in a longer run.

Thermodynamic performance assessment of an integrated geothermal powered supercritical regenerative organic Rankine cycle and parabolic trough solar collectors

International Nuclear Information System (INIS)

Cakici, Duygu Melek; Erdogan, Anil; Colpan, Can Ozgur

2017-01-01

In this study, the thermodynamic performance of an integrated geothermal powered supercritical regenerative organic Rankine cycle (ORC) and parabolic trough solar collectors (PTSC) is assessed. A thermal model based on the principles of thermodynamics (mass, energy, and exergy balances) and heat transfer is first developed for the components of this integrated system. This model gives the performance assessment parameters of the system such as the electrical and exergetic efficiencies, total exergy destruction and loss, productivity lack, fuel depletion ratio, and improvement potential rate. To validate this model, the data of an existing geothermal power plant based on a supercritical ORC and literature data for the PTSC are used. After validation, parametric studies are conducted to assess the effect of some of the important design and operating parameters on the performance of the system. As a result of these studies, it is found that the integration of ORC and PTSC systems increases the net power output but decreases the electrical and exergetic efficiencies of the integrated system. It is also shown that R134a is the most suitable working fluid type for this system; and the PTSCs and air cooled condenser are the main sources of the exergy destructions. - Highlights: • A geothermal power plant integrated with PTSC is investigated. • Different approaches for defining the exergetic efficiency are used. • The PTSCs and ACC are the main sources of the exergy destructions. • R134a gives the highest performance for any number of collectors studied.

Aarhus Regenerative Orthopaedics Symposium (AROS)

DEFF Research Database (Denmark)

Foldager, Casper B.; Bendtsen, Michael; Berg, Lise C.

2016-01-01

to musculoskeletal pain and disability. The Aarhus Regenerative Orthopaedics Symposium (AROS) 2015 was motivated by the need to address regenerative challenges in an ageing population by engaging clinicians, basic scientists, and engineers. In this position paper, we review our contemporary understanding of societal......, patient-related, and basic science-related challenges in order to provide a reasoned roadmap for the future to deal with this compelling and urgent healthcare problem. © 2017 The Author(s). Published by Taylor & Francis on behalf of the Nordic Orthopedic Federation....

Solar-Powered, Liquid-Desiccant Air Conditioner for Low-Electricity Humidity Control

Science.gov (United States)

2012-11-01

reading Current transformer Regen and conditioner Continental Controls CTS-0750-30 1 % of reading Pyranometer Horizontal Campbell...indoor comfort conditions. A pyranometer was used to quantify the efficiency of the solar collector array. Two measurements of electric energy were

A survey of dental residents' expectations for regenerative endodontics.

Science.gov (United States)

Manguno, Christine; Murray, Peter E; Howard, Cameron; Madras, Jonathan; Mangan, Stephen; Namerow, Kenneth N

2012-02-01

The objective was to survey a group of dental residents regarding their expectations for using regenerative endodontic procedures as part of future dental treatments. After institutional review board approval, the opinions of 32 dentists who were having postgraduate residency training to become specialists in a dental school were surveyed. The survey had 40 questions about professional status, ethical beliefs, judgment, and clinical practice. It was found that 83.9% of dentists had no continuing education or training in stem cells or regenerative endodontic procedures. Results showed that 96.8% of dentists are willing to receive training to be able to provide regenerative endodontic procedures for their patients. Of the total group, 49.1% of dentists already use membranes, scaffolds, or bioactive materials to provide dental treatment. It was determined that 47.3% of dentists agree that the costs of regenerative procedures should be comparable with current treatments. It was also found that 55.1% of dentists were unsure whether regenerative procedures would be successful. Dentists are supportive of using regenerative endodontic procedures in their dental practice, and they are willing to undergo extra training and to buy new technology to provide new procedures. Nevertheless, dentists also need more evidence for the effectiveness and safety of regenerative treatments before they will be recommended for most patients. Copyright © 2012. Published by Elsevier Inc.

Platelet-rich fibrin: a boon in regenerative endodontics.

Science.gov (United States)

Rebentish, Priyanka D; Umashetty, Girish; Kaur, Harpreet; Doizode, Trupthi; Kaslekar, Mithun; Chowdhury, Shouvik

2016-12-01

Research into regenerative dentistry has contributed momentum to the field of molecular biology. Periapical surgery aims at removing periapical pathology to achieve complete wound healing and regeneration of bone and periodontal tissue. Regenerative endodontic procedures are widely being added to the current armamentarium of pulp therapy procedures. The regenerative potential of platelets has been deliberated. Platelet-rich fibrin (PRF) is a wonderful tissue-engineering product and has recently gained much popularity due its promising results in wound healing bone induction. The features of this product are an attribute of platelets which, after cellular interactions, release growth factors and have shown application in diverse disciplines of dentistry. This paper is intended to shed light onto the various prospects of PRF and to provide clinical insight into regenerative endodontic therapy.

Regenerative Rehabilitation: Combining Stem Cell Therapies and Activity-Dependent Stimulation.

Science.gov (United States)

Moritz, Chet T; Ambrosio, Fabrisia

2017-07-01

The number of clinical trials in regenerative medicine is burgeoning, and stem cell/tissue engineering technologies hold the possibility of becoming the standard of care for a multitude of diseases and injuries. Advances in regenerative biology reveal novel molecular and cellular targets, with potential to optimize tissue healing and functional recovery, thereby refining rehabilitation clinical practice. The purpose of this review is to (1) highlight the potential for synergy between the fields of regenerative medicine and rehabilitation, a convergence of disciplines known as regenerative rehabilitation; (2) provide translational examples of regenerative rehabilitation within the context of neuromuscular injuries and diseases; and (3) offer recommendations for ways to leverage activity dependence via combined therapy and technology, with the goal of enhancing long-term recovery. The potential clinical benefits of regenerative rehabilitation will likely become a critical aspect in the standard of care for many neurological and musculoskeletal disorders.

Analysis of regenerative thermal storage geometries for solar gas turbines

CSIR Research Space (South Africa)

Klein, P

2014-08-01

Full Text Available Ceramic heat regenerators are suited to providing thermal storage for concentrating solar power stations based on a recuperated gas turbine cycle. Randomly packed beds of spheres and saddles; honeycombs and checker bricks were identified...

Overcoming immunological barriers in regenerative medicine.

Science.gov (United States)

Zakrzewski, Johannes L; van den Brink, Marcel R M; Hubbell, Jeffrey A

2014-08-01

Regenerative therapies that use allogeneic cells are likely to encounter immunological barriers similar to those that occur with transplantation of solid organs and allogeneic hematopoietic stem cells (HSCs). Decades of experience in clinical transplantation hold valuable lessons for regenerative medicine, offering approaches for developing tolerance-induction treatments relevant to cell therapies. Outside the field of solid-organ and allogeneic HSC transplantation, new strategies are emerging for controlling the immune response, such as methods based on biomaterials or mimicry of antigen-specific peripheral tolerance. Novel biomaterials can alter the behavior of cells in tissue-engineered constructs and can blunt host immune responses to cells and biomaterial scaffolds. Approaches to suppress autoreactive immune cells may also be useful in regenerative medicine. The most innovative solutions will be developed through closer collaboration among stem cell biologists, transplantation immunologists and materials scientists.

Regenerative endodontics--Creating new horizons.

Science.gov (United States)

Dhillon, Harnoor; Kaushik, Mamta; Sharma, Roshni

2016-05-01

Trauma to the dental pulp, physical or microbiologic, can lead to inflammation of the pulp followed by necrosis. The current treatment modality for such cases is non-surgical root canal treatment. The damaged tissue is extirpated and the root canal system prepared. It is then obturated with an inert material such a gutta percha. In spite of advances in techniques and materials, 10%-15% of the cases may end in failure of treatment. Regenerative endodontics combines principles of endodontics, cell biology, and tissue engineering to provide an ideal treatment for inflamed and necrotic pulp. It utilizes mesenchymal stem cells, growth factors, and organ tissue culture to provide treatment. Potential treatment modalities include induction of blood clot for pulp revascularization, scaffold aided regeneration, and pulp implantation. Although in its infancy, successful treatment of damaged pulp tissue has been performed using principles of regenerative endodontics. This field is dynamic and exciting with the ability to shape the future of endodontics. This article highlights the fundamental concepts, protocol for treatment, and possible avenues for research in regenerative endodontics. © 2015 Wiley Periodicals, Inc.

The dissolution kinetics of magnetite under regenerative conditions

International Nuclear Information System (INIS)

Ranganathan, S.

2004-01-01

Dissolution studies of magnetite were carried out under regenerative conditions in dilute chemical decontamination formulations. During regeneration of the formulation, the H + from the strong acid cation exchange resin gets released and the metal is absorbed on the resin. The efficiency of the regenerative process depends on the stability constants of the complexes involved and the selectivity on the ion exchange column. The regenerative condition helps to maintain a constant chelating agent concentration and pH during the dissolution experiment. Such a condition is ideal for obtaining data on the dissolution behaviour of the corrosion products with special application to actual reactor decontamination. The ethylenediaminetetraacetic acid (EDTA) based formulation used was found to be ineffective due to the high stability constant of Fe(III)-EDTA complex, which is not easily cleaved by the cation exchange resin. Hence, knowledge of the kinetics of magnetite dissolution under regenerative condition is of primary importance. The 2,6-pyridinedicarboxylic acid formulation is found to be better for the dissolution of Fe 3 O 4 in both static and regenerative modes in the presence of reductants than nitrilotriacetic acid and EDTA. (orig.)

The dissolution kinetics of magnetite under regenerative conditions

Energy Technology Data Exchange (ETDEWEB)

Ranganathan, S. [New Brunswick Univ., Frederiction (Canada). Dept. of Chemical Engineering; Raghavan, P.S.; Gopalan, R.; Srinivasan, M.P.; Narasimhan, S.V. [Water and Steam Chemistry Lab. of Bhabha Atomic Research Centre (BARC) (India)

2004-07-01

Dissolution studies of magnetite were carried out under regenerative conditions in dilute chemical decontamination formulations. During regeneration of the formulation, the H{sup +} from the strong acid cation exchange resin gets released and the metal is absorbed on the resin. The efficiency of the regenerative process depends on the stability constants of the complexes involved and the selectivity on the ion exchange column. The regenerative condition helps to maintain a constant chelating agent concentration and pH during the dissolution experiment. Such a condition is ideal for obtaining data on the dissolution behaviour of the corrosion products with special application to actual reactor decontamination. The ethylenediaminetetraacetic acid (EDTA) based formulation used was found to be ineffective due to the high stability constant of Fe(III)-EDTA complex, which is not easily cleaved by the cation exchange resin. Hence, knowledge of the kinetics of magnetite dissolution under regenerative condition is of primary importance. The 2,6-pyridinedicarboxylic acid formulation is found to be better for the dissolution of Fe{sub 3}O{sub 4} in both static and regenerative modes in the presence of reductants than nitrilotriacetic acid and EDTA. (orig.)

Optimum performance characteristics of a solar-driven Stirling heat engine system

International Nuclear Information System (INIS)

Liao, Tianjun; Lin, Jian

2015-01-01

Graphical abstract: T–S diagram of the SHE cycle. - Highlights: • Based on Lagrange multiplier method, the optimal performance are investigated. • The energy balance between the absorber and the hot side of Stirling heat engine is considered. • The effects of major parameters on the optimal performance are investigated. - Abstract: A solar-driven Stirling heat engine system composed of a Stirling heat engine, a solar collector, and a heat sink is presented, in which the radiation and convection heat losses of the solar collector, the heat-leak between the thermal absorber and heat sink, the regenerative losses of the Stirling heat engine, and the energy balance between the thermal absorber and the high isothermal process of the Stirling heat engine are taken into consideration. Based on the irreversible thermodynamics and Lagrange multiplier method, the maximum power output and the corresponding optimal efficiency of the system are determined and the absorber temperature that maximizes the optimal system efficiency is calculated numerically. The influences of some system parameters such as the concentrating ratio, the volume ratio during the regenerative processes and irreversibilities of heat exchange processes on the optimal efficiency are analyzed in details. The results obtained here may provide a new idea to design practical solar-driven Stirling heat engine system

Regenerative Stem Cell Therapy for Breast Cancer Bone Metastasis

Science.gov (United States)

2015-11-01

1 AD_________________ Award Number: W81XWH-11-1-0593 TITLE: Regenerative Stem Cell Therapy for Breast Cancer Bone Metastasis PRINCIPAL...3. DATES COVERED (From - To) 09/15/2011 - 08/14/2015 4. TITLE AND SUBTITLE Regenerative Stem Cell Therapy for Breast Cancer Bone Metastasis 5a...4 Title of the Grant: Regenerative Stem Cell Therapy for Breast Cancer Bone Metastasis Award number: W81XWH-11-1-0593 Principal Investigator

Regenerative Hydride Heat Pump

Science.gov (United States)

Jones, Jack A.

1992-01-01

Hydride heat pump features regenerative heating and single circulation loop. Counterflow heat exchangers accommodate different temperatures of FeTi and LaNi4.7Al0.3 subloops. Heating scheme increases efficiency.

Combined hydraulic and regenerative braking system

Science.gov (United States)

Venkataperumal, R.R.; Mericle, G.E.

1979-08-09

A combined hydraulic and regenerative braking system and method for an electric vehicle is disclosed. The braking system is responsive to the applied hydraulic pressure in a brake line to control the braking of the vehicle to be completely hydraulic up to a first level of brake line pressure, to be partially hydraulic at a constant braking force and partially regenerative at a linearly increasing braking force from the first level of applied brake line pressure to a higher second level of brake line pressure, to be partially hydraulic at a linearly increasing braking force and partially regenerative at a linearly decreasing braking force from the second level of applied line pressure to a third and higher level of applied line pressure, and to be completely hydraulic at a linearly increasing braking force from the third level to all higher applied levels of line pressure.

Regenerative agriculture: merging farming and natural resource conservation profitably.

Science.gov (United States)

LaCanne, Claire E; Lundgren, Jonathan G

2018-01-01

Most cropland in the United States is characterized by large monocultures, whose productivity is maintained through a strong reliance on costly tillage, external fertilizers, and pesticides (Schipanski et al., 2016). Despite this, farmers have developed a regenerative model of farm production that promotes soil health and biodiversity, while producing nutrient-dense farm products profitably. Little work has focused on the relative costs and benefits of novel regenerative farming operations, which necessitates studying in situ , farmer-defined best management practices. Here, we evaluate the relative effects of regenerative and conventional corn production systems on pest management services, soil conservation, and farmer profitability and productivity throughout the Northern Plains of the United States. Regenerative farming systems provided greater ecosystem services and profitability for farmers than an input-intensive model of corn production. Pests were 10-fold more abundant in insecticide-treated corn fields than on insecticide-free regenerative farms, indicating that farmers who proactively design pest-resilient food systems outperform farmers that react to pests chemically. Regenerative fields had 29% lower grain production but 78% higher profits over traditional corn production systems. Profit was positively correlated with the particulate organic matter of the soil, not yield. These results provide the basis for dialogue on ecologically based farming systems that could be used to simultaneously produce food while conserving our natural resource base: two factors that are pitted against one another in simplified food production systems. To attain this requires a systems-level shift on the farm; simply applying individual regenerative practices within the current production model will not likely produce the documented results.

Autonomous Operation of Super-Regenerative Receiver in BAN

NARCIS (Netherlands)

Kalyanasundaram, P.; Huang, L.; Dolmans, G.; Imamura, K.

2012-01-01

Super-regenerative receiver is one of the potential candidates to achieve ultra low power wireless communication in body area network (BAN). The main limitations of the super-regenerative receiver include the difficulty in choosing a good quench waveform to optimize its sensitivity and selectivity,

Adaptive controller for regenerative and friction braking system

Science.gov (United States)

Davis, Roy I.

1990-01-01

A regenerative and friction braking system for a vehicle having one or more roadwheels driven by an electric traction motor includes a driver responsive device for producing a brake demand signal having a magnitude corresponding to the level of braking force selected by the driver and friction and regenerative brakes operatively connected with the roadwheels of the vehicle. A system according to this invention further includes control means for operating the friction and regenerative braking subsystems so that maximum brake torques sustainable by the roadwheels of the vehicle without skidding or slipping will not be exceeded.

State of the art: stem cells in equine regenerative medicine.

Science.gov (United States)

Lopez, M J; Jarazo, J

2015-03-01

According to Greek mythology, Prometheus' liver grew back nightly after it was removed each day by an eagle as punishment for giving mankind fire. Hence, contrary to popular belief, the concept of tissue and organ regeneration is not new. In the early 20th century, cell culture and ex vivo organ preservation studies by Alexis Carrel, some with famed aviator Charles Lindbergh, established a foundation for much of modern regenerative medicine. While early beliefs and discoveries foreshadowed significant accomplishments in regenerative medicine, advances in knowledge within numerous scientific disciplines, as well as nano- and micromolecular level imaging and detection technologies, have contributed to explosive advances over the last 20 years. Virtually limitless preparations, combinations and applications of the 3 major components of regenerative medicine, namely cells, biomaterials and bioactive molecules, have created a new paradigm of future therapeutic options for most species. It is increasingly clear, however, that despite significant parallels among and within species, there is no 'one-size-fits-all' regenerative therapy. Likewise, a panacea has yet to be discovered that completely reverses the consequences of time, trauma and disease. Nonetheless, there is no question that the promise and potential of regenerative medicine have forever altered medical practices. The horse is a relative newcomer to regenerative medicine applications, yet there is already a large body of work to incorporate novel regenerative therapies into standard care. This review focuses on the current state and potential future of stem cells in equine regenerative medicine. © 2014 EVJ Ltd.

Solar-Electrochemical Power System for a Mars Mission

Science.gov (United States)

Withrow, Colleen A.; Morales, Nelson

1994-01-01

This report documents a sizing study of a variety of solar electrochemical power systems for the intercenter NASA study known as 'Mars Exploration Reference Mission'. Power systems are characterized for a variety of rovers, habitation modules, and space transport vehicles based on requirements derived from the reference mission. The mission features a six-person crew living on Mars for 500 days. Mission power requirements range from 4 kWe to 120 kWe. Primary hydrogen and oxygen fuel cells, regenerative hydrogen and oxygen fuel cells, sodium sulfur batteries advanced photovoltaic solar arrays of gallium arsenide on germanium with tracking and nontracking mechanisms, and tent solar arrays of gallium arsenide on germanium are evaluated and compared.

Platelet rich fibrin - a novel acumen into regenerative endodontic therapy

Directory of Open Access Journals (Sweden)

Kavita Hotwani

2014-02-01

Full Text Available Research into regenerative dentistry has added impetus onto the field of molecular biology. It can be documented as a prototype shift in the therapeutic armamentarium for dental disease. Regenerative endodontic procedures are widely being added to the current armamentarium of pulp therapy procedures. The regenerative potential of platelets has been deliberated. A new family of platelet concentrates called the platelet rich fibrin (PRF has been recently used by several investigators and has shown application in diverse disciplines of dentistry. This paper is intended to add light on the various prospects of PRF and clinical insights to regenerative endodontic therapy.

Performance comparison of different thermodynamic cycles for an innovative central receiver solar power plant

Science.gov (United States)

Reyes-Belmonte, Miguel A.; Sebastián, Andrés; González-Aguilar, José; Romero, Manuel

2017-06-01

The potential of using different thermodynamic cycles coupled to a solar tower central receiver that uses a novel heat transfer fluid is analyzed. The new fluid, named as DPS, is a dense suspension of solid particles aerated through a tubular receiver used to convert concentrated solar energy into thermal power. This novel fluid allows reaching high temperatures at the solar receiver what opens a wide range of possibilities for power cycle selection. This work has been focused into the assessment of power plant performance using conventional, but optimized cycles but also novel thermodynamic concepts. Cases studied are ranging from subcritical steam Rankine cycle; open regenerative Brayton air configurations at medium and high temperature; combined cycle; closed regenerative Brayton helium scheme and closed recompression supercritical carbon dioxide Brayton cycle. Power cycle diagrams and working conditions for design point are compared amongst the studied cases for a common reference thermal power of 57 MWth reaching the central cavity receiver. It has been found that Brayton air cycle working at high temperature or using supercritical carbon dioxide are the most promising solutions in terms of efficiency conversion for the power block of future generation by means of concentrated solar power plants.

An Intelligent Regenerative Braking Strategy for Electric Vehicles

Directory of Open Access Journals (Sweden)

Zhibin Song

2011-09-01

Full Text Available Regenerative braking is an effective approach for electric vehicles (EVs to extend their driving range. A fuzzy-logic-based regenerative braking strategy (RBS integrated with series regenerative braking is developed in this paper to advance the level of energy-savings. From the viewpoint of securing car stability in braking operations, the braking force distribution between the front and rear wheels so as to accord with the ideal distribution curve are considered to prevent vehicles from experiencing wheel lock and slip phenomena during braking. Then, a fuzzy RBS using the driver’s braking force command, vehicle speed, battery SOC, battery temperature are designed to determine the distribution between friction braking force and regenerative braking force to improve the energy recuperation efficiency. The experimental results on an “LF620” prototype EV validated the feasibility and effectiveness of regenerative braking and showed that the proposed fuzzy RBS was endowed with good control performance. The maximum driving range of LF620 EV was improved by 25.7% compared with non-RBS conditions.

Evaluation strategy of regenerative braking energy for supercapacitor vehicle.

Science.gov (United States)

Zou, Zhongyue; Cao, Junyi; Cao, Binggang; Chen, Wen

2015-03-01

In order to improve the efficiency of energy conversion and increase the driving range of electric vehicles, the regenerative energy captured during braking process is stored in the energy storage devices and then will be re-used. Due to the high power density of supercapacitors, they are employed to withstand high current in the short time and essentially capture more regenerative energy. The measuring methods for regenerative energy should be investigated to estimate the energy conversion efficiency and performance of electric vehicles. Based on the analysis of the regenerative braking energy system of a supercapacitor vehicle, an evaluation system for energy recovery in the braking process is established using USB portable data-acquisition devices. Experiments under various braking conditions are carried out. The results verify the higher efficiency of energy regeneration system using supercapacitors and the effectiveness of the proposed measurement method. It is also demonstrated that the maximum regenerative energy conversion efficiency can reach to 88%. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

A Thermally-Regenerative Ammonia-Based Flow Battery for Electrical Energy Recovery from Waste Heat.

Science.gov (United States)

Zhu, Xiuping; Rahimi, Mohammad; Gorski, Christopher A; Logan, Bruce

2016-04-21

Large amounts of low-grade waste heat (temperatures energy can be converted to electricity in battery systems. To improve reactor efficiency, a compact, ammonia-based flow battery (AFB) was developed and tested at different solution concentrations, flow rates, cell pairs, and circuit connections. The AFB achieved a maximum power density of 45 W m(-2) (15 kW m(-3) ) and an energy density of 1260 Wh manolyte (-3) , with a thermal energy efficiency of 0.7 % (5 % relative to the Carnot efficiency). The power and energy densities of the AFB were greater than those previously reported for thermoelectrochemical and salinity-gradient technologies, and the voltage or current could be increased using stacked cells. These results demonstrated that an ammonia-based flow battery is a promising technology to convert low-grade thermal energy to electricity. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Recent considerations in regenerative endodontic treatment approaches

Directory of Open Access Journals (Sweden)

Hacer Aksel

2014-09-01

Conclusion: Although the regenerative treatment approaches have good clinical outcomes in the majority of case reports, the outcomes are unpredictable. Since the current clinical protocols for regenerative endodontics do not fully fulfill the triad of tissue engineering ((growth factors, scaffold and stem cells, further translational studies are required to achieve more pulp- and dentin-like tissue in the root canal system to achieve pulp regeneration.

Regenerative endodontics: barriers and strategies for clinical translation.

Science.gov (United States)

Mao, Jeremy J; Kim, Sahng G; Zhou, Jian; Ye, Ling; Cho, Shoko; Suzuki, Takahiro; Fu, Susan Y; Yang, Rujing; Zhou, Xuedong

2012-07-01

Regenerative endodontics has encountered substantial challenges toward clinical translation. The adoption by the American Dental Association of evoked pulp bleeding in immature permanent teeth is an important step for regenerative endodontics. However, there is no regenerative therapy for most endodontic diseases. Simple recapitulation of cell therapy and tissue engineering strategies that are under development for other organ systems has not led to clinical translation in regeneration endodontics. Recent work using novel biomaterial scaffolds and growth factors that orchestrate the homing of host endogenous cells represents a departure from traditional cell transplantation approaches and may accelerate clinical translation. Copyright © 2012 Elsevier Inc. All rights reserved.

Clinical considerations for regenerative endodontic procedures.

Science.gov (United States)

Geisler, Todd M

2012-07-01

The management of a tooth with incomplete root maturation and a necrotic pulp is an endodontic and a restorative challenge. Apexification procedures alone leave the tooth in a weakened state and at risk for reinfection. Regenerative endodontic procedures potentially offer advantages, including the possibility of hard tissue deposition and continued root development. Case studies have reported regeneration of human pulplike tissues in vivo, but there is no protocol that reliably regenerates pulplike tissue. This article summarizes historical, current, and future regenerative treatment approaches. Copyright © 2012 Elsevier Inc. All rights reserved.

Solar-coupled electric vehicles

International Nuclear Information System (INIS)

Willer, B.

1993-01-01

An electrical drive is an alternative to the present internal combustion engines. The electric car produces no exhaust gas where it is used and drives practically noiselessly. The energy required for driving is usually taken from an electro-chemical battery. The necessary electricity generation generates emission and CO 2 , depending on the primary energy used. An alternative is provided by electricity generation with the aid of regenerative energy. Apart from hydroelectric and wind energy, solar energy can make a considerable contribution in the future. (orig.) [de

Repairing quite swimmingly: advances in regenerative medicine using zebrafish.

Science.gov (United States)

Goessling, Wolfram; North, Trista E

2014-07-01

Regenerative medicine has the promise to alleviate morbidity and mortality caused by organ dysfunction, longstanding injury and trauma. Although regenerative approaches for a few diseases have been highly successful, some organs either do not regenerate well or have no current treatment approach to harness their intrinsic regenerative potential. In this Review, we describe the modeling of human disease and tissue repair in zebrafish, through the discovery of disease-causing genes using classical forward-genetic screens and by modulating clinically relevant phenotypes through chemical genetic screening approaches. Furthermore, we present an overview of those organ systems that regenerate well in zebrafish in contrast to mammalian tissue, as well as those organs in which the regenerative potential is conserved from fish to mammals, enabling drug discovery in preclinical disease-relevant models. We provide two examples from our own work in which the clinical translation of zebrafish findings is either imminent or has already proven successful. The promising results in multiple organs suggest that further insight into regenerative mechanisms and novel clinically relevant therapeutic approaches will emerge from zebrafish research in the future. © 2014. Published by The Company of Biologists Ltd.

Center for Neuroscience & Regenerative Medicine

Data.gov (United States)

Federal Laboratory Consortium — The Center for Neuroscience and Regenerative Medicine (CNRM) was established as a collaborative intramural federal program involving the U.S. Department of Defense...

Stem cell bioprinting for applications in regenerative medicine.

Science.gov (United States)

Tricomi, Brad J; Dias, Andrew D; Corr, David T

2016-11-01

Many regenerative medicine applications seek to harness the biologic power of stem cells in architecturally complex scaffolds or microenvironments. Traditional tissue engineering methods cannot create such intricate structures, nor can they precisely control cellular position or spatial distribution. These limitations have spurred advances in the field of bioprinting, aimed to satisfy these structural and compositional demands. Bioprinting can be defined as the programmed deposition of cells or other biologics, often with accompanying biomaterials. In this concise review, we focus on recent advances in stem cell bioprinting, including performance, utility, and applications in regenerative medicine. More specifically, this review explores the capability of bioprinting to direct stem cell fate, engineer tissue(s), and create functional vascular networks. Furthermore, the unique challenges and concerns related to bioprinting living stem cells, such as viability and maintaining multi- or pluripotency, are discussed. The regenerative capacity of stem cells, when combined with the structural/compositional control afforded by bioprinting, provides a unique and powerful tool to address the complex demands of tissue engineering and regenerative medicine applications. © 2016 New York Academy of Sciences.

Conference Report: 6th Annual International Symposium on Regenerative Rehabilitation.

Science.gov (United States)

Loghmani, M Terry; Roche, Joseph A

2018-04-03

The 6th International Symposium on Regenerative Rehabilitation, hosted by the Alliance for Regenerative Rehabilitation Research and Training (AR 3 T), included a preconference meeting of institutional representatives of the International Consortium of Regenerative Rehabilitation, keynote talks from distinguished scientists, platform and poster presentations from experts and trainees, panel discussions and postconference workshops. The following priorities were identified: increasing rigor in basic, preclinical and clinical studies, especially the use of better controls; developing better outcome measures for preclinical and clinical trials; focusing on developing more tissue-based interventions versus cell-based interventions; including regenerative rehabilitation in curricula of professional programs like occupational and physical therapy; and developing better instruments to quantify rehabilitative interventions.

A high-power compact regenerative amplifier FEL

International Nuclear Information System (INIS)

Nguyen, D.C.; Sheffield, R.L.; Fortgang, C.M.; Kinross-Wright, J.M.; Ebrahim, N.A.; Goldstein, J.C.

1997-01-01

The Regenerative Amplifier FEL (RAFEL) is a new FEL approach aimed at achieving the highest optical power from a compact rf-linac FEL. The key idea is to feed back a small fraction ( 5 in single pass) wiggler to enable the FEL to reach saturation in a few passes. This paper summarizes the design of a high-power compact regenerative amplifier FEL and describes the first experimental demonstration of the RAFEL concept

Early Orthodontic Tooth Movement into Regenerative Bony Defects: A Case Report.

Science.gov (United States)

Tsai, Hui-Chen; Yao, Chung-Chen Jane; Wong, Man-Ying

Early orthodontic tooth movement following regenerative surgery is controversial. In this case, during protraction of the maxillary right first premolar to substitute for the long-term missing maxillary right canine, Bio-Oss and Bio-Gide were used for lateral ridge augmentation at the area of the maxillary right lateral incisor and to cover the denuded surface at the buccal side of the first premolar. Orthodontic tooth movement (OTM) commenced 2 weeks after regenerative surgery. After 8 months, new bone formation was observed on the root surface of the first premolar during implant surgery. A cone beam computed tomography scan taken 1.5 years postsurgery revealed good maintenance of regenerative bone at the same site. This satisfactory outcome of early OTM following regenerative surgery suggests biomechanical stimulation may not jeopardize the regenerative effect.

Regenerative medicine in otorhinolaryngology.

Science.gov (United States)

Wormald, J C R; Fishman, J M; Juniat, S; Tolley, N; Birchall, M A

2015-08-01

Tissue engineering using biocompatible scaffolds, with or without cells, can permit surgeons to restore structure and function following tissue resection or in cases of congenital abnormality. Tracheal regeneration has emerged as a spearhead application of these technologies, whilst regenerative therapies are now being developed to treat most other diseases within otolaryngology. A systematic review of the literature was performed using Ovid Medline and Ovid Embase, from database inception to 15 November 2014. A total of 561 papers matched the search criteria, with 76 fulfilling inclusion criteria. Articles were predominantly pre-clinical animal studies, reflecting the current status of research in this field. Several key human research articles were identified and discussed. The main issues facing research in regenerative surgery are translation of animal model work into human models, increasing stem cell availability so it can be used to further research, and development of better facilities to enable implementation of these advances.

Advancing pig cloning technologies towards application in regenerative medicine.

Science.gov (United States)

Nagashima, H; Matsunari, H; Nakano, K; Watanabe, M; Umeyama, K; Nagaya, M

2012-08-01

Regenerative medicine is expected to make a significant contribution by development of novel therapeutic treatments for intractable diseases and for improving the quality of life of patients. Many advances in regenerative medicine, including basic and translational research, have been developed and tested in experimental animals; pigs have played an important role in various aspects of this work. The value of pigs as a model species is being enhanced by the generation of specially designed animals through cloning and genetic modifications, enabling more sophisticated research to be performed and thus accelerating the clinical application of regenerative medicine. This article reviews the significant aspects of the creation and application of cloned and genetically modified pigs in regenerative medicine research and considers the possible future directions of the technology. We also discuss the importance of reproductive biology as an interface between basic science and clinical medicine. © 2012 Blackwell Verlag GmbH.

Solar thermal aided power generation

International Nuclear Information System (INIS)

Hu, Eric; Yang, YongPing; Nishimura, Akira; Yilmaz, Ferdi; Kouzani, Abbas

2010-01-01

Fossil fuel based power generation is and will still be the back bone of our world economy, albeit such form of power generation significantly contributes to global CO 2 emissions. Solar energy is a clean, environmental friendly energy source for power generation, however solar photovoltaic electricity generation is not practical for large commercial scales due to its cost and high-tech nature. Solar thermal is another way to use solar energy to generate power. Many attempts to establish solar (solo) thermal power stations have been practiced all over the world. Although there are some advantages in solo solar thermal power systems, the efficiencies and costs of these systems are not so attractive. Alternately by modifying, if possible, the existing coal-fired power stations to generate green sustainable power, a much more efficient means of power generation can be reached. This paper presents the concept of solar aided power generation in conventional coal-fired power stations, i.e., integrating solar (thermal) energy into conventional fossil fuelled power generation cycles (termed as solar aided thermal power). The solar aided power generation (SAPG) concept has technically been derived to use the strong points of the two technologies (traditional regenerative Rankine cycle with relatively higher efficiency and solar heating at relatively low temperature range). The SAPG does not only contribute to increase the efficiencies of the conventional power station and reduce its emission of the greenhouse gases, but also provides a better way to use solar heat to generate the power. This paper presents the advantages of the SAPG at conceptual level.

Giant hepatic regenerative nodules in Alagille syndrome

Energy Technology Data Exchange (ETDEWEB)

Rapp, Jordan B. [Lewis Katz School of Medicine at Temple University, Department of Radiology, Temple University Hospital, Philadelphia, PA (United States); Bellah, Richard D.; Anupindi, Sudha A. [The Children' s Hospital of Philadelphia, Department of Radiology, Philadelphia, PA (United States); University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA (United States); Maya, Carolina [The Children' s Hospital of Philadelphia, Department of Radiology, Philadelphia, PA (United States); Pawel, Bruce R. [University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA (United States); The Children' s Hospital of Philadelphia, Department of Pathology and Laboratory Medicine, Philadelphia, PA (United States)

2017-02-15

Children with Alagille syndrome undergo surveillance radiologic examinations as they are at risk for developing cirrhosis and hepatocellular carcinoma. There is limited literature on the imaging of liver masses in Alagille syndrome. We report the ultrasound (US) and magnetic resonance imaging (MRI) appearances of incidental benign giant hepatic regenerative nodules in this population. To describe the imaging findings of giant regenerative nodules in patients with Alagille syndrome. A retrospective search of the hospital database was performed to find all cases of hepatic masses in patients with Alagille syndrome during a 10-year period. Imaging, clinical charts, laboratory data and available pathology were reviewed and analyzed and summarized for each patient. Twenty of 45 patients with confirmed Alagille syndrome had imaging studies. Of those, we identified six with giant focal liver masses. All six patients had large central hepatic masses that were remarkably similar on US and MRI, in addition to having features of cirrhosis. In each case, the mass was located in hepatic segment VIII and imaging showed the mass splaying the main portal venous branches at the hepatic hilum, as well as smaller portal and hepatic venous branches coursing through them. On MRI, signal intensity of the mass was isointense to liver on T1-weighted sequences in four of six patients, but hyperintense on T1 in two of six patients. In all six cases, the mass was hypointense on T2- weighted sequences. The mass post-contrast was isointense to adjacent liver in all phases in five the cases. Five out of six patients had pathological correlation demonstrating preserved ductal architecture confirming the final diagnosis of a regenerative nodule. Giant hepatic regenerative nodules with characteristic US and MR features can occur in patients with Alagille syndrome with underlying cirrhosis. Recognizing these lesions as benign giant hepatic regenerative nodules should, thereby, mitigate any need for

Giant hepatic regenerative nodules in Alagille syndrome

International Nuclear Information System (INIS)

Rapp, Jordan B.; Bellah, Richard D.; Anupindi, Sudha A.; Maya, Carolina; Pawel, Bruce R.

2017-01-01

Children with Alagille syndrome undergo surveillance radiologic examinations as they are at risk for developing cirrhosis and hepatocellular carcinoma. There is limited literature on the imaging of liver masses in Alagille syndrome. We report the ultrasound (US) and magnetic resonance imaging (MRI) appearances of incidental benign giant hepatic regenerative nodules in this population. To describe the imaging findings of giant regenerative nodules in patients with Alagille syndrome. A retrospective search of the hospital database was performed to find all cases of hepatic masses in patients with Alagille syndrome during a 10-year period. Imaging, clinical charts, laboratory data and available pathology were reviewed and analyzed and summarized for each patient. Twenty of 45 patients with confirmed Alagille syndrome had imaging studies. Of those, we identified six with giant focal liver masses. All six patients had large central hepatic masses that were remarkably similar on US and MRI, in addition to having features of cirrhosis. In each case, the mass was located in hepatic segment VIII and imaging showed the mass splaying the main portal venous branches at the hepatic hilum, as well as smaller portal and hepatic venous branches coursing through them. On MRI, signal intensity of the mass was isointense to liver on T1-weighted sequences in four of six patients, but hyperintense on T1 in two of six patients. In all six cases, the mass was hypointense on T2- weighted sequences. The mass post-contrast was isointense to adjacent liver in all phases in five the cases. Five out of six patients had pathological correlation demonstrating preserved ductal architecture confirming the final diagnosis of a regenerative nodule. Giant hepatic regenerative nodules with characteristic US and MR features can occur in patients with Alagille syndrome with underlying cirrhosis. Recognizing these lesions as benign giant hepatic regenerative nodules should, thereby, mitigate any need for

Micro-Scale Regenerative Heat Exchanger

Science.gov (United States)

Moran, Matthew E.; Stelter, Stephan; Stelter, Manfred

2004-01-01

A micro-scale regenerative heat exchanger has been designed, optimized and fabricated for use in a micro-Stirling device. Novel design and fabrication techniques enabled the minimization of axial heat conduction losses and pressure drop, while maximizing thermal regenerative performance. The fabricated prototype is comprised of ten separate assembled layers of alternating metal-dielectric composite. Each layer is offset to minimize conduction losses and maximize heat transfer by boundary layer disruption. A grating pattern of 100 micron square non-contiguous flow passages were formed with a nominal 20 micron wall thickness, and an overall assembled ten-layer thickness of 900 microns. Application of the micro heat exchanger is envisioned in the areas of micro-refrigerators/coolers, micropower devices, and micro-fluidic devices.

Erich Regener and the ionisation maximum of the atmosphere

Science.gov (United States)

Carlson, P.; Watson, A. A.

2014-12-01

In the 1930s the German physicist Erich Regener (1881-1955) did important work on the measurement of the rate of production of ionisation deep under water and in the atmosphere. Along with one of his students, Georg Pfotzer, he discovered the altitude at which the production of ionisation in the atmosphere reaches a maximum, often, but misleadingly, called the Pfotzer maximum. Regener was one of the first to estimate the energy density of cosmic rays, an estimate that was used by Baade and Zwicky to bolster their postulate that supernovae might be their source. Yet Regener's name is less recognised by present-day cosmic ray physicists than it should be, largely because in 1937 he was forced to take early retirement by the National Socialists as his wife had Jewish ancestors. In this paper we briefly review his work on cosmic rays and recommend an alternative naming of the ionisation maximum. The influence that Regener had on the field through his son, his son-in-law, his grandsons and his students, and through his links with Rutherford's group in Cambridge, is discussed in an appendix. Regener was nominated for the Nobel Prize in Physics by Schrödinger in 1938. He died in 1955 at the age of 73.

Electrolyte for batteries with regenerative solid electrolyte interface

Science.gov (United States)

Xiao, Jie; Lu, Dongping; Shao, Yuyan; Bennett, Wendy D.; Graff, Gordon L.; Liu, Jun; Zhang, Ji-Guang

2017-08-01

An energy storage device comprising: an anode; and a solute-containing electrolyte composition wherein the solute concentration in the electrolyte composition is sufficiently high to form a regenerative solid electrolyte interface layer on a surface of the anode only during charging of the energy storage device, wherein the regenerative layer comprises at least one solute or solvated solute from the electrolyte composition.

Regenerative endodontics: A way forward.

Science.gov (United States)

Diogenes, Anibal; Ruparel, Nikita B; Shiloah, Yoav; Hargreaves, Kenneth M

2016-05-01

Immature teeth are susceptible to infections due to trauma, anatomic anomalies, and caries. Traditional endodontic therapies for immature teeth, such as apexification procedures, promote resolution of the disease and prevent future infections. However, these procedures fail to promote continued root development, leaving teeth susceptible to fractures. Regenerative endodontic procedures (REPs) have evolved in the past decade, being incorporated into endodontic practice and becoming a viable treatment alternative for immature teeth. The authors have summarized the status of regenerative endodontics on the basis of the available published studies and provide insight into the different levels of clinical outcomes expected from these procedures. Substantial advances in regenerative endodontics are allowing a better understanding of a multitude of factors that govern stem cell-mediated regeneration and repair of the damaged pulp-dentin complex. REPs promote healing of apical periodontitis, continued radiographic root development, and, in certain cases, vitality responses. Despite the clinical success of these procedures, they appear to promote a guided endodontic repair process rather than a true regeneration of physiological-like tissue. Immature teeth with pulpal necrosis with otherwise poor prognosis can be treated with REPs. These procedures do not preclude the possibility of apexification procedures if attempts are unsuccessful. Therefore, REPs may be considered first treatment options for immature teeth with pulpal necrosis. Copyright © 2016 American Dental Association. Published by Elsevier Inc. All rights reserved.

Platelet concentrates: Bioengineering dentistry′s regenerative dreams

Directory of Open Access Journals (Sweden)

Sushma Naag

2015-01-01

Full Text Available Technological advances in the fields of medicine and allied sciences had given much needed momentum into the field of molecular biology and regenerative medicine. They indeed provided a boost to innovate new yields for both hard tissue and soft tissue regeneration in dentistry. One among them is the use of platelet concentrates (platelet rich plasma [PRP], platelet rich fibrin [PRF]. Autologous concentrate of blood platelets with a suspension of growth factors offers an enhanced healing of hard and soft tissues. It is an auxiliary benefit for an operator to be aware of platelet concentrates and its healing properties for delivering unsurpassed oral health care to patients. The current article outlines the principles, objectives and clinical insight to the regenerative potential of platelet concentrates in various fields of dentistry. The search words of the PubMed data base were PRF and other permutations of keywords such as "PRP dentistry", PRF dentistry, PRF regenerative dentistry.

A Comprehensive Review of the Techniques on Regenerative Shock Absorber Systems

Directory of Open Access Journals (Sweden)

Ran Zhang

2018-05-01

Full Text Available In this paper, the current technologies of the regenerative shock absorber systems have been categorized and evaluated. Three drive modes of the regenerative shock absorber systems, namely the direct drive mode, the indirect drive mode and hybrid drive mode are reviewed for their readiness to be implemented. The damping performances of the three different modes are listed and compared. Electrical circuit and control algorithms have also been evaluated to maximize the power output and to deliver the premium ride comfort and handling performance. Different types of parameterized road excitations have been applied to vehicle suspension systems to investigate the performance of the regenerative shock absorbers. The potential of incorporating nonlinearity into the regenerative shock absorber design analysis is discussed. The research gaps for the comparison of the different drive modes and the nonlinearity analysis of the regenerative shock absorbers are identified and, the corresponding research questions have been proposed for future work.

Perivascular cells for regenerative medicine

NARCIS (Netherlands)

M. Crisan (Mihaela); M. Corselli (Mirko); W.C. Chen (William); B. Péault (Bruno)

2012-01-01

textabstractMesenchymal stem/stromal cells (MSC) are currently the best candidate therapeutic cells for regenerative medicine related to osteoarticular, muscular, vascular and inflammatory diseases, although these cells remain heterogeneous and necessitate a better biological characterization. We

The past, present and future of ligament regenerative engineering.

Science.gov (United States)

Mengsteab, Paulos Y; Nair, Lakshmi S; Laurencin, Cato T

2016-12-01

Regenerative engineering has been defined as the convergence of Advanced Materials Sciences, Stem Cell Sciences, Physics, Developmental Biology and Clinical Translation for the regeneration of complex tissues and organ systems. Anterior cruciate ligament (ACL) reconstruction necessitates the regeneration of bone, ligament and their interface to achieve superior clinical results. In the past, the ACL has been repaired with the use of autologous and allogeneic grafts, which have their respective drawbacks. Currently, investigations on the use of biodegradable matrices to achieve knee stability and permit tissue regeneration are making promising advancements. In the future, utilizing regenerative biology cues to induce an endogenous regenerative response may aid the enhancement of clinical ACL reconstruction outcomes.

Regenerative medicine: looking backward 10 years further on.

Science.gov (United States)

Kemp, Paul

2016-12-01

The last decade has seen considerable changes in the Regenerative Medicine industry, but unfortunately the hope for numerous treatments that 'replace or regenerate human cells, tissues or organs to restore or establish normal function' has not yet emerged. In contrast to this, there have been major advances in the field of cellular immunotherapy though some do not consider these to be Regenerative Medicines. Regulatory changes have in some cases improved the route to a marketing license but they have not been matched by clarification of the complex, national reimbursement processes for cell-based treatments and this has adversely affected a number of leading Regenerative Medicine Companies. The review considers the direction that the industry may go in the future in relation to scientific, manufacturing and clinical strategies which may improve the rate of success of new therapies..

Regenerative Endodontics: A Road Less Travelled

Science.gov (United States)

Bansal, Ramta; Mittal, Sunandan; Kumar, Tarun; Kaur, Dilpreet

2014-01-01

Although traditional approaches like root canal therapy and apexification procedures have been successful in treating diseased or infected root canals, but these modalities fail to re-establish healthy pulp tissue in treated teeth. Regeneration-based approaches aims to offer high levels of success by replacing diseased or necrotic pulp tissues with healthy pulp tissue to revitalize teeth. The applications of regenerative approaches in dental clinics have potential to dramatically improve patients’ quality of life. This review article offers a detailed overview of present regenerative endodontic approaches aiming to revitalize teeth and also outlines the problems to be dealt before this emerging field contributes to clinical treatment protocols. It conjointly covers the basic trilogy elements of tissue engineering. PMID:25478476

Experimental study of regenerative desiccant integrated solar dryer with and without reflective mirror

Energy Technology Data Exchange (ETDEWEB)

Shanmugam, V. [Department of Mechanical Engineering, Sathyabama University, Chennai, 600 119 (India); Natarajan, E. [Institute for Energy Studies, College of Engineering, Anna University, Chennai, 600 025 (India)

2007-06-15

An indirect forced convection with desiccant integrated solar dryer has been built and tested. The main parts are: a flat plate solar air collector, a drying chamber, desiccant bed and a centrifugal blower. The system is operated in two modes, sunshine hours and off sunshine hours. During sun shine hours the hot air from the flat plate collector is forced to the drying chamber for drying the product and simultaneously the desiccant bed receives solar radiation directly and through the reflected mirror. In the off sunshine hours, the dryer is operated by circulating the air inside the drying chamber through the desiccant bed by a reversible fan. The dryer is used to dry 20 kg of green peas and pineapple slices. Drying experiments were conducted with and without the integration of desiccant unit. The effect of reflective mirror on the drying potential of desiccant unit was also investigated. With the inclusion of reflective mirror, the drying potential of the desiccant material is increased by 20% and the drying time is reduced. The drying efficiency of the system varies between 43% and 55% and the pick-up efficiency varies between 20% and 60%, respectively. Approximately in all the drying experiments 60% of moisture is removed by air heated using solar energy and the remainder by the desiccant. The inclusion of reflective mirror on the desiccant bed makes faster regeneration of the desiccant material. (author)

Solar thermal power plants simulation using the TRNSYS software

Energy Technology Data Exchange (ETDEWEB)

Popel, O.S.; Frid, S.E.; Shpilrain, E.E. [Institute for High Temperatures, Russian Academy of Sciences (IVTAN), Moscow (Russian Federation)

1999-03-01

The paper describes activity directed on the TRNSYS software application for mathematical simulation of solar thermal power plants. First stage of developments has been devoted to simulation and thermodynamic analysis of the Hybrid Solar-Fuel Thermal Power Plants (HSFTPP) with gas turbine installations. Three schemes of HSFTPP, namely: Gas Turbine Regenerative Cycle, Brayton Cycle with Steam Injection and Combined Brayton-Rankine Cycle,- have been assembled and tested under the TRNSYS. For this purpose 18 new models of the schemes components (gas and steam turbines, compressor, heat-exchangers, steam generator, solar receiver, condenser, controllers, etc) have been elaborated and incorporated into the TRNSYS library of 'standard' components. The authors do expect that this initiative and received results will stimulate experts involved in the mathematical simulation of solar thermal power plants to join the described activity to contribute to acceleration of development and expansion of 'Solar Thermal Power Plants' branch of the TRNSYS. The proposed approach could provide an appropriate basis for standardization of analysis, models and assumptions for well-founded comparison of different schemes of advanced solar power plants. (authors)

Reflective Self-Regenerative Systems Architecture Study

National Research Council Canada - National Science Library

Pu, Carlton; Blough, Douglas

2006-01-01

In this study, we develop the Reflective Self-Regenerative Systems (RSRS) architecture in detail, describing the internal structure of each component and the mutual invocations among the components...

Optimal thermoeconomic performance of an irreversible regenerative ferromagnetic Ericsson refrigeration cycle

International Nuclear Information System (INIS)

Xu, Zhichao; Guo, Juncheng; Lin, Guoxing; Chen, Jincan

2016-01-01

On the basis of the Langevin theory of classical statistical mechanics, the magnetization, entropy, and iso-field heat capacity of ferromagnetic materials are analyzed and their mathematical expressions are derived. An irreversible regenerative Ericsson refrigeration cycle by using a ferromagnetic material as the working substance is established, in which finite heat capacity rates of low and high temperature reservoirs, non-perfect regenerative heat of the refrigeration cycle, additional regenerative heat loss, etc. are taken into account. Based on the regenerative refrigeration cycle model, a thermoeconomic function is introduced as one objective function and optimized with respect to the temperatures of the working substance in the two iso-thermal processes. By means of numerical calculation, the effects of the effective factor of the heat exchangers in high/low temperature reservoir sides, efficiency of the regenerator, heat capacity rate of the low temperature reservoir, and applied magnetic field on the optimal thermoeconomic function as well as the corresponding cooling rate and coefficient of performance are revealed. The results obtained in this paper can provide some theoretical guidance for the optimal design of actual regenerative magnetic refrigerator cycle. - Highlights: • Thermodynamic performance of ferromagnetic material is analyzed. • An irreversible regenerative ferromagnetic Ericsson refrigeration cycle is set up. • The thermoeconomic objective function is introduced and optimized. • Impacts of the thermoeconomic and other parameters are discussed.

Regenerative braking systems with torsional springs made of carbon nanotube yarn

International Nuclear Information System (INIS)

Liu, S; Martin, C; Livermore, C; Lashmore, D; Schauer, M

2014-01-01

The demonstration of large stroke, high energy density and high power density torsional springs based on carbon nanotube (CNT) yarns is reported, as well as their application as an energy-storing actuator for regenerative braking systems. Originally untwisted CNT yarn is cyclically loaded and unloaded in torsion, with the maximum rotation angle increasing until failure. The maximum extractable energy density is measured to be as high as 6.13 kJ/kg. The tests also reveal structural reorganization and hysteresis in the torsional loading curves. A regenerative braking system is built to capture the kinetic energy of a wheel and store it as elastic energy in twisted CNT yarns. When the yam's twist is released, the stored energy reaccelerates the wheel. The measured energy and mean power densities of the CNT yarns in the simple regenerative braking system are up to 4.69 kJ/kg and 1.21 kW/kg, respectively. A slightly lower energy density of up to 1.23 kJ/kg and a 0.29 kW/kg mean power density are measured for the CNT yarns in a more complex system that mimics a unidirectional rotating regenerative braking mechanism. The lower energy densities for CNT yarns in the regenerative braking systems as compared with the yarns themselves reflect the frictional losses of the regenerative systems

Regenerative braking systems with torsional springs made of carbon nanotube yarn

Science.gov (United States)

Liu, S.; Martin, C.; Lashmore, D.; Schauer, M.; Livermore, C.

2014-11-01

The demonstration of large stroke, high energy density and high power density torsional springs based on carbon nanotube (CNT) yarns is reported, as well as their application as an energy-storing actuator for regenerative braking systems. Originally untwisted CNT yarn is cyclically loaded and unloaded in torsion, with the maximum rotation angle increasing until failure. The maximum extractable energy density is measured to be as high as 6.13 kJ/kg. The tests also reveal structural reorganization and hysteresis in the torsional loading curves. A regenerative braking system is built to capture the kinetic energy of a wheel and store it as elastic energy in twisted CNT yarns. When the yam's twist is released, the stored energy reaccelerates the wheel. The measured energy and mean power densities of the CNT yarns in the simple regenerative braking system are up to 4.69 kJ/kg and 1.21 kW/kg, respectively. A slightly lower energy density of up to 1.23 kJ/kg and a 0.29 kW/kg mean power density are measured for the CNT yarns in a more complex system that mimics a unidirectional rotating regenerative braking mechanism. The lower energy densities for CNT yarns in the regenerative braking systems as compared with the yarns themselves reflect the frictional losses of the regenerative systems.

Regenerative Intelligent Brake Control for Electric Motorcycles

Directory of Open Access Journals (Sweden)

Juan Jesús Castillo Aguilar

2017-10-01

Full Text Available Vehicle models whose propulsion system is based on electric motors are increasing in number within the automobile industry. They will soon become a reliable alternative to vehicles with conventional propulsion systems. The main advantages of this type of vehicles are the non-emission of polluting gases and noise and the effectiveness of electric motors compared to combustion engines. Some of the disadvantages that electric vehicle manufacturers still have to solve are their low autonomy due to inefficient energy storage systems, vehicle cost, which is still too high, and reducing the recharging time. Current regenerative systems in motorcycles are designed with a low fixed maximum regeneration rate in order not to cause the rear wheel to slip when braking with the regenerative brake no matter what the road condition is. These types of systems do not make use of all the available regeneration power, since more importance is placed on safety when braking. An optimized regenerative braking strategy for two-wheeled vehicles is described is this work. This system is designed to recover the maximum energy in braking processes while maintaining the vehicle’s stability. In order to develop the previously described regenerative control, tyre forces, vehicle speed and road adhesion are obtained by means of an estimation algorithm. A based-on-fuzzy-logic algorithm is programmed to carry out an optimized control with this information. This system recuperates maximum braking power without compromising the rear wheel slip and safety. Simulations show that the system optimizes energy regeneration on every surface compared to a constant regeneration strategy.

New exergy analysis of a regenerative closed Brayton cycle

International Nuclear Information System (INIS)

Naserian, Mohammad Mahdi; Farahat, Said; Sarhaddi, Faramarz

2017-01-01

Highlights: • The maximum power is studied relating to time and size constraints variations. • The influence of time and size constraints on exergy destruction are investigated. • The definitions of heat exergy, and second law efficiency are modified. - Abstract: In this study, the optimal performance of a regenerative closed Brayton cycle is sought through power maximization. Optimization is performed on the output power as the objective function using genetic algorithm. In order to take into account the time and the size constraints in current problem, the dimensionless mass-flow parameter is used. The influence of the unavoidable exergy destruction due to finite-time constraint is taken into account by developing the definition of heat exergy. Finally, the improved definitions are proposed for heat exergy, and the second law efficiency. Moreover, the new definitions will be compared with the conventional ones. For example, at a specified dimensionless mass-flow parameter, exergy overestimation in conventional definition, causes about 31% lower estimation of the second law efficiency. These results could be expected to be utilized in future solar thermal Brayton cycle assessment and optimization.

Fuzzy logic electric vehicle regenerative antiskid braking and traction control system

Science.gov (United States)

Cikanek, Susan R.

1994-01-01

An regenerative antiskid braking and traction control system using fuzzy logic for an electric or hybrid vehicle having a regenerative braking system operatively connected to an electric traction motor, and a separate hydraulic braking system includes sensors for monitoring present vehicle parameters and a processor, responsive to the sensors, for calculating vehicle parameters defining the vehicle behavior not directly measurable by the sensor and determining if regenerative antiskid braking control, requiring hydraulic braking control, and requiring traction control are required. The processor then employs fuzzy logic based on the determined vehicle state and provides command signals to a motor controller to control operation of the electric traction motor and to the brake controller to control fluid pressure applied at each vehicle wheel to provide the appropriate regenerative braking control, hydraulic braking control, and traction control.

Human resource development contributes to the creation of outstanding regenerative medicine products

Directory of Open Access Journals (Sweden)

Fusako Nishigaki

2017-12-01

Full Text Available Regenerative medicine is currently the focus of global attention. Countries all around the world are actively working to create new regenerative treatment modalities through pioneering research and novel technologies. This is wonderful news for patients who could not be treated with existing medical options. New venture businesses and companies are being established in regenerative medicine and their rapid industrialization is anticipated. However, to ensure high-quality products, human resources qualified in research and development and the manufacturing of these products are essential. The Forum for Innovative Regenerative Medicine (FIRM conducted a questionnaire of its industry members to examine the training and hiring of people in research and development, product creation, manufacturing, and more. Regenerative medicine is a brand new field; thus, many different businesses will need to cooperate together. People with a broad range of technical skills, abilities, and knowledge will be in demand, with various levels of expertise, from basic to advanced.

Bioprinting in Regenerative Medicine

Directory of Open Access Journals (Sweden)

Manuela Monti

2016-02-01

Full Text Available Prof. Turksen is a very well known scientist in the stem cell biology field and he is also internationally known for his fundamental studies on claudin-6. In addition to his research activity he is editor for the Stem Cell Biology and Regenerative Medicine series (Humana Press and editor-in-chief of Stem Cell Reviews and Reports.....

Fuzzy logic electric vehicle regenerative antiskid braking and traction control system

Science.gov (United States)

Cikanek, S.R.

1994-10-25

An regenerative antiskid braking and traction control system using fuzzy logic for an electric or hybrid vehicle having a regenerative braking system operatively connected to an electric traction motor, and a separate hydraulic braking system includes sensors for monitoring present vehicle parameters and a processor, responsive to the sensors, for calculating vehicle parameters defining the vehicle behavior not directly measurable by the sensor and determining if regenerative antiskid braking control, requiring hydraulic braking control, and requiring traction control are required. The processor then employs fuzzy logic based on the determined vehicle state and provides command signals to a motor controller to control operation of the electric traction motor and to the brake controller to control fluid pressure applied at each vehicle wheel to provide the appropriate regenerative braking control, hydraulic braking control, and traction control. 123 figs.

Induced pluripotent stem cells for regenerative medicine.

Science.gov (United States)

Hirschi, Karen K; Li, Song; Roy, Krishnendu

2014-07-11

With the discovery of induced pluripotent stem (iPS) cells, it is now possible to convert differentiated somatic cells into multipotent stem cells that have the capacity to generate all cell types of adult tissues. Thus, there is a wide variety of applications for this technology, including regenerative medicine, in vitro disease modeling, and drug screening/discovery. Although biological and biochemical techniques have been well established for cell reprogramming, bioengineering technologies offer novel tools for the reprogramming, expansion, isolation, and differentiation of iPS cells. In this article, we review these bioengineering approaches for the derivation and manipulation of iPS cells and focus on their relevance to regenerative medicine.

Regenerative engineering

CERN Document Server

Laurencin, Cato T

2013-01-01

Regenerative Engineering: The Future of Medicine Saadiq F. El-Amin III , MD , PhD; Joylene W.L. Thomas, MD ; Ugonna N. Ihekweazu, MD ; Mia D. Woods, MS; and Ashim Gupta, MSCell Biology Gloria Gronowicz, PhD and Karen Sagomonyants, DMDStem Cells and Tissue Regeneration Kristen Martins-Taylor, PhD; Xiaofang Wang, MD , PhD; Xue-Jun Li, PhD; and Ren-He Xu, MD , PhDIntroduction to Materials Science Sangamesh G. Kumbar, PhD and Cato T. Laurencin, MD , PhDBiomaterials A. Jon Goldberg, PhD and Liisa T. Kuhn, PhDIn Vitro Assessment of Cell-Biomaterial Interactions Yong Wang, PhDHost Response to Biomate

Biomolecule delivery to engineer the cellular microenvironment for regenerative medicine.

Science.gov (United States)

Bishop, Corey J; Kim, Jayoung; Green, Jordan J

2014-07-01

To realize the potential of regenerative medicine, controlling the delivery of biomolecules in the cellular microenvironment is important as these factors control cell fate. Controlled delivery for tissue engineering and regenerative medicine often requires bioengineered materials and cells capable of spatiotemporal modulation of biomolecule release and presentation. This review discusses biomolecule delivery from the outside of the cell inwards through the delivery of soluble and insoluble biomolecules as well as from the inside of the cell outwards through gene transfer. Ex vivo and in vivo therapeutic strategies are discussed, as well as combination delivery of biomolecules, scaffolds, and cells. Various applications in regenerative medicine are highlighted including bone tissue engineering and wound healing.

SPE (tm) regenerative hydrogen/oxygen fuel cells for extraterrestrial surface and microgravity applications

Science.gov (United States)

Mcelroy, J. F.

1990-01-01

Viewgraphs on SPE regenerative hydrogen/oxygen fuel cells for extraterrestrial surface and microgravity applications are presented. Topics covered include: hydrogen-oxygen regenerative fuel cell energy storage system; electrochemical cell reactions; SPE cell voltage stability; passive water removal SPE fuel cell; fuel cell performance; SPE water electrolyzers; hydrophobic oxygen phase separator; hydrophilic/electrochemical hydrogen phase separator; and unitized regenerative fuel cell.

Electric vehicle regenerative antiskid braking and traction control system

Science.gov (United States)

Cikanek, S.R.

1995-09-12

An antiskid braking and traction control system for an electric or hybrid vehicle having a regenerative braking system operatively connected to an electric traction motor, and a separate hydraulic braking system includes one or more sensors for monitoring present vehicle parameters and a processor, responsive to the sensors, for calculating vehicle parameters defining the vehicle behavior not directly measurable by the sensors and determining if regenerative antiskid braking control, requiring hydraulic braking control, or requiring traction control are required. The processor then employs a control strategy based on the determined vehicle state and provides command signals to a motor controller to control the operation of the electric traction motor and to a brake controller to control fluid pressure applied at each vehicle wheel to provide the appropriate regenerative antiskid braking control, hydraulic braking control, and traction control. 10 figs.

Electric vehicle regenerative antiskid braking and traction control system

Science.gov (United States)

Cikanek, Susan R.

1995-01-01

An antiskid braking and traction control system for an electric or hybrid vehicle having a regenerative braking system operatively connected to an electric traction motor, and a separate hydraulic braking system includes one or more sensors for monitoring present vehicle parameters and a processor, responsive to the sensors, for calculating vehicle parameters defining the vehicle behavior not directly measurable by the sensors and determining if regenerative antiskid braking control, requiring hydrualic braking control, or requiring traction control are required. The processor then employs a control strategy based on the determined vehicle state and provides command signals to a motor controller to control the operation of the electric traction motor and to a brake controller to control fluid pressure applied at each vehicle wheel to provide the appropriate regenerative antiskid braking control, hydraulic braking control, and traction control.

Regenerative strategies for the treatment of knee joint disabilities

CERN Document Server

Reis, Rui

2017-01-01

This book presents regenerative strategies for the treatment of knee joint disabilities. The book is composed of four main sections totaling 19 chapters which review the current knowledge on the clinical management and preclinical regenerative strategies. It examines the role of different natural-based biomaterials as scaffolds and implants for addressing different tissue lesions in the knee joint. Section one provides an updated and comprehensive discussion on articular cartilage tissue regeneration. Section two focuses on the important contributions for bone and osteochondral tissue engineering. Section three overview the recent advances on meniscus repair/regeneration strategies. Finally, section four further discusses the current strategies for treatment of ligament lesions. Each chapter is prepared by world know expert on their fields, so we do firmly believe that the proposed book will be a reference in the area of biomaterials for regenerative medicine.

Design and experiment study of a semi-active energy-regenerative suspension system

International Nuclear Information System (INIS)

Shi, Dehua; Chen, Long; Wang, Ruochen; Jiang, Haobin; Shen, Yujie

2015-01-01

A new kind of semi-active energy-regenerative suspension system is proposed to recover suspension vibration energy, as well as to reduce the suspension cost and demands for the motor-rated capacity. The system consists of an energy-regenerative damper and a DC-DC converter-based energy-regenerative circuit. The energy-regenerative damper is composed of an electromagnetic linear motor and an adjustable shock absorber with three regulating levels. The linear motor just works as the generator to harvest the suspension vibration energy. The circuit can be used to improve the system’s energy-regenerative performance and to continuously regulate the motor’s electromagnetic damping force. Therefore, although the motor works as a generator and damps the isolation without an external power source, the motor damping force is controllable. The damping characteristics of the system are studied based on a two degrees of freedom vehicle vibration model. By further analyzing the circuit operation characteristics under different working modes, the double-loop controller is designed to track the desired damping force. The external-loop is a fuzzy controller that offers the desired equivalent damping. The inner-loop controller, on one hand, is used to generate the pulse number and the frequency to control the angle and the rotational speed of the step motor; on the other hand, the inner-loop is used to offer the duty cycle of the energy-regenerative circuit. Simulations and experiments are conducted to validate such a new suspension system. The results show that the semi-active energy-regenerative suspension can improve vehicle ride comfort with the controllable damping characteristics of the linear motor. Meanwhile, it also ensures energy regeneration. (paper)

Stem Cell Therapy: Repurposing Cell-Based Regenerative Medicine Beyond Cell Replacement.

Science.gov (United States)

Napoli, Eleonora; Lippert, Trenton; Borlongan, Cesar V

2018-02-27

Stem cells exhibit simple and naive cellular features, yet their exact purpose for regenerative medicine continues to elude even the most elegantly designed research paradigms from developmental biology to clinical therapeutics. Based on their capacity to divide indefinitely and their dynamic differentiation into any type of tissue, the advent of transplantable stem cells has offered a potential treatment for aging-related and injury-mediated diseases. Recent laboratory evidence has demonstrated that transplanted human neural stem cells facilitate endogenous reparative mechanisms by initiating multiple regenerative processes in the brain neurogenic areas. Within these highly proliferative niches reside a myriad of potent regenerative molecules, including anti-inflammatory cytokines, proteomes, and neurotrophic factors, altogether representing a biochemical cocktail vital for restoring brain function in the aging and diseased brain. Here, we advance the concept of therapeutically repurposing stem cells not towards cell replacement per se, but rather exploiting the cells' intrinsic properties to serve as the host brain regenerative catalysts.

Dental pulp stem cells: function, isolation and applications in regenerative medicine.

Science.gov (United States)

Tatullo, Marco; Marrelli, Massimo; Shakesheff, Kevin M; White, Lisa J

2015-11-01

Dental pulp stem cells (DPSCs) are a promising source of cells for numerous and varied regenerative medicine applications. Their natural function in the production of odontoblasts to create reparative dentin support applications in dentistry in the regeneration of tooth structures. However, they are also being investigated for the repair of tissues outside of the tooth. The ease of isolation of DPSCs from discarded or removed teeth offers a promising source of autologous cells, and their similarities with bone marrow stromal cells (BMSCs) suggest applications in musculoskeletal regenerative medicine. DPSCs are derived from the neural crest and, therefore, have a different developmental origin to BMSCs. These differences from BMSCs in origin and phenotype are being exploited in neurological and other applications. This review briefly highlights the source and functions of DPSCs and then focuses on in vivo applications across the breadth of regenerative medicine. © 2014 The Authors. Journal of Tissue Engineering and Regenerative Medicine published by John Wiley & Sons, Ltd.

Regenerative Medicine: Advances from Developmental to Degenerative Diseases.

Science.gov (United States)

Blair, Nicholas F; Frith, Thomas J R; Barbaric, Ivana

2017-01-01

Chronic tissue and organ failure caused by an injury, disease, ageing or congenital defects represents some of the most complex therapeutic challenges and poses a significant financial healthcare burden. Regenerative medicine strategies aim to fulfil the unmet clinical need by restoring the normal tissue function either through stimulating the endogenous tissue repair or by using transplantation strategies to replace the missing or defective cells. Stem cells represent an essential pillar of regenerative medicine efforts as they provide a source of progenitors or differentiated cells for use in cell replacement therapies. Whilst significant leaps have been made in controlling the stem cell fates and differentiating them to cell types of interest, transitioning bespoke cellular products from an academic environment to off-the-shelf clinical treatments brings about a whole new set of challenges which encompass manufacturing, regulatory and funding issues. Notwithstanding the need to resolve such issues before cell replacement therapies can benefit global healthcare, mounting progress in the field has highlighted regenerative medicine as a realistic prospect for treating some of the previously incurable conditions.

Prospective regenerative medicine therapies for obstetric trauma-induced fecal incontinence.

Science.gov (United States)

Parmar, Nina; Kumar, Lalit; Emmanuel, Anton; Day, Richard M

2014-01-01

Fecal incontinence is a major public health issue that has yet to be adequately addressed. Obstetric trauma and injury to the anal sphincter muscles are the most common cause of fecal incontinence. New therapies are emerging aimed at repair or regeneration of sphincter muscle and restoration of continence. While regenerative medicine offers an attractive option for fecal incontinence there are currently no validated techniques using this approach. Although many challenges are yet to be resolved, the advent of regenerative medicine is likely to offer disruptive technologies to treat and possibly prevent the onset of this devastating condition. This article provides a review on regenerative medicine approaches for treating fecal incontinence and a critique of the current landscape in this area.

Regenerative feedback resonant circuit

Science.gov (United States)

Jones, A. Mark; Kelly, James F.; McCloy, John S.; McMakin, Douglas L.

2014-09-02

A regenerative feedback resonant circuit for measuring a transient response in a loop is disclosed. The circuit includes an amplifier for generating a signal in the loop. The circuit further includes a resonator having a resonant cavity and a material located within the cavity. The signal sent into the resonator produces a resonant frequency. A variation of the resonant frequency due to perturbations in electromagnetic properties of the material is measured.

Carbon nanotube torsional springs for regenerative braking systems

Science.gov (United States)

Liu, Sanwei; Martin, Corbin; Lashmore, David; Schauer, Mark; Livermore, Carol

2015-10-01

The modeling and demonstration of large stroke, high energy density and high power density torsional springs based on carbon nanotube (CNT) yarns is reported, as well as their application as energy-storing actuators for regenerative braking systems. An originally untwisted CNT yarn is cyclically loaded and unloaded in torsion, with the maximum rotation angle increasing incrementally until failure. The measured average extractable energy density values are 2.9 kJ kg-1  ±  1.2 kJ kg-1 and 3.4 kJ kg-1  ±  0.4 kJ kg-1 for 1-ply CNT yarns and 2-ply CNT yarns, respectively. Additionally, a regenerative braking system is demonstrated to capture the kinetic energy of a wheel and store it as elastic energy in twisted CNT yarns. When the yarn’s twist is released, the stored energy reaccelerates the wheel. The measured energy and mean power densities of the CNT yarns in the simple regenerative braking setup are on average 3.3 kJ kg-1 and 0.67 kW kg-1, respectively, with maximum measured values of up to 4.7 kJ kg-1 and 1.2 kW kg-1, respectively. A slightly lower energy density of up to 1.2 kJ kg-1 and a 0.29 kW kg-1 mean power density are measured for CNT yarns in a more complex setup that mimics a unidirectional rotating regenerative braking mechanism.

A survey of attitude and opinions of endodontic residents towards regenerative endodontics

Science.gov (United States)

Utneja, Shivani; Nawal, Ruchika Roongta; Ansari, Mohammed Irfan; Talwar, Sangeeta; Verma, Mahesh

2013-01-01

Aim: The objective of this survey was to study the level of awareness, current state of knowledge and opinions towards regenerative endodontic treatments amongst the endodontic residents of India. Settings and Design: Questionnaire based survey was designed. Materials and Methods: After approval from the organizing committee of 26th Federation of Operative Dentistry of India and 19th Indian Endodontic Society National conference 2011, 200 copies of the questionnaire were circulated amongst the endodontic residents in conservative dentistry and endodontics at various colleges across the country about regenerative endodontic procedures. The survey included profile of the respondents and consisted of 23 questions about their knowledge, attitude and opinions regarding use of these procedures as part of future dental treatment. Results: The survey showed that half the participants (50.6%) had received continued education in stem cells and/or regenerative dental treatments. The majority of participants were of the opinion (86.6%) that regenerative therapy should be incorporated into dentistry, and most of them (88%) were willing to acquire training in learning this new treatment strategy. The results indicated that half of the participants (52.6%) were already using some type of regenerative therapy in their clinical practice; however, with a majority of these limited to use of membranes, scaffolds or bioactive materials. Conclusions: These results reflect that endodontic residents are optimistic about the use of regenerative endodontic procedures; however, a need for more research and training was felt. PMID:23956532

Regenerative Engineering and Bionic Limbs.

Science.gov (United States)

James, Roshan; Laurencin, Cato T

2015-03-01

Amputations of the upper extremity are severely debilitating, current treatments support very basic limb movement, and patients undergo extensive physiotherapy and psychological counselling. There is no prosthesis that allows the amputees near-normal function. With increasing number of amputees due to injuries sustained in accidents, natural calamities and international conflicts, there is a growing requirement for novel strategies and new discoveries. Advances have been made in technological, material and in prosthesis integration where researchers are now exploring artificial prosthesis that integrate with the residual tissues and function based on signal impulses received from the residual nerves. Efforts are focused on challenging experts in different disciplines to integrate ideas and technologies to allow for the regeneration of injured tissues, recording on tissue signals and feed-back to facilitate responsive movements and gradations of muscle force. A fully functional replacement and regenerative or integrated prosthesis will rely on interface of biological process with robotic systems to allow individual control of movement such as at the elbow, forearm, digits and thumb in the upper extremity. Regenerative engineering focused on the regeneration of complex tissue and organ systems will be realized by the cross-fertilization of advances over the past thirty years in the fields of tissue engineering, nanotechnology, stem cell science, and developmental biology. The convergence of toolboxes crated within each discipline will allow interdisciplinary teams from engineering, science, and medicine to realize new strategies, mergers of disparate technologies, such as biophysics, smart bionics, and the healing power of the mind. Tackling the clinical challenges, interfacing the biological process with bionic technologies, engineering biological control of the electronic systems, and feed-back will be the important goals in regenerative engineering over the next

Nanotechnology and regenerative therapeutics in plastic surgery: The next frontier

Science.gov (United States)

Tan, Aaron; Chawla, Reema; Natasha, G; Mahdibeiraghdar, Sara; Jeyaraj, Rebecca; Rajadas, Jayakumar; Hamblin, Michael R.; Seifalian, Alexander M.

2015-01-01

Summary The rapid ascent of nanotechnology and regenerative therapeutics as applied to medicine and surgery has seen an exponential rise in the scale of research generated in this field. This is evidenced not only by the sheer volume of papers dedicated to nanotechnology but also in a large number of new journals dedicated to nanotechnology and regenerative therapeutics specifically to medicine and surgery. Aspects of nanotechnology that have already brought benefits to these areas include advanced drug delivery platforms, molecular imaging and materials engineering for surgical implants. Particular areas of interest include nerve regeneration, burns and wound care, artificial skin with nanoelectronic sensors and head and neck surgery. This study presents a review of nanotechnology and regenerative therapeutics, with focus on its applications and implications in plastic surgery. PMID:26422652

LOX/Methane Regeneratively-Cooled Rocket Engine Development

Data.gov (United States)

National Aeronautics and Space Administration — The purpose of this project is to advance the technologies required to build a subcritical regeneratively cooled liquid oxygen/methane rocket combustion chamber for...

From regenerative dentistry to regenerative medicine: progress, challenges, and potential applications of oral stem cells

Directory of Open Access Journals (Sweden)

Xiao L

2014-12-01

Full Text Available Li Xiao,1 Masanori Nasu2 1Department of Pharmacology, 2Research Center, The Nippon Dental University, Tokyo, Japan Abstract: Adult mesenchymal stem cells (MSCs and epithelial stem cells play essential roles in tissue repair and self-healing. Oral MSCs and epithelial stem cells can be isolated from adult human oral tissues, for example, teeth, periodontal ligament, and gingiva. Cocultivated adult oral epithelial stem cells and MSCs could represent some developmental events, such as epithelial invagination and tubular structure formation, signifying their potentials for tissue regeneration. Oral epithelial stem cells have been used in regenerative medicine over 1 decade. They are able to form a stratified cell sheet under three-dimensional culture conditions. Both experimental and clinical data indicate that the cell sheets can not only safely and effectively reconstruct the damaged cornea in humans, but also repair esophageal ulcer in animal models. Oral MSCs include dental pulp stem cells (DPSCs, stem cells from exfoliated deciduous teeth (SHED, stem cells from apical papilla (SCAP, periodontal ligament stem cells (PDLSCs, and mesenchymal stem cells from gingiva (GMSCs. They are widely applied in both regenerative dentistry and medicine. DPSCs, SHED, and SCAP are able to form dentin–pulp complex when being transplanted into immunodeficient animals. They have been experimentally used for the regeneration of dental pulp, neuron, bone muscle and blood vessels in animal models and have shown promising results. PDLSCs and GMSCs are demonstrated to be ideal cell sources for repairing the damaged tissues of periodontal, muscle, and tendon. Despite the abovementioned applications of oral stem cells, only a few human clinical trials are now underway to use them for the treatment of certain diseases. Since clinical use is the end goal, their true regenerative power and safety need to be further examined.Keywords: oral mesenchymal stem cells, oral

[Progress in stem cells and regenerative medicine].

Science.gov (United States)

Wang, Libin; Zhu, He; Hao, Jie; Zhou, Qi

2015-06-01

Stem cells have the ability to differentiate into all types of cells in the body and therefore have great application potential in regenerative medicine, in vitro disease modelling and drug screening. In recent years, stem cell technology has made great progress, and induced pluripotent stem cell technology revolutionizes the whole stem cell field. At the same time, stem cell research in our country has also achieved great progress and becomes an indispensable power in the worldwide stem cell research field. This review mainly focuses on the research progress in stem cells and regenerative medicine in our country since the advent of induced pluripotent stem cell technology, including induced pluripotent stem cells, transdifferentiation, haploid stem cells, and new gene editing tools.

Hydrogen-Oxygen PEM Regenerative Fuel Cell Development at the NASA Glenn Research Center

Science.gov (United States)

Bents, David J.; Scullin, Vincent J.; Chang, Bei-Jiann; Johnson, Donald W.; Garcia, Christoher P.; Jakupca, Ian J.

2005-01-01

The closed-cycle hydrogen-oxygen PEM regenerative fuel cell (RFC) at the NASA Glenn Research Center has successfully demonstrated closed cycle operation at rated power for multiple charge-discharge cycles. During charge cycle the RFC has absorbed input electrical power simulating a solar day cycle ranging from zero to 15 kWe peak, and delivered steady 5 kWe output power for periods exceeding 8 hr. Orderly transitions from charge to discharge mode, and return to charging after full discharge, have been accomplished without incident. Continuing test operations focus on: (1) Increasing the number of contiguous uninterrupted charge discharge cycles; (2) Increasing the performance envelope boundaries; (3) Operating the RFC as an energy storage device on a regular basis; (4) Gaining operational experience leading to development of fully automated operation; and (5) Developing instrumentation and in situ fluid sampling strategies to monitor health and anticipate breakdowns.

The imperative for regenerative agriculture.

Science.gov (United States)

Rhodes, Christopher J

2017-03-01

A review is made of the current state of agriculture, emphasising issues of soil erosion and dependence on fossil fuels, in regard to achieving food security for a relentlessly enlarging global population. Soil has been described as "the fragile, living skin of the Earth", and yet both its aliveness and fragility have all too often been ignored in the expansion of agriculture across the face of the globe. Since it is a pivotal component in a global nexus of soil-water-air-energy, how we treat the soil can impact massively on climate change - with either beneficial or detrimental consequences, depending on whether the soil is preserved or degraded. Regenerative agriculture has at its core the intention to improve the health of soil or to restore highly degraded soil, which symbiotically enhances the quality of water, vegetation and land-productivity. By using methods of regenerative agriculture, it is possible not only to increase the amount of soil organic carbon (SOC) in existing soils, but to build new soil. This has the effect of drawing down carbon from the atmosphere, while simultaneously improving soil structure and soil health, soil fertility and crop yields, water retention and aquifer recharge - thus ameliorating both flooding and drought, and also the erosion of further soil, since runoff is reduced. Since food production on a more local scale is found to preserve the soil and its quality, urban food production should be seen as a significant potential contributor to regenerative agriculture in the future, so long as the methods employed are themselves 'regenerative'. If localisation is to become a dominant strategy for dealing with a vastly reduced use of fossil fuels, and preserving soil quality - with increased food production in towns and cities - it will be necessary to incorporate integrated ('systems') design approaches such as permaculture and the circular economy (which minimise and repurpose 'waste') within the existing urban infrastructure. In

Carbon nanotube torsional springs for regenerative braking systems

International Nuclear Information System (INIS)

Liu, Sanwei; Martin, Corbin; Livermore, Carol; Lashmore, David; Schauer, Mark

2015-01-01

The modeling and demonstration of large stroke, high energy density and high power density torsional springs based on carbon nanotube (CNT) yarns is reported, as well as their application as energy-storing actuators for regenerative braking systems. An originally untwisted CNT yarn is cyclically loaded and unloaded in torsion, with the maximum rotation angle increasing incrementally until failure. The measured average extractable energy density values are 2.9 kJ kg −1   ±  1.2 kJ kg −1 and 3.4 kJ kg −1   ±  0.4 kJ kg −1 for 1-ply CNT yarns and 2-ply CNT yarns, respectively. Additionally, a regenerative braking system is demonstrated to capture the kinetic energy of a wheel and store it as elastic energy in twisted CNT yarns. When the yarn’s twist is released, the stored energy reaccelerates the wheel. The measured energy and mean power densities of the CNT yarns in the simple regenerative braking setup are on average 3.3 kJ kg −1 and 0.67 kW kg −1 , respectively, with maximum measured values of up to 4.7 kJ kg −1 and 1.2 kW kg −1 , respectively. A slightly lower energy density of up to 1.2 kJ kg −1 and a 0.29 kW kg −1 mean power density are measured for CNT yarns in a more complex setup that mimics a unidirectional rotating regenerative braking mechanism. (paper)

New evaluation methodology of regenerative braking contribution to energy efficiency improvement of electric vehicles

International Nuclear Information System (INIS)

Qiu, Chengqun; Wang, Guolin

2016-01-01

Highlights: • Two different contribution ratio evaluation parameters according to the deceleration braking process are proposed. • Methodologies for calculating the contribution made by regenerative brake to improve vehicle energy efficiency are proposed. • Road test results imply that the proposed parameters are effective. - Abstract: Comprehensive research is conducted on the design and control of a regenerative braking system for electric vehicles. The mechanism and evaluation methods of contribution brought by regenerative braking to improve electric vehicle’s energy efficiency are discussed and analyzed by the energy flow. Methodologies for calculating the contribution made by regenerative brake are proposed. Additionally a new regenerative braking control strategy called “serial 2 control strategy” is introduced. Moreover, two control strategies called “parallel control strategy” and “serial 1 control strategy” are proposed as the comparative control strategy. Furthermore, two different contribution ratio evaluation parameters according to the deceleration braking process are proposed. Finally, road tests are carried out under China typical city regenerative driving cycle standard with three different control strategies. The serial 2 control strategy offers considerably higher regeneration efficiency than the parallel strategy and serial 1 strategy.

Vibration control of an energy regenerative seat suspension with variable external resistance

Science.gov (United States)

Ning, Donghong; Sun, Shuaishuai; Du, Haiping; Li, Weihua; Zhang, Nong

2018-06-01

In this paper, an energy regenerative seat suspension with a variable external resistance is proposed and built, and a semi-active controller for its vibration control is also designed and validated. The energy regenerative seat suspension is built with a three-phase generator and a gear reducer, which are installed in the scissors structure centre of the seat suspension, and the vibration energy is directly harvested from the rotary movement of suspension's scissors structure. The electromagnetic torque of the semi-active seat suspension actuator is controlled by an external variable resistor. An integrated model including the seat suspension's kinematics and the generator is built and proven to match the test result very well. A simplified experimental phenomenon model is also built based on the test results for the controller design. A state feedback H∞ controller is proposed for the regenerative seat suspension's semi-active vibration control. The proposed regenerative seat suspension and its controller are validated with both simulations and experiments. A well-tuned passive seat suspension is applied to evaluate the regenerative seat's performance. Based on ISO 2631-1, the frequency-weighted root mean square (FW-RMS) acceleration of the proposed seat suspension has a 22.84% reduction when compared with the passive one, which indicates the improvement of ride comfort. At the same time, the generated RMS power is 1.21 W. The proposed regenerative seat suspension can greatly improve the driver's ride comfort and has the potential to be developed to a self-powered semi-active system.

Surgical Non-Regenerative Treatments for Peri-Implantitis: a Systematic Review

Directory of Open Access Journals (Sweden)

Ausra Ramanauskaite

2016-09-01

Full Text Available Objectives: The purposes of the present study were 1 to systematically review the literature on the surgical non-regenerative treatments of peri-implantitis and 2 to determine a predictable therapeutic option for the clinical management of peri-implantitis lesions. Material and Methods: The study search was performed on primary database MEDLINE and EMBASE from 2005 until 2016. Sequential screenings at the title, abstract, and full-text levels were performed. Clinical human studies in the English language that had reported changes in probing depth (PD and/or bleeding on probing (BOP and/or radiologic marginal bone level changes after peri-implantitis surgical non-regenerative treatment at 6-month follow-up or longer were included accordingly PRISMA guidelines. Results: The first electronic and hand search resulted in 765 citations. From 16 full-text articles reviewed, 6 were included in this systematic review. Surgical non-regenerative methods were found to be efficient in reducing clinical parameters. BOP and PD values were significantly decreased following implantoplasty and systematic administration of antibacterials, but not after local application of chemical compounds or diode laser. Similarly, significant improvement in clinical and radiographic parameters was found only after implantoplasty compared with resective surgery alone. We found significant heterogeneity in study designs and treatments provided among the pooled studies. All of the studies revealed an unclear or high risk of bias. Conclusions: Surgical non-regenerative treatment of peri-implantitis was found to be effective to reduce the soft tissue inflammation and decrease probing depth. More randomized controlled clinical trials are needed to assess the efficacy of surgical non-regenerative therapy of peri-implantitis.

Regenerative memory in time-delayed neuromorphic photonic resonators

Science.gov (United States)

Romeira, B.; Avó, R.; Figueiredo, José M. L.; Barland, S.; Javaloyes, J.

2016-01-01

We investigate a photonic regenerative memory based upon a neuromorphic oscillator with a delayed self-feedback (autaptic) connection. We disclose the existence of a unique temporal response characteristic of localized structures enabling an ideal support for bits in an optical buffer memory for storage and reshaping of data information. We link our experimental implementation, based upon a nanoscale nonlinear resonant tunneling diode driving a laser, to the paradigm of neuronal activity, the FitzHugh-Nagumo model with delayed feedback. This proof-of-concept photonic regenerative memory might constitute a building block for a new class of neuron-inspired photonic memories that can handle high bit-rate optical signals.

Solar Energy in the Nineteen Eighties

International Nuclear Information System (INIS)

Broda, E.

1979-01-01

Solar energy is abundant inexhaustible and nonpolluting. Its utilization does not affect the climate, and it does not lend itself to military applications. The solar-thermal, solar-electric and solar-chemical options are available. The production of low-temperature heat for warm water and for space heating, of enormous importance in the energy budget, is economic already now in many situations. Technical progress is still considerable. With the further rise in fuel prices the application will increase dramatically. Use of solar heat for large-scale generation of electricity, i.e. of power on the basis of the solar-thermal option, should be approached cautiously. Possibilities include the tower concept and ocean thermal-electric conversion (OTEC). Investment would be large, and the technology hard. Better long-term chances may be given, for decentralized application in developing countries, to the farm concept. In contrast, the chances for cheap small-scale, and later large-scale, use of solar semiconductor cells (solar-electric option) are most favourable. Technical progress is rapid, and prices drop precipitously. For the production of fuel, the solar-chemical option is in the foreground. Gaseous, liquid and convenient solid fuels can be obtained from biomass, especially by fermentation. At the moment, biogenic wastes are already available in relatively large amounts. Subsequently, energy farming is to be introduced. Biomass converted to hydrogen can be employed for production of electricity by means of fuel cells. In the more distant future, hydrogen is to be made abiotically by photolysis of water, and is to be introduced into a hydrogen economy. Probably the technology will be based on the application of synthetic membranes. It is possible that regenerative solar energy in all its forms can in the end replace all existing energy used by man. This substitution will s however, be a gradual process. (author)

Regulators of pluripotency and their implications in regenerative medicine

Directory of Open Access Journals (Sweden)

El-Badawy A

2015-04-01

Full Text Available Ahmed El-Badawy, Nagwa El-Badri Center of Excellence for Stem Cells and Regenerative Medicine, Zewail City of Science and Technology, Giza, Egypt Abstract: The ultimate goal of regenerative medicine is to replace damaged tissues with new functioning ones. This can potentially be accomplished by stem cell transplantation. While stem cell transplantation for blood diseases has been increasingly successful, widespread application of stem cell therapy in the clinic has shown limited results. Despite successful efforts to refine existing methodologies and to develop better ones for reprogramming, clinical application of stem cell therapy suffers from issues related to the safety of the transplanted cells, as well as the low efficiency of reprogramming technology. Better understanding of the underlying mechanism(s involved in pluripotency should accelerate the clinical application of stem cell transplantation for regenerative purposes. This review outlines the main decision-making factors involved in pluripotency, focusing on the role of microRNAs, epigenetic modification, signaling pathways, and toll-like receptors. Of special interest is the role of toll-like receptors in pluripotency, where emerging data indicate that the innate immune system plays a vital role in reprogramming. Based on these data, we propose that nongenetic mechanisms for reprogramming provide a novel and perhaps an essential strategy to accelerate application of regenerative medicine in the clinic. Keywords: dedifferentiation, transdifferentiation, reprogramming, pluripotency, microRNAs, epigenetic modifications, signaling pathways, toll-like receptors

Nanotechnology and regenerative therapeutics in plastic surgery: The next frontier.

Science.gov (United States)

Tan, Aaron; Chawla, Reema; G, Natasha; Mahdibeiraghdar, Sara; Jeyaraj, Rebecca; Rajadas, Jayakumar; Hamblin, Michael R; Seifalian, Alexander M

2016-01-01

The rapid ascent of nanotechnology and regenerative therapeutics as applied to medicine and surgery has seen an exponential rise in the scale of research generated in this field. This is evidenced not only by the sheer volume of papers dedicated to nanotechnology but also in a large number of new journals dedicated to nanotechnology and regenerative therapeutics specifically to medicine and surgery. Aspects of nanotechnology that have already brought benefits to these areas include advanced drug delivery platforms, molecular imaging and materials engineering for surgical implants. Particular areas of interest include nerve regeneration, burns and wound care, artificial skin with nanoelectronic sensors and head and neck surgery. This study presents a review of nanotechnology and regenerative therapeutics, with focus on its applications and implications in plastic surgery. Copyright © 2015 British Association of Plastic, Reconstructive and Aesthetic Surgeons. All rights reserved.

Advanced regenerative heat recovery system

Science.gov (United States)

Prasad, A.; Jasti, J. K.

1982-02-01

A regenerative heat recovery system was designed and fabricated to deliver 1500 scfm preheated air to a maximum temperature of 1600 F. Since this system is operating at 2000 F, the internal parts were designed to be fabricated with ceramic materials. This system is also designed to be adaptable to an internal metallic structure to operate in the range of 1100 to 1500 F. A test facility was designed and fabricated to test this system. The test facility is equipped to impose a pressure differential of up to 27 inches of water column in between preheated air and flue gas lines for checking possible leakage through the seals. The preliminary tests conducted on the advanced regenerative heat recovery system indicate the thermal effectiveness in the range of 60% to 70%. Bench scale studies were conducted on various ceramic and gasket materials to identify the proper material to be used in high temperature applications. A market survey was conducted to identify the application areas for this heat recovery system. A cost/benefit analysis showed a payback period of less than one and a half years.

Nonlinear Modeling and Coordinate Optimization of a Semi-Active Energy Regenerative Suspension with an Electro-Hydraulic Actuator

Directory of Open Access Journals (Sweden)

Farong Kou

2018-01-01

Full Text Available In order to coordinate the damping performance and energy regenerative performance of energy regenerative suspension, this paper proposes a structure of a vehicle semi-active energy regenerative suspension with an electro-hydraulic actuator (EHA. In light of the proposed concept, a specific energy regenerative scheme is designed and a mechanical properties test is carried out. Based on the test results, the parameter identification for the system model is conducted using a recursive least squares algorithm. On the basis of the system principle, the nonlinear model of the semi-active energy regenerative suspension with an EHA is built. Meanwhile, linear-quadratic-Gaussian control strategy of the system is designed. Then, the influence of the main parameters of the EHA on the damping performance and energy regenerative performance of the suspension is analyzed. Finally, the main parameters of the EHA are optimized via the genetic algorithm. The test results show that when a sinusoidal is input at the frequency of 2 Hz and the amplitude of 30 mm, the spring mass acceleration root meam square value of the optimized EHA semi-active energy regenerative suspension is reduced by 22.23% and the energy regenerative power RMS value is increased by 40.51%, which means that while meeting the requirements of vehicle ride comfort and driving safety, the energy regenerative performance is improved significantly.

Thermo-economic optimization of Regenerative Organic Rankine Cycle for waste heat recovery applications

International Nuclear Information System (INIS)

Imran, Muhammad; Park, Byung Sik; Kim, Hyouck Ju; Lee, Dong Hyun; Usman, Muhammad; Heo, Manki

2014-01-01

Highlights: • Thermo-economic optimization of regenerative ORC is performed. • Optimization is performed using multi objective genetic algorithm. • Objective function is maximum cycle efficiency and minimum specific investment. • Evaporation pressure, pinch point and superheat are decision variables. • Sensitivity analysis is performed to investigate effect of decision variables. - Abstract: Organic Rankine Cycle (ORC) is low grade and waste heat conversion technology. The current article deal with the thermo-economic optimization of basic ORC and regenerative ORC for waste heat recovery applications under constant heat source condition. Thermal efficiency and specific investment cost of basic ORC, single stage regenerative and double stage regenerative ORC has been optimized by using Non-dominated Sorting Genetic Algorithm-II (NSGA-II). Maximum thermal efficiency and minimum specific investment cost were selected as objective functions and relative increase in thermal efficiency and cost has been analyzed taking the basic ORC as base case. The constraint set consist of evaporation pressure, superheat, pinch point temperature difference in evaporator and condenser. The optimization was performed for five different working fluids. The optimization result show that R245fa is best working under considered conditions and basic ORC has low specific investment cost and thermal efficiency compared to regenerative ORC. R245fa is low boiling organic fluid, which has high degree of thermal stability and compatible with common construction materials of ORC. The average increase in thermal efficiency from basic ORC to single stage regenerative ORC was 1.01% with an additional cost of 187 $/kW while from basic ORC to double stage regenerative ORC was 1.45% with an average increase in cost of 297 $/kW. The sensitivity analysis was also performed to investigate the effect of operating conditions which show that evaporation pressure has promising effect on thermal

Device for processing regenerative wastes of ion exchange resin

International Nuclear Information System (INIS)

Kuroda, Osamu; Ebara, Katsuya; Shindo, Toshikazu; Takahashi, Sankichi

1986-01-01

Purpose: To facilitate the operation and maintenance of a processing device by dividing radioactive wastes produced in the regenerative process of ion exchange resin into a regenerated usable recovery liquid and wastes. Constitution: Sulfuric acid is recovered by a diffusion dialysis method from wastes containing sulfuric acid that are generated in the regenerative process of cation-exchange resin and also caustic soda is recovered by the diffusion dialysis method from wastes containing caustic soda that are generated in the regenerative process of anion-exchange resin. The sulfuric acid and caustic soda thus recovered are used for the regeneration of ion-exchange resin. A concentrator is provided for concentrating the sulfuric acid and caustic soda water solution to concentration suitable for the regeneration of these ion-exchange resins. Also provided is a recovery device for recovering water generated from the concentrator. This device is of so simple a constitution that its operation and maintenance can be performed very easily, thereby greatly reducing the quantity of waste liquid required to be stored in drums. (Takahashi, M.)

Regenerative Medicine Applications in Wound Care.

Science.gov (United States)

Nilforoushzadeh, Mohammad Ali; Sisakht, Mahsa Mollapour; Seifalian, Alexander Marcus; Amirkhani, Mohammad Amir; Banafshe, Hamid Reza; Verdi, Javad; Sharifzad, Farzaneh; Taghiabadi, Ehsan

2017-01-01

During the last two decades, a number of studies have been carried out on the application of regenerative medicine in the field of dermatology. The aim of this research was to critically review the application of regenerative medicine in the field of dermatology. The next aim was to look in depth to see whether regenerative medicine strategies have a place in the future of wound healing in a clinical setting. More specifically, to see if these strategies would apply for burns and non-healing diabetic wounds. Billions of dollars have been spent worldwide on research in wound treatment and skin regeneration. Although a high number of clinical trials show promising results, there is still no commercially available treatment for use. In addition, the outcome data from the clinical trials, taking place throughout the world, are not published in a standardized manner. Standardization within clinical trials is required for: protocols, outcome, endpoint values, and length of follow-up. The lack of standardization makes it much more difficult to compare the data collected and the different types of treatment. Despite several promising results from research and early phase clinical studies, the treatment for wounds as well as skin regeneration is still considered as an unmet clinical need. However, in the past three years, more promising research has been approaching clinical trials; this could be the solution that clinicians have been waiting for. This is a multibillion dollar industry for which there should be enough incentive for researchers and industry to seek the solution. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Accelerating regenerative medicine: the Japanese experiment in ethics and regulation.

Science.gov (United States)

Lysaght, Tamra

2017-09-01

In 2014, the Japanese National Diet introduced new laws aimed at promoting the clinical translation of stem cells and regenerative medicine. The basic action of these laws is to allow the early introduction of regenerative medicine products into the Japanese market through an accelerated approval process, while providing patients with access to certain types of stem cell and cell-based therapies in the context of private clinical practice. While this framework appears to offer enormous opportunities for the translation of stem cell science, it raises ethical challenges that have not yet been fully explored. This paper critically analyzes this framework with respect to the prioritization of safety over clinical benefit, distributive justice and public trust in science and medicine. It is argued that the framework unfairly burdens patients and strained healthcare systems without any clear benefits, and may undermine the credibility of the regenerative medicine field as it emerges.

Developing a pro-regenerative biomaterial scaffold microenvironment requires T helper 2 cells.

Science.gov (United States)

Sadtler, Kaitlyn; Estrellas, Kenneth; Allen, Brian W; Wolf, Matthew T; Fan, Hongni; Tam, Ada J; Patel, Chirag H; Luber, Brandon S; Wang, Hao; Wagner, Kathryn R; Powell, Jonathan D; Housseau, Franck; Pardoll, Drew M; Elisseeff, Jennifer H

2016-04-15

Immune-mediated tissue regeneration driven by a biomaterial scaffold is emerging as an innovative regenerative strategy to repair damaged tissues. We investigated how biomaterial scaffolds shape the immune microenvironment in traumatic muscle wounds to improve tissue regeneration. The scaffolds induced a pro-regenerative response, characterized by an mTOR/Rictor-dependent T helper 2 pathway that guides interleukin-4-dependent macrophage polarization, which is critical for functional muscle recovery. Manipulating the adaptive immune system using biomaterials engineering may support the development of therapies that promote both systemic and local pro-regenerative immune responses, ultimately stimulating tissue repair. Copyright © 2016, American Association for the Advancement of Science.

Adipose-derived mesenchymal stem cells and regenerative medicine.

Science.gov (United States)

Konno, Masamitsu; Hamabe, Atsushi; Hasegawa, Shinichiro; Ogawa, Hisataka; Fukusumi, Takahito; Nishikawa, Shimpei; Ohta, Katsuya; Kano, Yoshihiro; Ozaki, Miyuki; Noguchi, Yuko; Sakai, Daisuke; Kudoh, Toshihiro; Kawamoto, Koichi; Eguchi, Hidetoshi; Satoh, Taroh; Tanemura, Masahiro; Nagano, Hiroaki; Doki, Yuichiro; Mori, Masaki; Ishii, Hideshi

2013-04-01

Adipose tissue-derived mesenchymal stem cells (ADSCs) are multipotent and can differentiate into various cell types, including osteocytes, adipocytes, neural cells, vascular endothelial cells, cardiomyocytes, pancreatic β-cells, and hepatocytes. Compared with the extraction of other stem cells such as bone marrow-derived mesenchymal stem cells (BMSCs), that of ADSCs requires minimally invasive techniques. In the field of regenerative medicine, the use of autologous cells is preferable to embryonic stem cells or induced pluripotent stem cells. Therefore, ADSCs are a useful resource for drug screening and regenerative medicine. Here we present the methods and mechanisms underlying the induction of multilineage cells from ADSCs. © 2013 The Authors Development, Growth & Differentiation © 2013 Japanese Society of Developmental Biologists.

Regenerative Endodontic Treatment of a Maxillary Mature Premolar

Directory of Open Access Journals (Sweden)

Qingan Xu

2018-01-01

Full Text Available Regenerative endodontic treatment was performed on a mature maxillary premolar diagnosed as chronic pulpitis. The root canals were chemomechanically prepared and placed intracanal medicaments at the first appointment. Then 2 weeks later, a blood clot was created in the canals, over which mineral trioxide aggregate was placed. At 6-month follow-up, cementum-like tissue seemed to be formed in the root canal along with nearly recovered pulp vitality. At 12-month recall, the radiographic results revealed evidence of root wall thickening. At 30-month recall, no periapical lesion was found. This case report indicates that regenerative endodontic treatment for the mature premolar is feasible. More cases are needed for further validation.

Recommendations for using regenerative endodontic procedures in permanent immature traumatized teeth.

Science.gov (United States)

Garcia-Godoy, Franklin; Murray, Peter E

2012-02-01

The regeneration of immature permanent teeth following trauma could be beneficial to reduce the risk of fracture and loss of millions of teeth each year. Regenerative endodontic procedures include revascularization, partial pulpotomy, and apexogenesis. Several case reports give these procedures a good prognosis as an alternative to apexification. Care is needed to deliver regenerative endodontic procedures that maintain or restore the vitality of teeth, but which also disinfect and remove necrotic tissues. Regeneration can be accomplished through the activity of the cells from the pulp, periodontium, vascular, and immune system. Most therapies use the host's own pulp or vascular cells for regeneration, but other types of dental stem cell therapies are under development. There are no standardized treatment protocols for endodontic regeneration. The purpose of this article is to review the recent literature and suggest guidelines for using regenerative endodontic procedures for the treatment of permanent immature traumatized teeth. Recommendations for the selection of regenerative and conventional procedures based on the type of tooth injury, fracture type, presence of necrosis or infection, periodontal status, presence of periapical lesions, stage of tooth development, vitality status, patient age, and patient health status will be reviewed. Because of the lack of long-term evidence to support the use of regenerative endodontic procedures in traumatized teeth with open apices, revascularization regeneration procedures should only be attempted if the tooth is not suitable for root canal obturation, and after apexogenesis, apexification, or partial pulpotomy treatments have already been attempted and have a poor prognosis. © 2011 John Wiley & Sons A/S.

Maximum Safety Regenerative Power Tracking for DC Traction Power Systems

Directory of Open Access Journals (Sweden)

Guifu Du

2017-02-01

Full Text Available Direct current (DC traction power systems are widely used in metro transport systems, with running rails usually being used as return conductors. When traction current flows through the running rails, a potential voltage known as “rail potential” is generated between the rails and ground. Currently, abnormal rises of rail potential exist in many railway lines during the operation of railway systems. Excessively high rail potentials pose a threat to human life and to devices connected to the rails. In this paper, the effect of regenerative power distribution on rail potential is analyzed. Maximum safety regenerative power tracking is proposed for the control of maximum absolute rail potential and energy consumption during the operation of DC traction power systems. The dwell time of multiple trains at each station and the trigger voltage of the regenerative energy absorbing device (READ are optimized based on an improved particle swarm optimization (PSO algorithm to manage the distribution of regenerative power. In this way, the maximum absolute rail potential and energy consumption of DC traction power systems can be reduced. The operation data of Guangzhou Metro Line 2 are used in the simulations, and the results show that the scheme can reduce the maximum absolute rail potential and energy consumption effectively and guarantee the safety in energy saving of DC traction power systems.

An animal model to study regenerative endodontics.

Science.gov (United States)

Torabinejad, Mahmoud; Corr, Robert; Buhrley, Matthew; Wright, Kenneth; Shabahang, Shahrokh

2011-02-01

A growing body of evidence is demonstrating the possibility for regeneration of tissues within the pulp space and continued root development in teeth with necrotic pulps and open apices. There are areas of research related to regenerative endodontics that need to be investigated in an animal model. The purpose of this study was to investigate ferret cuspid teeth as a model to investigate factors involved in regenerative endodontics. Six young male ferrets between the ages of 36-133 days were used in this investigation. Each animal was anesthetized and perfused with 10% buffered formalin. Block sections including the mandibular and maxillary cuspid teeth and their surrounding periapical tissues were obtained, radiographed, decalcified, sectioned, and stained with hematoxylin-eosin to determine various stages of apical closure in these teeth. The permanent mandibular and maxillary cuspid teeth with open apices erupted approximately 50 days after birth. Initial signs of closure of the apical foramen in these teeth were observed between 90-110 days. Complete apical closure was observed in the cuspid teeth when the animals were 133 days old. Based on the experiment, ferret cuspid teeth can be used to investigate various factors involved in regenerative endodontics that cannot be tested in human subjects. The most appropriate time to conduct the experiments would be when the ferrets are between the ages of 50 and 90 days. Copyright © 2011. Published by Elsevier Inc.

Regenerative laser system

International Nuclear Information System (INIS)

Biancardi, F.R.; Landerman, A.; Melikian, G.

1975-01-01

Regenerative apparatus for exhausting the working medium from the optical cavity of a laser and for supplying preheated diluent to the reaction chamber of a laser is disclosed. In an aftercooler thermal energy is exchanged between the working medium exhausted from the optical cavity and a cryogenic coolant which is subsequently utilized as the motive fluid for an ejector and as a diluent in the production of laser gas. Highly toxic and corrosive gases are condensed out of the working medium as the cryogenic coolant is evaporated and superheated. A preheater transfers additional heat to the diluent before the diluent enters the reaction chamber. (U.S.)

Regenerative endodontics and tissue engineering: what the future holds?

Science.gov (United States)

Goodis, Harold E; Kinaia, Bassam Michael; Kinaia, Atheel M; Chogle, Sami M A

2012-07-01

The work performed by researchers in regenerative endodontics and tissue engineering over the last decades has been superb; however, many questions remain to be answered. The basic biologic mechanisms must be elucidated that will allow the development of dental pulp and dentin in situ. Stress must be placed on the many questions that will lead to the design of effective, safe treatment options and therapies. This article discusses those questions, the answers to which may become the future of regenerative endodontics. The future remains bright, but proper support and patience are required. Copyright © 2012 Elsevier Inc. All rights reserved.

Stem cells and the future of regenerative medicine

National Research Council Canada - National Science Library

National Research Council, Committee on the Biological and Biomedical Applications of Stem Cell Research; Commission on Life Sciences; National Research Council; Board on Life Sciences; Board on Neuroscience and Behavioral Health; Division on Earth and Life Studies; Institute of Medicine

2002-01-01

.... Stem Cells and the Future of Regenerative Medicine provides a deeper exploration of the biological, ethical, and funding questions prompted by the therapeutic potential of undifferentiated human cells...

Modelling and analysis of a desiccant cooling system using the regenerative indirect evaporative cooling process

DEFF Research Database (Denmark)

Bellemo, Lorenzo; Elmegaard, Brian; Reinholdt, Lars O.

2013-01-01

This paper focuses on the numerical modeling and analysis of a Desiccant Cooling (DEC) system with regenerative indirect evaporative cooling, termed Desiccant Dewpoint Cooling (DDC) system. The DDC system includes a Desiccant Wheel (DW), Dew Point Coolers (DPCs), a heat recovery unit and a heat...... in different climates: temperate in Copenhagen and Mediterranean in Venice. Cheap and clean heat sources (e.g. solar energy) strongly increase the attractiveness of the DDC system. For the Mediterranean climate the DDC system represents a convenient alternative to chiller-based systems in terms of energy costs...... and CO2 emissions. The electricity consumption for auxiliaries in the DDC system is higher than in the chiller-based systems. The number of commercial-size DPC units required to cover the cooling load during the whole period is high: 8 in Copenhagen and 12 in Venice....

Optimization of the alignment sensitivity and energy stability of the NIF regenerative amplifier cavity

International Nuclear Information System (INIS)

Hopps, N. W.

1998-01-01

The work to improve the energy stability of the regenerative amplifier ('regen') for the National Ignition Facility is described. This includes a fast feed-forward system, designed to regulate the output energy of the regen by monitoring how quickly a pulse builds up over many round trips. Shot-to-shot energy fluctuations of all elements prior to (and including) the regen may be compensated for in this way, at the expense of a loss of approximately 50%. Also included is a detailed study into the alignment sensitivity of the regen cavity, with the goal of quantifying the effect of misalignment on the output energy. This is done by calculating the displacement of the eigenmode by augmenting the cavity ABCD matrix with the misalignment matrix elements, E, F. In this way, cavity misalignment issues due to thermal loading of the gain medium are investigated. Alternative cavity designs, which reduce the alignment sensitivity and therefore the energy drift over periods of continuous operation, are considered. Alterations to the amplifier head design are also considered

Adaptation and validation of the REGEN expert system for the Central Appalachians

Science.gov (United States)

Lance A. Vickers; Thomas R. Fox; David L. Loftis; David A. Boucugnani

2011-01-01

REGEN is an expert system that predicts future species composition at the onset of stem exclusion using preharvest stand conditions. To extend coverage into hardwood stands of the Central Appalachians, we developed REGEN knowledge bases for four site qualities (xeric, subxeric, submesic, mesic) based on relevant literature and expert opinion. Data were collected from...

Predicting Forest Regeneration in the Central Appalachians Using the REGEN Expert System

Science.gov (United States)

Lance A. Vickers; Thomas R. Fox; David L. Loftis; David A. Boucugnani

2011-01-01

REGEN is an expert system designed by David Loftis to predict the future species composition of dominant and codominant stems in forest stands at the onset of stem exclusion following a proposed harvest. REGEN predictions are generated using competitive rankings for advance reproduction along with other existing stand conditions. These parameters are contained within...

Exploiting the Bioactive Properties of the Dentin-Pulp Complex in Regenerative Endodontics.

Science.gov (United States)

Smith, Anthony J; Duncan, Henry F; Diogenes, Anibal; Simon, Stephane; Cooper, Paul R

2016-01-01

The development of regenerative endodontic therapies offers exciting opportunities for future improvements in treatment outcomes. Advances in our understanding of regenerative events at the molecular and cellular levels are helping to underpin development of these therapies, although the various strategies differ in the translational challenges they pose. The identification of a variety of bioactive molecules, including growth factors, cytokines, chemokines, and matrix molecules, sequestered within dentin and dental pulp provides the opportunity to present key signaling molecules promoting reparative and regenerative events after injury. The protection of the biological activity of these molecules by mineral in dentin before their release allows a continuing supply of these molecules, while avoiding the short half-life and the non-human origin of exogenous molecules. The ready release of these bioactive molecules by the various tissue preparation agents, medicaments, and materials commonly used in endodontics highlights the opportunities for translational regenerative strategies exploiting these molecules with little change to existing clinical practice. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Enhanced Regenerative Braking Strategies for Electric Vehicles: Dynamic Performance and Potential Analysis

Directory of Open Access Journals (Sweden)

Boyi Xiao

2017-11-01

Full Text Available A regenerative braking system and hydraulic braking system are used in conjunction in the majority of electric vehicles worldwide. We propose a new regenerative braking distribution strategy that is based on multi-input fuzzy control logic while considering the influences of the battery’s state of charge, the brake strength and the motor speed. To verify the braking performance and recovery economy, this strategy was applied to a battery electric vehicle model and compared with two other improved regenerative braking strategies. The performance simulation was performed using standard driving cycles (NEDC, LA92, and JP1015 and a real-world-based urban cycle in China. The tested braking strategies satisfied the general safety requirements of Europe (as specified in ECE-13H, and the emergency braking scenario and economic potential were tested. The simulation results demonstrated the differences in the braking force distribution performance of these three regenerative braking strategies, the feasibility of the braking methods for the proposed driving cycles and the energy economic potential of the three strategies.

Regenerative endodontics: a true paradigm shift or a bandwagon about to be derailed?

Science.gov (United States)

Nazzal, H; Duggal, M S

2017-02-01

Regenerative endodontic techniques (RETs) have been hailed as a paradigm shift for the management of traumatised non-vital immature permanent anterior teeth. In this article the aim was to critically appraise the literature with regards to the outcome of regenerative endodontics on root development. Critical review of the literature where regenerative endodontic techniques have been used in the management of immature non-vital teeth with continuation of root development as the main outcome reported. Most studies published were in the form of case reports and series with very few randomised controlled trials with a high risk of bias. Continuation of root development following the use of RET has been shown to be unpredictable at best with lower success in those teeth losing vitality as a result of dental trauma. Despite the high success of regenerative endodontics in terms of periodontal healing including resolution of clinical and radiographic signs and symptoms of infection, continuation of root development remains an unpredictable outcome. The use of a blood clot as a scaffold in regenerative endodontics should be reviewed carefully as that might offer an environment for repair rather than regeneration. In addition, preservation of structures, such as Hertwig's epithelial root sheath, may have an important bearing on the success of this approach and should be further investigated.

Regenerative medicine in dental and oral tissues: Dental pulp mesenchymal stem cell

Directory of Open Access Journals (Sweden)

Janti Sudiono

2017-08-01

Full Text Available Background. Regenerative medicine is a new therapeutic modality using cell, stem cell and tissue engineering technologies. Purpose. To describe the regenerative capacity of dental pulp mesenchymal stem cell. Review. In dentistry, stem cell and tissue engineering technologies develop incredibly and attract great interest, due to the capacity to facilitate innovation in dental material and regeneration of dental and oral tissues. Mesenchymal stem cells derived from dental pulp, periodontal ligament and dental follicle, can be isolated, cultured and differentiated into various cells, so that can be useful for regeneration of dental, nerves, periodontal and bone tissues. Tissue engineering is a technology in reconstructive biology, which utilizes mechanical, cellular, or biological mediators to facilitate regeneration or reconstruction of a particular tissue. The multipotency, high proliferation rates and accessibility, make dental pulp as an attractive source of mesenchymal stem cells for tissue regeneration. Revitalized dental pulp and continued root development is the focus of regenerative endodontic while biological techniques that can restore lost alveolar bone, periodontal ligament, and root cementum is the focus of regenerative periodontic. Conclucion. Dentin-derived morphogens such as BMP are known to be involved in the regulation of odontogenesis. The multipotency and angiogenic capacity of DPSCs as the regenerative capacity of human dentin / pulp complex indicated that dental pulp may contain progenitors that are responsible for dentin repair. The human periodontal ligament is a viable alternative source for possible primitive precursors to be used in stem cell therapy.

Nanotechnologies in regenerative medicine

Czech Academy of Sciences Publication Activity Database

Kubinová, Šárka; Syková, Eva

2010-01-01

Roč. 19, 3-4 (2010), s. 144-156 ISSN 1364-5706 R&D Projects: GA AV ČR IAA500390902; GA MŠk(CZ) LC554; GA AV ČR KAN201110651 Grant - others:GA ČR(CZ) 1M0538; GA ČR(CZ) GA203/09/1242; GA AV ČR(CZ) KAN200520804; EC FP6 project ENIMET(XE) LSHM-CT-2005-019063 Program:1M; GA; KA Institutional research plan: CEZ:AV0Z50390703 Keywords : Nanotechnology * regenerative medicine * nanofibers Subject RIV: FH - Neurology Impact factor: 1.051, year: 2010

Regenerative medicine in Europe: global competition and innovation governance.

Science.gov (United States)

Hogarth, Stuart; Salter, Brian

2010-11-01

Leading European nations with strong biotech sectors, such as the UK and Germany, are investing heavily in regenerative medicine, seeking competitive advantage in this emerging sector. However, in the broader biopharmaceutical sector, the EU is outperformed by the USA on all metrics, reflecting longstanding problems: limited venture capital finance, a fragmented patent system, and relatively weak relations between academia and industry. The current global downturn has exacerbated these difficulties. The crisis comes at a time when the EU is reframing its approach to the governance of innovation and renewing its commitment to the goal of making Europe the leading player in the global knowledge economy. If the EU is to gain a competitive advantage in the regenerative medicine sector then it must coordinate a complex multilevel governance framework that encompasses the EU, member states and regional authorities. This article takes stock of Europe's current competitive position within the global bioeconomy, drawing on a variety of metrics in the three intersecting spheres of innovation governance: science, market and society. These data then provide a platform for reviewing the problems of innovation governance faced by the EU and the strategic choices that have to be confronted in the regenerative medicine sector.

Regenerative endodontics: A state of the art

Directory of Open Access Journals (Sweden)

Rashmi Bansal

2011-01-01

Full Text Available Scientific advances in the creation of restorative biomaterials, in vitro cell culture technology, tissue grafting, tissue engineering, molecular biology and the human genome project provide the basis for the introduction of new technologies into dentistry. Non-vital infected teeth have long been treated with root canal therapy (for mature root apex and apexification (for immature root apex, or doomed to extraction. Although successful, current treatments fail to re-establish healthy pulp tissue in these teeth. But, what if the non-vital tooth could be made vital once again? That is the hope offered by regenerative endodontics, an emerging field focused on replacing traumatized and diseased pulp with functional pulp tissue. Restoration of vitality of non-vital tooth is based on tissue engineering and revascularization procedures. The purpose of this article is to review these biological procedures and the hurdles that must be overcome to develop regenerative endodontic procedures.

Turning Regenerative Medicine Breakthrough Ideas and Innovations into Commercial Products.

Science.gov (United States)

Bayon, Yves; Vertès, Alain A; Ronfard, Vincent; Culme-Seymour, Emily; Mason, Chris; Stroemer, Paul; Najimi, Mustapha; Sokal, Etienne; Wilson, Clayton; Barone, Joe; Aras, Rahul; Chiesi, Andrea

2015-12-01

The TERMIS-Europe (EU) Industry committee intended to address the two main critical issues in the clinical/commercial translation of Advanced Therapeutic Medicine Products (ATMP): (1) entrepreneurial exploitation of breakthrough ideas and innovations, and (2) regulatory market approval. Since January 2012, more than 12,000 publications related to regenerative medicine and tissue engineering have been accepted for publications, reflecting the intense academic research activity in this field. The TERMIS-EU 2014 Industry Symposium provided a reflection on the management of innovation and technological breakthroughs in biotechnology first proposed to contextualize the key development milestones and constraints of allocation of financial resources, in the development life-cycle of radical innovation projects. This was illustrated with the biofuels story, sharing similarities with regenerative medicine. The transition was then ensured by an overview of the key identified challenges facing the commercialization of cell therapy products as ATMP examples. Real cases and testimonies were then provided by a palette of medical technologies and regenerative medicine companies from their commercial development of cell and gene therapy products. Although the commercial development of ATMP is still at the proof-of-concept stage due to technology risks, changing policies, changing markets, and management changes, the sector is highly dynamic with a number of explored therapeutic approaches, developed by using a large diversity of business models, both proposed by the experience, pitfalls, and successes of regenerative medicine pioneers, and adapted to the constraint resource allocation and environment in radical innovation projects.

Stem Cells in Regenerative Medicine

OpenAIRE

Sykova, Eva; Forostyak, Serhiy

2013-01-01

Background: A number of cardiovascular, neurological, musculoskeletal and other diseases have a limited capacity for repair and only a modest progress has been made in treatment of brain diseases. The discovery of stem cells has opened new possibilities for the treatment of these maladies, and cell therapy now stands at the cutting-edge of modern regenerative medicine and tissue engineering. Experimental data and the first clinical trials employing stem cells have shown their broad therapeuti...

Regenerative Snubber For GTO-Commutated SCR Inverter

Science.gov (United States)

Rippel, Wally E.; Edwards, Dean B.

1992-01-01

Proposed regenerative snubbing circuit substituted for dissipative snubbing circuit in inverter based on silicon controlled rectifiers (SCR's) commutated by gate-turn-off thyristor (GTO). Intended to reduce loss of power that occurs in dissipative snubber. Principal criteria in design: low cost, simplicity, and reliability.

On friction braking demand with regenerative braking

NARCIS (Netherlands)

Walker, A.M.; Lampérth, M.U.; Wilkins, S.

2002-01-01

Developments in Hybrid Electric and pure Electric Vehicles are intended to improve the operational efficiency of road vehicles. Regenerative braking, which has long been established in rail vehicles, is integral to efficiency improvement, with up to 30% of overall traction energy demand satisfied by

A novel regenerative shock absorber with a speed doubling mechanism and its Monte Carlo simulation

Science.gov (United States)

Zhang, Ran; Wang, Xu; Liu, Zhenwei

2018-03-01

A novel regenerative shock absorber has been designed and fabricated. The novelty of the presented work is the application of the double speed regenerative shock absorber that utilizes the rack and pinion mechanism to increase the magnet speed with respect to the coils for higher power output. The simulation models with parameters identified from finite element analysis and the experiments are developed. The proposed regenerative shock absorber is compared with the regenerative shock absorber without the rack and pinion mechanism, when they are integrated into the same quarter vehicle suspension system. The sinusoidal wave road profile displacement excitation and the random road profile displacement excitation with peak amplitude of 0.035 m are applied as the inputs in the frequency range of 0-25 Hz. It is found that with the sinusoidal and random road profile displacement input, the proposed innovative design can increase the output power by 4 times comparing to the baseline design. The proposed double speed regenerative shock absorber also presents to be more sensitive to the road profile irregularity than the single speed regenerative shock absorber as suggested by Monte Carlo simulation. Lastly the coil mass and amplification factor are studied for sensitivity analysis and performance optimization, which provides a general design method of the regenerative shock absorbers. It shows that for the system power output, the proposed design becomes more sensitive to either the coil mass or amplification factor depending on the amount of the coil mass. With the specifically selected combination of the coil mass and amplification factor, the optimized energy harvesting performance can be achieved.

Artificial organs versus regenerative medicine: is it true?

Science.gov (United States)

Nosé, Yukihiko; Okubo, Hisashi

2003-09-01

Individuals engaged in the fields of artificial kidney and artificial heart have often mistakenly stated that "the era of artificial organs is over; regenerative medicine is the future." Contrarily, we do not believe artificial organs and regenerative medicine are different medical technologies. As a matter of fact, artificial organs developed during the last 50 years have been used as a bridge to regeneration. The only difference between regenerative medicine and artificial organs is that artificial organs for the bridge to regeneration promote tissue regeneration in situ, instead of outside the body (for example, vascular prostheses, neuroprostheses, bladder substitutes, skin prostheses, bone prostheses, cartilage prostheses, ligament prostheses, etc.). All of these artificial organs are successful because tissue regeneration over a man-made prosthesis is established inside the patient's body (artificial organs to support regeneration). Another usage of the group of artificial organs for the bridge to regeneration is to sustain the functions of the patient's diseased organs during the regeneration process of the body's healthy tissues and/or organs. This particular group includes artificial kidney, hepatic assist, respiratory assist, and circulatory assist. Proof of regeneration of these healthy tissues and/or organs is demonstrated in the short-term recovery of end-stage organ failure patients (artificial organs for bridge to regeneration). A third group of artificial organs for the bridge to regeneration accelerates the regenerating process of the patient's healthy tissues and organs. This group includes neurostimulators, artificial blood (red cells) blood oxygenators, and plasmapheresis devices, including hemodiafiltrators. So-called "therapeutic artificial organs" fall into this category (artificial organs to accelerate regeneration). Thus, almost all of today's artificial organs are useful in the bridge to regeneration of healthy natural tissues and organs

Quo Vadis medycyno regeneracyjna?: Quo Vadis Regenerative Medicine?

Science.gov (United States)

Ratajczak, Mariusz Z; Suszyńska, Malwina

2013-07-01

There are presented the most important sources of pluripotent stem cells for potential application in the regenerative medicine. This review summarizes also advantages and disadvantages for potential application of these cells in clinical medicine.

Innovative regenerative medicines in the EU: a better future in evidence?

Science.gov (United States)

Corbett, Mark S; Webster, Andrew; Hawkins, Robert; Woolacott, Nerys

2017-03-08

Despite a steady stream of headlines suggesting they will transform the future of healthcare, high-tech regenerative medicines have, to date, been quite inaccessible to patients, with only eight having been granted an EU marketing licence in the last 7 years. Here, we outline some of the historical reasons for this paucity of licensed innovative regenerative medicines. We discuss the challenges to be overcome to expedite the development of this complex and rapidly changing area of medicine, together with possible reasons to be more optimistic for the future. Several factors have contributed to the scarcity of cutting-edge regenerative medicines in clinical practice. These include the great expense and difficulties involved in planning how individual therapies will be developed, manufactured to commercial levels and ultimately successfully delivered to patients. Specific challenges also exist when evaluating the safety, efficacy and cost-effectiveness of these therapies. Furthermore, many treatments are used without a licence from the European Medicines Agency, under "Hospital Exemption" from the EC legislation. For products which are licensed, alternative financing approaches by healthcare providers may be needed, since many therapies will have significant up-front costs but uncertain benefits and harms in the long-term. However, increasing political interest and more flexible mechanisms for licensing and financing of therapies are now evident; these could be key to the future growth and development of regenerative medicine in clinical practice. Recent developments in regulatory processes, coupled with increasing political interest, may offer some hope for improvements to the long and often difficult routes from laboratory to marketplace for leading-edge cell or tissue therapies. Collaboration between publicly-funded researchers and the pharmaceutical industry could be key to the future development of regenerative medicine in clinical practice; such collaborations

[Ethical aspects of regenerative medicine, with special reference to embryonic stem cells and therapeutic cloning].

Science.gov (United States)

Imura, Hiroo

2003-03-01

Regenerative medicine is expected to be new therapeutic means for treating incurable diseases but requires serious bioethical consideration. Embryonic stem(ES) cells, that are pleuripotent cells suitable to regenerative medicine, can be used in Japan for investigative use under a strict control by guide-lines. On the other hand, use of embryo produced by nuclear transfer has not been allowed in Japan and further serious consideration is required. Some other ethical aspects of regenerative medicine are also discussed.

REGENERATIVE DESIGN PRACTICES IN NIGERIA: A CASE ...

African Journals Online (AJOL)

User

2017-07-01

Jul 1, 2017 ... a view to effectively implement the concept within the study area. ... REGENERATIVE DESIGN PRACTICES IN NIGERIA: A CASE STUDY OF NGOZIKA HOUSING .... could mean greater acceptance of new development by the public and .... human/environment relations based on the Cartesian separation of ...

Ultrastructural study of the chromatoid body in planarian regenerative cells

Energy Technology Data Exchange (ETDEWEB)

Hori, I. (Kanazawa Medical Univ., Ishikawa (Japan))

1982-04-01

The present paper deals with the ultrastructural changes of chromatoid bodies in planarian regenerative cells under normal and experimental conditions. A close relationship was usually observed between chromatoid bodies and pore regions of the nuclear envelope in these cells. The chromatoid bodies continued to decrease in size during cytodifferentiation of regenerative cells, though they did not disappear entirely throughout the regeneration processes. Cytochemistry and (/sup 3/H)uridine autoradiography have shown that the chromatoid body contains RNA. The typical morphological effect of actinomycin D became apparent in three organelles, i.e., nucleolus, polysome and chromatoid body. Ultrastructural changes in nucleoli were observed to occur after actinomycin treatment (20 ..mu..g/ml). The exposure to a higher dose of actinomycin (50 ..mu..g/ml) caused a decay of chromatoid bodies while nuclear envelopes retained numerous pores. Both the nucleoli and the chromatoid bodies disappeared in the sequential stages. Within the cytoplasm of such cells disintegration of a polysomal pattern was correlated with the disappearance of chromatoid bodies. The significance of the planarian chromatoid body is discussed in relation to differentiation of the regenerative cells.

Error-rate performance analysis of opportunistic regenerative relaying

KAUST Repository

Tourki, Kamel; Yang, Hongchuan; Alouini, Mohamed-Slim

2011-01-01

In this paper, we investigate an opportunistic relaying scheme where the selected relay assists the source-destination (direct) communication. In our study, we consider a regenerative opportunistic relaying scheme in which the direct path can

The Ohrberg solar village; Solarsiedlung am Ohrberg

Energy Technology Data Exchange (ETDEWEB)

Vanoli, K.; Christoffers, D.; Rockendorf, G. [Institut fuer Solarenergieforschung GmbH Hameln/Emmerthal (ISFH), Emmerthal (Germany). Abt. Systemtechnik von Solarenergieanlagen; Kranz, R. [Elektrizitaetswerke Wesertal GmbH, Hameln (Germany). Abt. Energieberatung/Energiekonzepte

1998-02-01

As an officially approved regional project of the EXPO 2000, the Ohrberg Solar Village will demonstrate an integrated energy concept - combining customer information and counseling, modern energy technologies and energy services rendered by utilities - which reduces the consumption of conventional energy ressources and the CO{sub 2}-emissions. The local utility Wesertal GmbH will equip the 82 low-energy solar houses of the village with reliable, cost-effective and innovative energy technologies and will provide energy services on the basis of a user-friendly contract. (orig.) [Deutsch] Die Solarsiedlung am Ohrberg demonstriert als registriertes Regionalprojekt der EXPO 2000, wie ein integriertes Energiekonzept - bestehend aus umfassender Energieberatung, Einsatz moderner Energietechnologien und einem Nutz-Energie-Dienstleistungsangebot der Energieversorger - einen substantiellen Beitrag zur Ressourcenschonung und zur Reduzierung der klimarelevanten Umweltbelastung leisten kann. Das regionale Energieversorgungsunternehmen Wesertal GmbH wird innovative, erprobte, kostenguenstige, rationelle und regenerative Energieversorgungstechniken in den 82 solaren Niedrigenergiehaeusern dieser Siedlung installieren und die Waermeversorgung im Rahmen eines Waermedienstleistungskonzeptes uebernehmen. (orig.)

Long-term transition to power/hydrogen energy system based on regenerative energy sources. Langfristiger Uebergang zum Strom/Wasserstoff-Energiesystem auf der Basis erneuerbarer Energiequellen

Energy Technology Data Exchange (ETDEWEB)

Wurster, R

1989-01-01

If we mean to secure the future of this planet in its present state we shall have to reduce drastically the emissions of trace gases influencing our climate like CO/sub 2/, CH/sub 4/, FCHC, ozone, N/sub 2/O and stratospheric H/sub 2/O. CO/sub -/neutral energy sources in clude nuclear energy and regenerative energies (solar, wind, water, biomass, tidal energy). These energy sources provide energy carriers in terms of electricity, heat, biofuels, synthesis gas and hydrogen. The author discusses the power/hydrogen energy system, electrolytic generation of hydrogen and its capacity for storage and transport from sunny solar-energy utilization areas (Central Africa). Hydrogen can then be used in drive systems, power generation (power stations) and for space heating and process heat. The author discusses its profitability and underlines the fact that hydrogen will figure in the energy economy of the future. (HWJ).

Regenerative Payload for GSAT-3 & Advanced Communication ...

Indian Academy of Sciences (India)

First page Back Continue Last page Overview Graphics. Regenerative Payload for GSAT-3 & Advanced Communication Series Satellite. GSAT-4. 8 Ka -Band Spot Beams; 8 Narrow Band (64Kbps) Channels/ Beam; 1 Wide Band (2Mbps) Channel/ Beam;; 64 Kbps Signaling Channel; On-Board Switch Matrix; 8 Channel ...

Regenerative adsorbent heat pump

Science.gov (United States)

Jones, Jack A. (Inventor)

1991-01-01

A regenerative adsorbent heat pump process and system is provided which can regenerate a high percentage of the sensible heat of the system and at least a portion of the heat of adsorption. A series of at least four compressors containing an adsorbent is provided. A large amount of heat is transferred from compressor to compressor so that heat is regenerated. The process and system are useful for air conditioning rooms, providing room heat in the winter or for hot water heating throughout the year, and, in general, for pumping heat from a lower temperature to a higher temperature.

Highly Efficient, Durable Regenerative Solid Oxide Stack, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Precision Combustion, Inc. (PCI) proposes to develop a highly efficient regenerative solid oxide stack design. Novel structural elements allow direct internal...

Two sides of the same coin: stem cells in cancer and regenerative medicine.

Science.gov (United States)

Ilmer, Matthias; Vykoukal, Jody; Recio Boiles, Alejandro; Coleman, Michael; Alt, Eckhard

2014-07-01

Multipotent stromal cells (MSCs) derived from bone marrow, adipose tissue, cord blood, and other origins have recently received much attention as potential therapeutic agents with beneficial immunomodulatory and regenerative properties. In their native tissue environment, however, such cells also appear to have essential functions in building and supporting tumor microenvironments, providing metastatic niches, and maintaining cancer hallmarks. Here, we consider the varied roles of these tissue-resident stroma-associated cells, synthesize recent and emerging discoveries, and discuss the role, potential, and clinical applications of MSCs in cancer and regenerative medicine.-Ilmer, M., Vykoukal, J., Recio Boiles, A., Coleman, M., Alt, E. Two sides of the same coin: stem cells in cancer and regenerative medicine. © FASEB.

Mechanism analysis and evaluation methodology of regenerative braking contribution to energy efficiency improvement of electrified vehicles

International Nuclear Information System (INIS)

Lv, Chen; Zhang, Junzhi; Li, Yutong; Yuan, Ye

2015-01-01

Highlights: • The energy flow of an electric vehicle with regenerative brake is analyzed. • Methodology for measuring the regen brake contribution is discussed. • Evaluation parameters of regen brake contribution are proposed. • Vehicle tests are carried out on chassis dynamometer. • Test results verify the evaluation method and parameters proposed. - Abstract: This article discusses the mechanism and evaluation methods of contribution brought by regenerative braking to electric vehicle’s energy efficiency improvement. The energy flow of an electric vehicle considering the braking energy regeneration was analyzed. Then, methodologies for measuring the contribution made by regenerative brake to vehicle energy efficiency improvement were introduced. Based on the energy flow analyzed, two different evaluation parameters were proposed. Vehicle tests were carried out on chassis dynamometer under typical driving cycles with three different control strategies. The experimental results the difference between the proposed two evaluation parameters, and demonstrated the feasibility and effectiveness of the evaluation methodologies proposed

Active Magnetic Regenerative Liquefier

Energy Technology Data Exchange (ETDEWEB)

Barclay, John A. [Heracles Energy Corporation d.b.a. Prometheus Energy, Washington, DC (United States); Oseen-Send, Kathryn [Heracles Energy Corporation d.b.a. Prometheus Energy, Washington, DC (United States); Ferguson, Luke [Heracles Energy Corporation d.b.a. Prometheus Energy, Washington, DC (United States); Pouresfandiary, Jamshid [Heracles Energy Corporation d.b.a. Prometheus Energy, Washington, DC (United States); Cousins, Anand [Heracles Energy Corporation d.b.a. Prometheus Energy, Washington, DC (United States); Ralph, Heather [Heracles Energy Corporation d.b.a. Prometheus Energy, Washington, DC (United States); Hampto, Tom [Heracles Energy Corporation d.b.a. Prometheus Energy, Washington, DC (United States)

2016-01-12

This final report for the DOE Project entitled Active Magnetic Regenerative Liquefier (AMRL) funded under Grant DE-FG36-08GO18064 to Heracles Energy Corporation d.b.a. Prometheus Energy (Heracles/Prometheus) describes an active magnetic regenerative refrigerator (AMRR) prototype designed and built during the period from July 2008 through May 2011. The primary goal of this project was to make significant technical advances toward highly efficient liquefaction of hydrogen. Conventional hydrogen liquefiers at any scale have a maximum FOM of ~0.35 due primarily to the intrinsic difficulty of rapid, efficient compression of either hydrogen or helium working gases. Numerical simulation modeling of high performance AMRL designs indicates certain designs have promise to increase thermodynamic efficiency from a FOM of ~0.35 toward ~0.5 to ~0.6. The technical approach was the use of solid magnetic working refrigerants cycled in and out of high magnetic fields to build an efficient active regenerative magnetic refrigeration module providing cooling power for AMRL. A single-stage reciprocating AMRR with a design temperature span from ~290 K to ~120 K was built and tested with dual magnetic regenerators moving in and out of the conductively-cooled superconducting magnet subsystem. The heat transfer fluid (helium) was coupled to the process stream (refrigeration/liquefaction load) via high performance heat exchangers. In order to maximize AMRR efficiency a helium bypass loop with adjustable flow was incorporated in the design because the thermal mass of magnetic refrigerants is higher in low magnetic field than in high magnetic field. Heracles/Prometheus designed experiments to measure AMRR performance under a variety of different operational parameters such as cycle frequency, magnetic field strength, heat transfer fluid flow rate, amount of bypass flow of the heat transfer fluid while measuring work input, temperature span, cooling capability as a function of cold temperature

Design, clinical translation and immunological response of biomaterials in regenerative medicine

Science.gov (United States)

Sadtler, Kaitlyn; Singh, Anirudha; Wolf, Matthew T.; Wang, Xiaokun; Pardoll, Drew M.; Elisseeff, Jennifer H.

2016-07-01

The field of regenerative medicine aims to replace tissues lost as a consequence of disease, trauma or congenital abnormalities. Biomaterials serve as scaffolds for regenerative medicine to deliver cells, provide biological signals and physical support, and mobilize endogenous cells to repair tissues. Sophisticated chemistries are used to synthesize materials that mimic and modulate native tissue microenvironments, to replace form and to elucidate structure-function relationships of cell-material interactions. The therapeutic relevance of these biomaterial properties can only be studied after clinical translation, whereby key parameters for efficacy can be defined and then used for future design. In this Review, we present the development and translation of biomaterials for two tissue engineering targets, cartilage and cornea, both of which lack the ability to self-repair. Finally, looking to the future, we discuss the role of the immune system in regeneration and the potential for biomaterial scaffolds to modulate immune signalling to create a pro-regenerative environment.

Development of a computer code for a regenerative Rankine cycle analysis

International Nuclear Information System (INIS)

Wi, Myung Hwan; Kim, Seong O; Choi, Seok Ki; Kim, Jin Hwan

2005-01-01

A regenerative Rankine cycle can increase the thermal efficiency of a steam system without increasing the steam pressure and temperature. The regenerative process involves heating the feedwater on its return trip to the steam generator by extracting steam at various stages of the turbine and transferring the energy to the feedwater via a feedwater heater. Some real plants use more than five feedwater heaters to enhance the cycle efficiency. However, the optimum number of feedwater heaters required is determined by balancing the efficiency improvement against the capital investment for a given cycle. In the present study, the computer code, TAOPCS, for the thermodynamic analysis of a regenerative steam cycle was developed to optimally design and accurately analyze the behavior of the power conversion system of Korea Advance Liquid Metal Reactor (KALIMER). In order to understand the functions and the characteristics of the code, the main features of the TAPCS were described and the example results are presented in this paper

Liver regenerative medicine: advances and challenges.

Science.gov (United States)

Chistiakov, Dimitry A

2012-01-01

Liver transplantation is the standard care for many end-stage liver diseases. However, donor organs are scarce and some people succumb to liver failure before a donor is found. Liver regenerative medicine is a special interdisciplinary field of medicine focused on the development of new therapies incorporating stem cells, gene therapy and engineered tissues in order to repair or replace the damaged organ. In this review we consider the emerging progress achieved in the hepatic regenerative medicine within the last decade. The review starts with the characterization of liver organogenesis, fetal and adult stem/progenitor cells. Then, applications of primary hepatocytes, embryonic and adult (mesenchymal, hematopoietic and induced pluripotent) stem cells in cell therapy of liver diseases are considered. Current advances and challenges in producing mature hepatocytes from stem/progenitor cells are discussed. A section about hepatic tissue engineering includes consideration of synthetic and natural biomaterials in engineering scaffolds, strategies and achievements in the development of 3D bioactive matrices and 3D hepatocyte cultures, liver microengineering, generating bioartificial liver and prospects for fabrication of the bioengineered liver. Copyright © 2012 S. Karger AG, Basel.

Scaffolds in regenerative endodontics: A review

Science.gov (United States)

Gathani, Kinjal M.; Raghavendra, Srinidhi Surya

2016-01-01

Root canal therapy has enabled us to save numerous teeth over the years. The most desired outcome of endodontic treatment would be when diseased or nonvital pulp is replaced with healthy pulp tissue that would revitalize the teeth through regenerative endodontics. ‘A search was conducted using the Pubmed and MEDLINE databases for articles with the criteria ‘Platelet rich plasma’, ‘Platelet rich fibrin’, ‘Stem cells’, ‘Natural and artificial scaffolds’ from 1982–2015’. Tissues are organized as three-dimensional structures, and appropriate scaffolding is necessary to provide a spatially correct position of cell location and regulate differentiation, proliferation, or metabolism of the stem cells. Extracellular matrix molecules control the differentiation of stem cells, and an appropriate scaffold might selectively bind and localize cells, contain growth factors, and undergo biodegradation over time. Different scaffolds facilitate the regeneration of different tissues. To ensure a successful regenerative procedure, it is essential to have a thorough and precise knowledge about the suitable scaffold for the required tissue. This article gives a review on the different scaffolds providing an insight into the new developmental approaches on the horizon. PMID:27857762

Scaffolds in regenerative endodontics: A review

Directory of Open Access Journals (Sweden)

Kinjal M Gathani

2016-01-01

Full Text Available Root canal therapy has enabled us to save numerous teeth over the years. The most desired outcome of endodontic treatment would be when diseased or nonvital pulp is replaced with healthy pulp tissue that would revitalize the teeth through regenerative endodontics. ′A search was conducted using the Pubmed and MEDLINE databases for articles with the criteria ′Platelet rich plasma′, ′Platelet rich fibrin′, ′Stem cells′, ′Natural and artificial scaffolds′ from 1982-2015′. Tissues are organized as three-dimensional structures, and appropriate scaffolding is necessary to provide a spatially correct position of cell location and regulate differentiation, proliferation, or metabolism of the stem cells. Extracellular matrix molecules control the differentiation of stem cells, and an appropriate scaffold might selectively bind and localize cells, contain growth factors, and undergo biodegradation over time. Different scaffolds facilitate the regeneration of different tissues. To ensure a successful regenerative procedure, it is essential to have a thorough and precise knowledge about the suitable scaffold for the required tissue. This article gives a review on the different scaffolds providing an insight into the new developmental approaches on the horizon.

AeroVironment technician checks a Helios solar cell panel

Science.gov (United States)

2000-01-01

A technician at AeroVironment's Design Development Center in Simi Valley, California, checks a panel of silicon solar cells for conductivity and voltage. The bi-facial cells, fabricated by SunPower, Inc., of Sunnyvale, California, are among 64,000 solar cells which have been installed on the Helios Prototype solar-powered aircraft to provide power to its 14 electric motors and operating systems. Developed by AeroVironment under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) project, the Helios Prototype is the forerunner of a planned fleet of slow-flying, long duration, high-altitude aircraft which can perform atmospheric science missions and serve as telecommunications relay platforms in the stratosphere. Target goals set by NASA for the giant 246-foot span flying wing include reaching and sustaining subsonic horizontal flight at 100,000 feet altitude in 2001, and sustained continuous flight for at least four days and nights above 50,000 feet altitude with the aid of a regenerative fuel cell-based energy storage system now under development in 2003.

Use of elastomers in regenerative braking systems

Science.gov (United States)

The storage of potential energy as strain energy in elastomers was investigated. The evolution of the preferred stressing scheme is described, and test results on full-size elastomeric energy storage units sized for an automotive regenerative braking system application are presented. The need for elastomeric material improvements is also discussed.

Stem cells and regenerative medicine in domestic and companion animals: a multispecies perspective.

Science.gov (United States)

Gonçalves, N N; Ambrósio, C E; Piedrahita, J A

2014-10-01

Since their original isolation, the majority of the work on embryonic stem cells (ESC) has been carried out in mice. While the mouse is an outstanding model for basic research, it also has considerable limitations for translational work, especially in the area of regenerative medicine. This is due to a combination of factors that include physiological and size differences when compared to humans. In contrast, domestic animal species, such as swine, and companion animal species, such as dogs, provide unique opportunities to develop regenerative medicine protocols that can then be utilized in humans. Unfortunately, at present, the state of knowledge related to, and availability of, ESC from domestic animals vary among species such as pig, horse, dog and cat, and without exception lags significantly behind the mouse and human. It is clear that much still needs to be discovered. The 'stem cell-like' cell lines being reported are still not satisfactorily used in regenerative medicine, due to reasons such as heterogeneity and chromosomal instability. As a result, investigators have searched for alternate source of cells that can be used for regenerative medicine. This approach has uncovered a range of adult stem cells and adult progenitor cells that have utility in both human and veterinary medicine. Here, we review a range of stem cells, from ESC to induced pluripotent stem cells, and discuss their potential application in the field of regenerative medicine. © 2014 Blackwell Verlag GmbH.

New model of inverting substation for DC traction with regenerative braking system

Science.gov (United States)

Omar, Abdul Malek Saidina; Samat, Ahmad Asri Abd; Isa, Siti Sarah Mat; Shamsuddin, Sarah Addyani; Jamaludin, Nur Fadhilah; Khyasudeen, Muhammad Farris

2017-08-01

This paper presents a power electronic devices application focus on modeling, analysis, and control of switching power converter in the inverting DC substation with regenerative braking system which is used to recycle the surplus regenerative power by feed it back to the main AC grid. The main objective of this research is to improve the switching power electronic converter of the railway inverting substation and optimize the maximum kinetic energy recovery together with minimum power losses from the railway braking system. Assess performance including efficiency and robustness will be evaluated in order to get the best solution for the design configuration. Research methodology included mathematical calculation, simulation, and detail analysis on modeling of switching power converter on inverting substation. The design stage separates to four main areas include rectification mode, regenerative mode, control inverter mode and filtering mode. The simulation result has shown that the regenerative inverter has a capability to accept a maximum recovery power on the regeneration mode. Total energy recovery has increase and power losses have decreases because inverter abilities to transfer the surplus energy back to the main AC supply. An Inverter controller with PWM Generator and PI Voltage Regulator has been designed to control voltage magnitude and frequency of the DC traction system.

For the definition of capacity effects of electricity generation from wind power and solar radiation

International Nuclear Information System (INIS)

Kaltschmitt, M.

1996-01-01

It is the objective of this contribution to define the calculable really available output of a fluctuating electricity generation from wind energy and solar radiation. Apart from that, the methods for determining the really available output are explained, as far as they are necessary for understanding the definitions. Exemplified on a simulated large-scale regenerative electricity generation in Germany, in addition, some defined values are calculated and discussed. (orig.) [de

Parameters Design for a Parallel Hybrid Electric Bus Using Regenerative Brake Model

Directory of Open Access Journals (Sweden)

Zilin Ma

2014-01-01

Full Text Available A design methodology which uses the regenerative brake model is introduced to determine the major system parameters of a parallel electric hybrid bus drive train. Hybrid system parameters mainly include the power rating of internal combustion engine (ICE, gear ratios of transmission, power rating, and maximal torque of motor, power, and capacity of battery. The regenerative model is built in the vehicle model to estimate the regenerative energy in the real road conditions. The design target is to ensure that the vehicle meets the specified vehicle performance, such as speed and acceleration, and at the same time, operates the ICE within an expected speed range. Several pairs of parameters are selected from the result analysis, and the fuel saving result in the road test shows that a 25% reduction is achieved in fuel consumption.

Regenerative dentistry: translating advancements in basic science research to the dental practice.

Science.gov (United States)

Garcia-Godoy, Franklin; Murray, Peter

2010-01-01

Scientific advances in the creation of restorative biomaterials, in vitro cell culture technology, tissue engineering, molecular biology and the human genome project provide the basis for the introduction of new technologies into dentistry. This review provides an assessment of how tissue engineering, stem cell, genetic transfer, biomaterial and growth factor therapies can be integrated into clinical dental therapies to restore and regenerate oral tissues. In parallel to the creation of a new field in general medicine called "regenerative medicine," we call this field "regenerative dentistry." While the problems of introducing regenerative therapies are substantial, the potential benefits to patients and the profession are equally ground-breaking. In this review, we outline a few areas of interest for the future of oral and dental medicine in which advancements in basic science have already been adapted to fit the goals of 21st century dentistry.

Hypoxia-based strategies for regenerative dentistry-Views from the different dental fields.

Science.gov (United States)

Müller, Anna Sonja; Janjić, Klara; Lilaj, Bledar; Edelmayer, Michael; Agis, Hermann

2017-09-01

The understanding of the cell biological processes underlying development and regeneration of oral tissues leads to novel regenerative approaches. Over the past years, knowledge on key roles of the hypoxia-based response has become more profound. Based on these findings, novel regenerative approaches for dentistry are emerging, which target cellular oxygen sensors. These approaches include hypoxia pre-conditioning and pharmacologically simulated hypoxia. The increase in studies on hypoxia and hypoxia-based strategies in regenerative dentistry highlights the growing attention to hypoxia's role in regeneration and its underlying biology, as well as its application in a therapeutic setting. In this narrative review, we present the current knowledge on the role of hypoxia in oral tissues and review the proposed hypoxia-based approaches in different fields of dentistry, including endodontics, orthodontics, periodontics, and oral surgery. Copyright © 2017 Elsevier Ltd. All rights reserved.

Development of Regenerative Braking Co-operative Control System for Automatic Transmission-based Hybrid Electric Vehicle using Electronic Wedge Brake

OpenAIRE

Ko, Jiweon; Ko, Sungyeon; Bak, Yongsun; Jang, Mijeong; Yoo, Byoungsoo; Cheon, Jaeseung; Kim, Hyunsoo

2013-01-01

This research proposes a regenerative braking co-operative control system for the automatic transmission (AT)-based hybrid electric vehicle (HEV). The brake system of the subject HEV consists of the regenerative braking and the electronic wedge brake (EWB) friction braking for the front wheel, and the hydraulic friction braking for the rear wheel. A regenerative braking co-operative control algorithm is suggested for the regenerative braking and friction braking, which distributes the braking...

The current 'state of play' of regenerative medicine in horses: what the horse can tell the human.

Science.gov (United States)

Smith, Roger Kw; Garvican, Elaine R; Fortier, Lisa A

2014-01-01

The horse is an attractive model for many human age-related degenerative diseases of the musculoskeletal system because it is a large animal species that both ages and exercises, and develops naturally occurring injuries with many similarities to the human counterpart. It therefore represents an ideal species to use as a 'proving ground' for new therapies, most notably regenerative medicine. Regenerative techniques using cell-based therapies for the treatment of equine musculoskeletal disease have been in use for over a decade. This review article provides a summary overview of the sources, current challenges and problems surrounding the use of stem cell and non-cell-based therapy in regenerative medicine in horses and is based on presentations from a recent Havemeyer symposium on equine regenerative medicine where speakers are selected from leading authorities in both equine and human regenerative medicine fields from 10 different countries.

Advanced Space Power Systems (ASPS): Regenerative Fuel Cells (RFC)

Data.gov (United States)

National Aeronautics and Space Administration — The objective of the regenerative fuel cell project element is to develop power and energy storage technologies that enable new capabilities for future human space...

A Study on Control Strategy of Regenerative Braking in the Hydraulic Hybrid Vehicle Based on ECE Regulations

Directory of Open Access Journals (Sweden)

Tao Liu

2013-01-01

Full Text Available This paper establishes a mathematic model of composite braking in the hydraulic hybrid vehicle and analyzes the constraint condition of parallel regenerative braking control algorithm. Based on regenerative braking system character and ECE (Economic Commission of Europe regulations, it introduces the control strategy of regenerative braking in parallel hydraulic hybrid vehicle (PHHV. Finally, the paper establishes the backward simulation model of the hydraulic hybrid vehicle in Matlab/simulink and makes a simulation analysis of the control strategy of regenerative braking. The results show that this strategy can equip the hydraulic hybrid vehicle with strong brake energy recovery power in typical urban drive state.

Free radical scavenging injectable hydrogels for regenerative therapy

Energy Technology Data Exchange (ETDEWEB)

Komeri, Remya [Sree Chitra Tirunal Institute for Medical Sciences and Technology, Polymer Science Division, BMT Wing, Thiruvananthapuram 695 012, Kerala State (India); Thankam, Finosh Gnanaprakasam [Dept. of Biomedical Sciences, Creighton University, 2500 California Plaza, Omaha NE68178 (United States); Muthu, Jayabalan, E-mail: mjayabalan52@gmail.com [Sree Chitra Tirunal Institute for Medical Sciences and Technology, Polymer Science Division, BMT Wing, Thiruvananthapuram 695 012, Kerala State (India)

2017-02-01

Pathological free radicals generated from inflamed and infarcted cardiac tissues interferes natural tissue repair mechanisms. Hypoxic microenvironment at the injured zone of non-regenerating cardiac tissues hinders the therapeutic attempts including cell therapy. Here we report an injectable, cytocompatible, free radical scavenging synthetic hydrogel formulation for regenerative therapy. New hydrogel (PEAX-P) is prepared with D-xylitol-co-fumarate-co-poly ethylene adipate-co-PEG comaromer (PEAX) and PEGDiacrylate. PEAX-P hydrogel swells 4.9 times the initial weight and retains 100.07 kPa Young modulus at equilibrium swelling, which is suitable for cardiac applications. PEAX-P hydrogel retains elastic nature even at 60% compressive strain, which is favorable to fit with the dynamic and elastic natural tissue counterparts. PEAX-P hydrogel scavenges 51% DPPH radical, 40% hydroxyl radicals 41% nitrate radicals with 31% reducing power. The presence of hydrogel protects 62% cardiomyoblast cells treated with stress inducing media at LD 50 concentration. The free hydroxyl groups in sugar alcohols of the comacromer influence the free radical scavenging. Comparatively, PEAX-P hydrogel based on xylitol evinces slightly lower scavenging characteristics than with previously reported PEAM-P hydrogel containing mannitol having more hydroxyl groups. The possible free radical scavenging mechanism of the present hydrogel relies on the free π electrons associated with uncrosslinked fumarate bonds, hydrogen atoms associated with sugar alcohols/PEG and radical dilution by free water in the matrix. Briefly, the present PEAX-P hydrogel is a potential injectable system for combined antioxidant and regenerative therapy. - Graphical abstract: Injectable hydrogel with inherent free radical scavenging property for regenerative tissue engineering application. - Highlights: • Novel injectable hydrogel (PEAX-P) is prepared using D-xylitol-co-fumarate-co-poly ethylene adipate-co-PEG comaromer

Free radical scavenging injectable hydrogels for regenerative therapy

International Nuclear Information System (INIS)

Komeri, Remya; Thankam, Finosh Gnanaprakasam; Muthu, Jayabalan

2017-01-01

Pathological free radicals generated from inflamed and infarcted cardiac tissues interferes natural tissue repair mechanisms. Hypoxic microenvironment at the injured zone of non-regenerating cardiac tissues hinders the therapeutic attempts including cell therapy. Here we report an injectable, cytocompatible, free radical scavenging synthetic hydrogel formulation for regenerative therapy. New hydrogel (PEAX-P) is prepared with D-xylitol-co-fumarate-co-poly ethylene adipate-co-PEG comaromer (PEAX) and PEGDiacrylate. PEAX-P hydrogel swells 4.9 times the initial weight and retains 100.07 kPa Young modulus at equilibrium swelling, which is suitable for cardiac applications. PEAX-P hydrogel retains elastic nature even at 60% compressive strain, which is favorable to fit with the dynamic and elastic natural tissue counterparts. PEAX-P hydrogel scavenges 51% DPPH radical, 40% hydroxyl radicals 41% nitrate radicals with 31% reducing power. The presence of hydrogel protects 62% cardiomyoblast cells treated with stress inducing media at LD 50 concentration. The free hydroxyl groups in sugar alcohols of the comacromer influence the free radical scavenging. Comparatively, PEAX-P hydrogel based on xylitol evinces slightly lower scavenging characteristics than with previously reported PEAM-P hydrogel containing mannitol having more hydroxyl groups. The possible free radical scavenging mechanism of the present hydrogel relies on the free π electrons associated with uncrosslinked fumarate bonds, hydrogen atoms associated with sugar alcohols/PEG and radical dilution by free water in the matrix. Briefly, the present PEAX-P hydrogel is a potential injectable system for combined antioxidant and regenerative therapy. - Graphical abstract: Injectable hydrogel with inherent free radical scavenging property for regenerative tissue engineering application. - Highlights: • Novel injectable hydrogel (PEAX-P) is prepared using D-xylitol-co-fumarate-co-poly ethylene adipate-co-PEG comaromer

A regenerative biology view on artificial tissue construction and 3D bioprinting: what may we learn from natural regenerative phenomena?

DEFF Research Database (Denmark)

Lauridsen, Henrik

2017-01-01

The implications of the low tissue regenerative potential in humans are severe and widespread. Several of our major diseases are direct results of this deficiency that leaves us vulnerable to events of tissue damage. This is opposed to some animal groups, such as the urodele amphibians (salamanders...

Educational tool for modeling and simulation of a closed regenerative life support system

Science.gov (United States)

Arai, Tatsuya; Fanchiang, Christine; Aoki, Hirofumi; Newman, Dava J.

For long term missions on the moon and Mars, regenerative life support systems emerge as a promising key technology for sustaining successful explorations with reduced re-supply logistics and cost. The purpose of this study was to create a simple model of a regenerative life support system which allows preliminary investigation of system responses. A simplified regenerative life support system was made with MATLAB Simulink ™. Mass flows in the system were simplified to carbon, water, oxygen and carbon dioxide. The subsystems included crew members, animals, a plant module, and a waste processor, which exchanged mass into and out of mass reservoirs. Preliminary numerical simulations were carried out to observe system responses. The simplified life support system model allowed preliminary investigation of the system response to perturbations such as increased or decreased number of crew members. The model is simple and flexible enough to add new components, and also possible to numerically predict non-linear subsystem functions and responses. Future work includes practical issues such as energy efficiency, air leakage, nutrition, and plant growth modeling. The model functions as an effective teaching tool about how a regenerative advanced life support system works.

Energy recapture through deceleration - regenerative braking in electric vehicles from a user perspective.

Science.gov (United States)

Cocron, Peter; Bühler, Franziska; Franke, Thomas; Neumann, Isabel; Dielmann, Benno; Krems, Josef F

2013-01-01

We report results from a 1-year field study (N = 80) on user interactions with regenerative braking in electric vehicles. Designed to recapture energy in vehicles with electric powertrains, regenerative braking has an important influence on both the task of driving and energy consumption. Results from user assessments and data from onboard data loggers indicate that most drivers quickly learned to interact with the system, which was triggered via accelerator. Further, conventional braking manoeuvres decreased significantly as the majority of deceleration episodes could only be executed through regenerative braking. Still, some drivers reported difficulties when adapting to the system. These difficulties could be addressed by offering different levels of regeneration so that the intensity of the deceleration could be individually modified. In general, the system is trusted and regarded as a valuable tool for prolonging range. Regenerative braking in electric vehicles has direct implications for the driving task. We found that drivers quickly learn to use and accept a system, which is triggered via accelerator. For those reporting difficulties in the interaction, it appears reasonable to integrate options to customise or switch off the system.

Electrolyzer for NASA Lunar Regenerative Fuel Cells, Phase II

Data.gov (United States)

National Aeronautics and Space Administration — Water electrolyzer stacks are a key component of regenerative fuel cells, designed to replace batteries as a means of storing electric energy on the lunar surface....

Regenerative medicine: A ray of light for medical science

Directory of Open Access Journals (Sweden)

Swapna Supekar

2016-01-01

Full Text Available The perimeters of medical science have expanded to include regenerative medicine as a translational science, which has the potential to revolutionize the treatment of incapacitating diseases and chronic disorders.

Regenerative adsorption distillation system

KAUST Repository

Ng, Kim Choon; Thu, Kyaw; Amy, Gary; Chunggaze, Mohammed; Al-Ghasham, Tawfiq

2013-01-01

There is provided a regenerative adsorption distillation system comprising a train of distillation effects in fluid communication with each other. The train of distillation effects comprises at least one intermediate effect between the first and last distillation effects of the train, each effect comprising a vessel and a condensing tube for flow of a fluid therein. The system further comprises a pair of adsorption-desorption beds in vapour communication with the last effect and at least one intermediate effect, wherein the beds contain an adsorbent that adsorbs vapour from the last effect and transmits desorbed vapour into at least one of the intermediate effect.

Regenerative adsorption distillation system

KAUST Repository

Ng, Kim Choon

2013-12-26

There is provided a regenerative adsorption distillation system comprising a train of distillation effects in fluid communication with each other. The train of distillation effects comprises at least one intermediate effect between the first and last distillation effects of the train, each effect comprising a vessel and a condensing tube for flow of a fluid therein. The system further comprises a pair of adsorption-desorption beds in vapour communication with the last effect and at least one intermediate effect, wherein the beds contain an adsorbent that adsorbs vapour from the last effect and transmits desorbed vapour into at least one of the intermediate effect.

REAC regenerative treatment efficacy in experimental chondral lesions: a pilot study on ovine animal model

Directory of Open Access Journals (Sweden)

Sanna Passino E

2017-09-01

Full Text Available Eraldo Sanna Passino,1,2 Stefano Rocca,1 Sabrina Caggiu,1 Nicolò Columbano,1,2 Alessandro Castagna,3 Vania Fontani,3–5 Salvatore Rinaldi3–51Department of Veterinary Medicine, University of Sassari, Sassari, Italy; 2Comparative Surgery Research Laboratory, University of Sassari, Sassari, Italy; 3Department of Regenerative Medicine, Rinaldi Fontani Institute, Florence, Italy; 4Research Department, Rinaldi Fontani Foundation, Florence, Italy; 5Research Department, IRF Shanghai Biomedical Sciences, Shanghai, People’s Republic of China Abstract: Radioelectric asymmetric conveyor (REAC technology is a platform designed to optimize cell polarity. Cell polarity is a universal biological phenomenon that is implicated in cell differentiation, proliferation, morphogenesis, aging, and rejuvenation. In this work, we investigate a timing and administration protocol for tissue optimization regenerative treatment type C, in order to treat aging-related chondral damage or injuries and gain insights into regenerative processes of articular cartilage in humans. The chondral lesion produced in this study in an animal model (6 knee joints of 4 adult sheep was 6 mm in diameter and about 2 mm deep. These lesions, which did not involve subchondral bone, tend to increase in size and depth and are not completely repaired with normal hyaline articular cartilage since adult articular cartilage is avascular and has a very slow turnover at the cellular and molecular level. Moreover, the hydration of articular cartilage is reduced with aging and with decreased mitotic activity, synthesis, and population size of chondrocytes. Six months posttreatment, lesions appeared filled, though not completely, with newly generated tissue of the light opalescent color of healthy articular cartilage, which otherwise covered the underlying subchondral bone. The newly formed tissue surface appeared to be quite regular. Nearly complete regeneration of subchondral bone occurred, with

Engineering growth factors for regenerative medicine applications.

Energy Technology Data Exchange (ETDEWEB)

Mitchell, Aaron C.; Briquez, Priscilla S.; Hubbell, Jeffrey A.; Cochran, Jennifer R.

2016-01-15

Growth factors are important morphogenetic proteins that instruct cell behavior and guide tissue repair and renewal. Although their therapeutic potential holds great promise in regenerative medicine applications, translation of growth factors into clinical treatments has been hindered by limitations including poor protein stability, low recombinant expression yield, and suboptimal efficacy. This review highlights current tools, technologies, and approaches to design integrated and effective growth factor-based therapies for regenerative medicine applications. The first section describes rational and combinatorial protein engineering approaches that have been utilized to improve growth factor stability, expression yield, biodistribution, and serum half-life, or alter their cell trafficking behavior or receptor binding affinity. The second section highlights elegant biomaterial-based systems, inspired by the natural extracellular matrix milieu, that have been developed for effective spatial and temporal delivery of growth factors to cell surface receptors. Although appearing distinct, these two approaches are highly complementary and involve principles of molecular design and engineering to be considered in parallel when developing optimal materials for clinical applications.

PRMT7 Preserves Satellite Cell Regenerative Capacity

Directory of Open Access Journals (Sweden)

Roméo Sébastien Blanc

2016-02-01

Full Text Available Regeneration of skeletal muscle requires the continued presence of quiescent muscle stem cells (satellite cells, which become activated in response to injury. Here, we report that whole-body protein arginine methyltransferase PRMT7−/− adult mice and mice conditionally lacking PRMT7 in satellite cells using Pax7-CreERT2 both display a significant reduction in satellite cell function, leading to defects in regenerative capacity upon muscle injury. We show that PRMT7 is preferentially expressed in activated satellite cells and, interestingly, PRMT7-deficient satellite cells undergo cell-cycle arrest and premature cellular senescence. These defects underlie poor satellite cell stem cell capacity to regenerate muscle and self-renew after injury. PRMT7-deficient satellite cells express elevated levels of the CDK inhibitor p21CIP1 and low levels of its repressor, DNMT3b. Restoration of DNMT3b in PRMT7-deficient cells rescues PRMT7-mediated senescence. Our findings define PRMT7 as a regulator of the DNMT3b/p21 axis required to maintain muscle stem cell regenerative capacity.

Multiple excitation regenerative amplifier inertial confinement system

International Nuclear Information System (INIS)

George, V.E.; Haas, R.A.; Krupke, W.F.; Schlitt, L.G.

1980-01-01

The invention relates to apparatus and methods for producing high intensity laser radiation generation which is achieved through an optical amplifier-storage ring design. One or two synchronized, counterpropagating laser pulses are injected into a regenerative amplifier cavity and amplified by gain media which are pumped repetitively by electrical or optical means. The gain media excitation pulses are tailored to efficiently amplify the laser pulses during each transit. After the laser pulses have been amplified to the desired intensity level, they are either switched out of the cavity by some switch means, as for example an electro-optical device, for any well known laser end uses, or a target means may be injected into the regenerative amplifier cavity in such a way as to intercept simultaneously the counterpropagating laser pulses. One such well known end uses to which this invention is intended is for production of high density and temperature plasmas suitable for generating neutrons, ions and x-rays and for studying matter heated by high intensity laser radiation

Enhanced Regenerative Braking Strategies for Electric Vehicles: Dynamic Performance and Potential Analysis

OpenAIRE

Boyi Xiao; Huazhong Lu; Hailin Wang; Jiageng Ruan; Nong Zhang

2017-01-01

A regenerative braking system and hydraulic braking system are used in conjunction in the majority of electric vehicles worldwide. We propose a new regenerative braking distribution strategy that is based on multi-input fuzzy control logic while considering the influences of the battery’s state of charge, the brake strength and the motor speed. To verify the braking performance and recovery economy, this strategy was applied to a battery electric vehicle model and compared with two other impr...

MSCs-derived exosomes: cell-secreted nanovesicles with regenerative potential

Directory of Open Access Journals (Sweden)

Ana Marote

2016-08-01

Full Text Available Exosomes are membrane-enclosed nanovesicles (30-150 nm that shuttle active cargoes between different cells. These tiny extracellular vesicles have been recently isolated from mesenchymal stem cells (MSCs conditioned medium, a population of multipotent cells identified in several adult tissues. MSCs paracrine activity has been already shown to be the key mediator of their elicited regenerative effects. On the other hand, the individual contribution of MSCs-derived exosomes for these effects is only now being unraveled. The administration of MSCs-derived exosomes has been demonstrated to restore tissue function in multiple diseases/injury models and to induce beneficial in vitro effects, mainly mediated by exosomal-enclosed miRNAs. Additionally, the source and the culture conditions of MSCs have been shown to influence the regenerative responses induced by exosomes. Therefore, these studies reveal that MSCs-derived exosomes hold a great potential for cell-free therapies that are safer and easier to manipulate than cell-based products. Nevertheless, this is an emerging research field and hence, further studies are required to understand the full dimension of this complex intercellular communication system and how it can be optimized to take full advantage of its therapeutic effects. In this mini-review, we summarize the most significant new advances in the regenerative properties of MSCs-derived exosomes and discuss the molecular mechanisms underlying these effects.

A Study on Control Strategy of Regenerative Braking in the Hydraulic Hybrid Vehicle Based on ECE Regulations

OpenAIRE

Liu, Tao; Zheng, Jincheng; Su, Yongmao; Zhao, Jinghui

2013-01-01

This paper establishes a mathematic model of composite braking in the hydraulic hybrid vehicle and analyzes the constraint condition of parallel regenerative braking control algorithm. Based on regenerative braking system character and ECE (Economic Commission of Europe) regulations, it introduces the control strategy of regenerative braking in parallel hydraulic hybrid vehicle (PHHV). Finally, the paper establishes the backward simulation model of the hydraulic hybrid vehicle in Matlab/simul...

An ultrastructural study of the chromatoid body in planarian regenerative cells

International Nuclear Information System (INIS)

Hori, Isao

1982-01-01

The present paper deals with the ultrastructural changes of chromatoid bodies in planarian regenerative cells under normal and experimental conditions. A close relationship was usually observed between chromatoid bodies and pore regions of the nuclear envelope in these cells. The chromatoid bodies continued to decrease in size during cytodifferentiation of regenerative cells, though they did not disappear entirely throughout the regeneration processes. Cytochemistry and [ 3 H]uridine autoradiography have shown that the chromatoid body contains RNA. The typical morphological effect of actinomycin D became apparent in three organelles, i.e., nucleolus, polysome and chromatoid body. Ultrastructural changes in nucleoli were observed to occur after actinomycin treatment (20 μg/ml). The exposure to a higher dose of actinomycin (50 μg/ml) caused a decay of chromatoid bodies while nuclear envelopes retained numerous pores. Both the nucleoli and the chromatoid bodies disappeared in the sequential stages. Within the cytoplasm of such cells disintegration of a polysomal pattern was correlated with the disappearance of chromatoid bodies. The significance of the planarian chromatoid body is discussed in relation to differentiation of the regenerative cells. (author)

Downward Slope Driving Control for Electric Powered Wheelchair Based on Capacitor Regenerative Brake

Science.gov (United States)

Seki, Hirokazu; Takahashi, Yoshiaki

This paper describes a novel capacitor regenerative braking control scheme of electric powered wheelchairs for efficient driving on downward slopes. An electric powered wheelchair, which generates the driving force by electric motors, is expected to be widely used as a mobility support system for elderly people and disabled people; however the energy efficiency has to be further improved because it is driven only by battery energy. This study proposes a capacitor regenerative braking circuit and two types of velocity control schemes with variable duty ratio. The proposed regenerative braking circuit is based on the step-up/down circuit with additional resistance and connects right and left motors in series in order to obtain a larger braking power. Some driving experiments on a practical downward slope show the effectiveness of the proposed control system.

New results on performance analysis of opportunistic regenerative relaying

KAUST Repository

Tourki, Kamel; Yang, Hongchuan; Alouini, Mohamed-Slim; Qaraqe, Khalid A.

2013-01-01

In this paper, we investigate an opportunistic relaying scheme where the selected relay assists the source-destination (direct) communication. In our study, we consider a regenerative opportunistic relaying scheme in which the direct path may

Adaptive Regenerative Braking in Electric Vehicles

OpenAIRE

Kubaisi, Rayad

2018-01-01

Elektrofahrzeuge fahren lokal emissionsfrei und tragen damit dazu bei, die Emissionen in Städten zu reduzieren. Zusätzlich, zeichnen sich Elektrofahrzeuge durch ein dynamisches Fahrverhalten aus. Nachteilig wirkt sich bei den meisten Elektrofahrzeugen, die geringe Reichweite auf die Akzeptanz bei Neuwagenkäufern aus. Eine der Maßnahmen zur Erhöhung der Reichweite von Elektrofahrzeuge ist das regenerative Bremsen. Hierbei wird die kinetische Energie des Fahrzeugs durch generatorisches...

MicroRNAs in Tissue Engineering and Regenerative Medicine

NARCIS (Netherlands)

Krenning, Guido; Harmsen, Martin; Sen, Chandan

2015-01-01

The body has a large regenerative capacity to cope with the continuous adverse challenges of high-calorie diets, aging, inflammation, and wear and tear, as well as acute injuries such as myocardial infarction. However, if the amount of sustained damage exceeds the body’s repair capacity,

Human dental pulp stem cells: Applications in future regenerative medicine

Science.gov (United States)

Potdar, Pravin D; Jethmalani, Yogita D

2015-01-01

Stem cells are pluripotent cells, having a property of differentiating into various types of cells of human body. Several studies have developed mesenchymal stem cells (MSCs) from various human tissues, peripheral blood and body fluids. These cells are then characterized by cellular and molecular markers to understand their specific phenotypes. Dental pulp stem cells (DPSCs) are having a MSCs phenotype and they are differentiated into neuron, cardiomyocytes, chondrocytes, osteoblasts, liver cells and β cells of islet of pancreas. Thus, DPSCs have shown great potentiality to use in regenerative medicine for treatment of various human diseases including dental related problems. These cells can also be developed into induced pluripotent stem cells by incorporation of pluripotency markers and use for regenerative therapies of various diseases. The DPSCs are derived from various dental tissues such as human exfoliated deciduous teeth, apical papilla, periodontal ligament and dental follicle tissue. This review will overview the information about isolation, cellular and molecular characterization and differentiation of DPSCs into various types of human cells and thus these cells have important applications in regenerative therapies for various diseases. This review will be most useful for postgraduate dental students as well as scientists working in the field of oral pathology and oral medicine. PMID:26131314

Cooperative Control of Regenerative Braking and Antilock Braking for a Hybrid Electric Vehicle

Directory of Open Access Journals (Sweden)

Guodong Yin

2013-01-01

Full Text Available A new cooperative braking control strategy (CBCS is proposed for a parallel hybrid electric vehicle (HEV with both a regenerative braking system and an antilock braking system (ABS to achieve improved braking performance and energy regeneration. The braking system of the vehicle is based on a new method of HEV braking torque distribution that makes the antilock braking system work together with the regenerative braking system harmoniously. In the cooperative braking control strategy, a sliding mode controller (SMC for ABS is designed to maintain the wheel slip within an optimal range by adjusting the hydraulic braking torque continuously; to reduce the chattering in SMC, a boundary-layer method with moderate tuning of a saturation function is also investigated; based on the wheel slip ratio, battery state of charge (SOC, and the motor speed, a fuzzy logic control strategy (FLC is applied to adjust the regenerative braking torque dynamically. In order to evaluate the performance of the cooperative braking control strategy, the braking system model of a hybrid electric vehicle is built in MATLAB/SIMULINK. It is found from the simulation that the cooperative braking control strategy suggested in this paper provides satisfactory braking performance, passenger comfort, and high regenerative efficiency.

The Hair Follicle: An Underutilized Source of Cells and Materials for Regenerative Medicine.

Science.gov (United States)

Kiani, Mehrdad T; Higgins, Claire A; Almquist, Benjamin D

2018-04-09

The hair follicle is one of only two structures within the adult body that selectively degenerates and regenerates, making it an intriguing organ to study and use for regenerative medicine. Hair follicles have been shown to influence wound healing, angiogenesis, neurogenesis, and harbor distinct populations of stem cells; this has led to cells from the follicle being used in clinical trials for tendinosis and chronic ulcers. In addition, keratin produced by the follicle in the form of a hair fiber provides an abundant source of biomaterials for regenerative medicine. In this review, we provide an overview of the structure of a hair follicle, explain the role of the follicle in regulating the microenvironment of skin and the impact on wound healing, explore individual cell types of interest for regenerative medicine, and cover several applications of keratin-based biomaterials.

Solar sorptive cooling. Technologies, user requirements, practical experience, future prospects

Energy Technology Data Exchange (ETDEWEB)

Treffinger, P. [DLR Deutsches Zentrum fuer Luft- und Raumfahrt e.V., Hardthausen (Germany); Hertlein, H.P. [eds.] [Forschungsverbund Sonnenenergie, Koeln (Germany)

1998-09-01

Sorptive cooling techniques permit the use of low-temperature solar heat, i.e. a renewable energy of low cost and world-wide availability. The Forschungsverbund Sonnenenergie intends to develop solar sorptive cooling technologies to the prototype stage and, in cooperation with the solar industry and its end users, to promote practical application in air conditioning of buildings and cold storage of food. The workshop presents an outline of the state of development of solar sorptive cooling from the view of users and developers. Exemplary solar cooling systems are described, and the potential of open and closed sorptive processes is assessed. Future central activities will be defined in an intensive discussion between planners, producers, users and developers. [German] Der Einsatz von Sorptionstechniken zur Kaelteerzeugung erlaubt es, als treibende Solarenergie Niedertemperatur-Solarwaerme einzusetzen, also eine regenerative Energie mit sehr geringen Kosten und weltweiter Verfuegbarkeit. Der Forschungsverbund Sonnenenergie hat sich als Aufgabe gestellt, die Techniken der solaren Sorptionskuehlung bis zum Prototyp zu entwickeln und mit Industrie und Nutzern die praktische Anwendung voranzubringen. Die Anwendungsfelder sind die Klimatisierung von Gebaeuden und die Kaltlagerung von Lebensmitteln. Der Workshop gibt einen Ueberblick zum Entwicklungsstand der solaren Sorptionskuehlung aus der Sicht der Anwender und Entwickler. Bereits ausgefuehrte Beispiele zur solaren Kuehlung werden vorgestellt und das Potential geschlossener und offener Sorptionsverfahren angegeben. In intensiver Diskussion zwischen Planern, Herstellern, Nutzern und Entwicklern sollen kuenftige Arbeitsschwerpunkte herausgearbeitet werden. (orig.)

Thermo-economic analysis of an integrated solar power generation system using nanofluids

International Nuclear Information System (INIS)

Alashkar, Adnan; Gadalla, Mohamed

2017-01-01

Highlights: • Develop a thermo-economic analysis of an integrated solar-power generation system. • A thermodynamic optimization is proposed to maximize system performance. • Select the optimum nanofluid to replace conventional heating fluids inside a PTSC. • Study the effect of thermal energy storage on performance and cost of the system. • Perform monthly and daily analyses to analyze system behavior using nanofluids. - Abstract: In this paper, a thermo-economic analysis of an Integrated Solar Regenerative Rankine Cycle (ISRRC) is performed. The ISRRC consists of a nanofluid-based Parabolic Trough Solar Collector (PTSC), and a Thermal Energy Storage System (TES) integrated with a Regenerative Rankine Cycle. The effect of dispersing metallic and non-metallic nanoparticles into conventional heating fluids on the output performance and cost of the ISRRC is studied for different volume fractions and for three modes of operation. The first mode assumes no storage, while the second and the third assume a storage system with a storage period of 7.5 h and 10 h respectively. For the modes of operation with the TES, the charging and discharging cycles are explained. The results show that the presence of the nanoparticles leads to an increase in the overall energy produced by the ISRRC for all modes of operation, causing a decrease in the Levelized Cost of Electricity (LEC), and an increase in the net savings of the ISRRC. After comparing the three modes of operation, it is established that the existence of a storage system leads to a higher power generation, and a lower LEC; however, the efficiency of the cycle drops. It is seen that the maximum increase in the annual energy output of the ISRRC caused by the addition of Cu nanoparticles to Syltherm 800 is approximately 3.1%, while the maximum increase in the net savings is about 2.4%.

Cooperative Control of Regenerative Braking and Antilock Braking for a Hybrid Electric Vehicle

OpenAIRE

Yin, Guodong; Jin, XianJian

2013-01-01

A new cooperative braking control strategy (CBCS) is proposed for a parallel hybrid electric vehicle (HEV) with both a regenerative braking system and an antilock braking system (ABS) to achieve improved braking performance and energy regeneration. The braking system of the vehicle is based on a new method of HEV braking torque distribution that makes the antilock braking system work together with the regenerative braking system harmoniously. In the cooperative braking control strategy, a sli...

MicroRNA Delivery for Regenerative Medicine

OpenAIRE

Peng, Bo; Chen, Yongming; Leong, Kam W.

2015-01-01

MicroRNA (miRNA) directs post-transcriptional regulation of a network of genes by targeting mRNA. Although relatively recent in development, many miRNAs direct differentiation of various stem cells including induced pluripotent stem cells (iPSCs), a major player in regenerative medicine. An effective and safe delivery of miRNA holds the key to translating miRNA technologies. Both viral and nonviral delivery systems have seen success in miRNA delivery, and each approach possesses advantages an...

STUDY ON ENERGY EXCHANGE PROCESSES IN NORMAL OPERATION OF METRO ROLLING STOCK WITH REGENERATIVE BRAKING SYSTEMS

Directory of Open Access Journals (Sweden)

A. O. Sulym

2017-10-01

Full Text Available Purpose. The analysis of the existing studies showed that the increasing of energy efficiency of metro rolling stock becomes especially important and requires timely solutions. It is known that the implementation of regenerative braking systems on rolling stock will allow significantly solving this problem. It was proved that one of the key issues regarding the introduction of the above-mentioned systems is research on efficient use of electric energy of regenerative braking. The purpose of the work is to evaluate the amount of excessive electric power of regenerative braking under normal operation conditions of the rolling stock with regenerative braking systems for the analysis of the energy saving reserves. Methodology. Quantifiable values of electrical energy consumed for traction, returned to the contact line and dissipated in braking resistors (excessive energy are determined using results of experimental studies of energy exchange processes under normal operating conditions of metro rolling stock with regenerative systems. Statistical methods of data processing were applied as well. Findings. Results of the studies analysis of metro rolling stock operation under specified conditions in Sviatoshinsko-Brovarskaia line of KP «Kyiv Metro system» stipulate the following: 1 introduction of regenerative braking systems into the rolling stock allows to return about 17.9-23.2% of electrical energy consumed for traction to the contact line; 2 there are reserves for improving of energy efficiency of rolling stock with regenerative systems at the level of 20.2–29.9 % of electrical energy consumed for traction. Originality. For the first time, it is proved that the most significant factor that influences the quantifiable values of the electrical energy regeneration is a track profile. It is suggested to use coefficients which indicate the amount and reserves of unused (excessive electrical energy for quantitative evaluation. Studies on

Technician Marshall MacCready installs solar cells on the Helios Prototype

Science.gov (United States)

2000-01-01

Technician Marshall MacCready carefully lays a panel of solar cells into place on a wing section of the Helios Prototype flying wing at AeroVironment's Design Development Center in Simi Valley, California. The bi-facial cells, manufactured by SunPower, Inc., of Sunnyvale, California, are among 64,000 solar cells which have been installed on the solar-powered aircraft to provide electricity to its 14 motors and operating systems. Developed by AeroVironment under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) project, the Helios Prototype is the forerunner of a planned fleet of slow-flying, long duration, high-altitude aircraft which can perform atmospheric science missions and serve as telecommunications relay platforms in the stratosphere. Target goals set by NASA for the giant 246-foot span flying wing include reaching and sustaining subsonic horizontal flight at 100,000 feet altitude in 2001, and sustained continuous flight for at least four days and nights above 50,000 feet altitude 2003 with the aid of a regenerative fuel cell-based energy storage system now being developed.

Performance Analysis of Regenerative Braking in Permanent Magnet Synchronous Motor Drives

Directory of Open Access Journals (Sweden)

Andrew Adib

2018-02-01

Full Text Available This paper describes the design and analysis of a regenerative braking system for a permanent magnet synchronous motor (PMSM drive for electric vehicle (EV applications. First studied is the principle for electric braking control of a PMSM motor under field-oriented control (FOC. Next, the maximum braking torque in the regeneration mode as well as the braking torque for the maximum regeneration power, respectively, are deduced. Additionally, an optimum switching scheme for the inverter is developed with the objective of maximizing energy recovery during regenerative braking to the DC-bus capacitor. The integration of an ultra-capacitor module with the battery allows for the efficient and high power transfer under regenerative braking. It was important to manage the power flow to the DC-bus as this is a key issue that affects the efficiency of the overall system. Finally, the amounts of braking energy that can be recovered, and the efficiency with which it can be returned to the battery/ultra-capacitor, is analyzed for a PMSM coupled with a DC motor as the load. The results of the analysis are validated through experimentation.

Regenerative braking strategies, vehicle safety and stability control systems: critical use-case proposals

Science.gov (United States)

Oleksowicz, Selim A.; Burnham, Keith J.; Southgate, Adam; McCoy, Chris; Waite, Gary; Hardwick, Graham; Harrington, Cian; McMurran, Ross

2013-05-01

The sustainable development of vehicle propulsion systems that have mainly focused on reduction of fuel consumption (i.e. CO2 emission) has led, not only to the development of systems connected with combustion processes but also to legislation and testing procedures. In recent years, the low carbon policy has made hybrid vehicles and fully electric vehicles (H/EVs) popular. The main virtue of these propulsion systems is their ability to restore some of the expended energy from kinetic movement, e.g. the braking process. Consequently new research and testing methods for H/EVs are currently being developed. This especially concerns the critical 'use-cases' for functionality tests within dynamic events for both virtual simulations, as well as real-time road tests. The use-case for conventional vehicles for numerical simulations and road tests are well established. However, the wide variety of tests and their great number (close to a thousand) creates a need for selection, in the first place, and the creation of critical use-cases suitable for testing H/EVs in both virtual and real-world environments. It is known that a marginal improvement in the regenerative braking ratio can significantly improve the vehicle range and, therefore, the economic cost of its operation. In modern vehicles, vehicle dynamics control systems play the principal role in safety, comfort and economic operation. Unfortunately, however, the existing standard road test scenarios are insufficient for H/EVs. Sector knowledge suggests that there are currently no agreed tests scenarios to fully investigate the effects of brake blending between conventional and regenerative braking as well as the regenerative braking interaction with active driving safety systems (ADSS). The paper presents seven manoeuvres, which are considered to be suitable and highly informative for the development and examination of H/EVs with regenerative braking capability. The critical manoeuvres presented are considered to be

Regenerative Endodontic Treatment: Report of Two Cases with Different Clinical Management and Outcomes

Directory of Open Access Journals (Sweden)

Mehrfam Khoshkhounejad

2015-11-01

Full Text Available Endodontic intervention in necrotic immature permanent teeth is usually a clinical challenge. With appropriate case selection, regenerative treatment can be effective, providing a desirable outcome. However, there is still no consensus on the optimal disinfection protocol or the method to achieve predictable clinical outcome. This article presents two cases of regenerative treatment in necrotic immature teeth, using mineral trioxide aggregate (MTA and BiodentineTM as coronal barriers and different irrigants, which led to different clinical outcomes.

Advances in individualized and regenerative medicine.

Science.gov (United States)

Blum, Hubert E

2014-03-01

Molecular and cell biology have resulted in major advances in our understanding of disease pathogenesis as well as in novel strategies for the diagnosis, therapy and prevention of human diseases. Based on modern molecular, genetic and biochemical methodologies it is on the one hand possible to identify for example disease-related point mutations and single nucleotide polymorphisms. On the other hand, using high throughput array and other technologies, it is for example possible to simultaneously analyze thousands of genes or gene products (RNA and proteins), resulting in an individual gene or gene expression profile ('signature'). Such data increasingly allow to define the individual disposition for a given disease and to predict disease prognosis as well as the efficacy of therapeutic strategies in the individual patient ('individualized medicine'). At the same time, the basic discoveries in cell biology, including embryonic and adult stem cells, induced pluripotent stem cells, genetically modified cells and others, have moved regenerative medicine into the center of biomedical research worldwide with a major translational impact on tissue engineering as well as transplantation medicine. All these aspects have greatly contributed to the recent advances in regenerative medicine and the development novel concepts for the treatment of many human diseases, including liver diseases. Copyright © 2014 Medical University of Bialystok. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

Research on motor rotational speed measurement in regenerative braking system of electric vehicle

Science.gov (United States)

Pan, Chaofeng; Chen, Liao; Chen, Long; Jiang, Haobin; Li, Zhongxing; Wang, Shaohua

2016-01-01

Rotational speed signals acquisition and processing techniques are widely used in rotational machinery. In order to realized precise and real-time control of motor drive and regenerative braking process, rotational speed measurement techniques are needed in electric vehicles. Obtaining accurate motor rotational speed signal will contribute to the regenerative braking force control steadily and realized higher energy recovery rate. This paper aims to develop a method that provides instantaneous speed information in the form of motor rotation. It addresses principles of motor rotational speed measurement in the regenerative braking systems of electric vehicle firstly. The paper then presents ideal and actual Hall position sensor signals characteristics, the relation between the motor rotational speed and the Hall position sensor signals is revealed. Finally, Hall position sensor signals conditioning and processing circuit and program for motor rotational speed measurement have been carried out based on measurement error analysis.

Generation of thyroid follicular cells from pluripotent stem cells: Potential for regenerative medicine

Directory of Open Access Journals (Sweden)

Will eSewell

2014-06-01

Full Text Available Nearly 12 percent of the population in the United States will be afflicted with a thyroid related disorder during their lifetime. Common treatment approaches are tailored to the specific disorder and include surgery, radioactive iodine ablation, antithyroid drugs, thyroid hormone replacement, external beam radiation, and chemotherapy. Regenerative medicine endeavors to combat disease by replacing or regenerating damaged, diseased or dysfunctional body parts. A series of achievements in pluripotent stem cell research have transformed regenerative medicine in many ways by demonstrating repair of a number of body parts in mice, of which, the thyroid has now been inducted into this special group. Seminal work in pluripotent cells, namely embryonic stem cells and induced pluripotent stem cells, have made possible their path to becoming key tools and biological building blocks for cell-based regenerative medicine to combat the gamut of human diseases, including those affecting the thyroid.

Vehicle State Estimator based regenerative braking implementation on an electric vehicle to improve lateral vehicle stability

NARCIS (Netherlands)

Jansen, S.T.H.; van Boekel, J.J.P.; Iersel, van S.S.; Besselink, I.J.M.; Nijmeijer, H.

2013-01-01

The driving range of electric vehicles can be extended using regenerative braking. Regenerative braking uses the electric drive system, and therefore only the driven wheels, for decelerating the vehicle. Braking on one axle affects the stability of the vehicle, especially for road conditions with

Vehicle state estimator based regenerative braking implementation on an electric vehicle to improve lateral vehicle stability

NARCIS (Netherlands)

Jansen, S.T.H.; Boekel, J.J.P. van; Iersel, S.S. van; Besselink, I.J.M.; Nijmeijer, H.

2013-01-01

The driving range of electric vehicles can be extended using regenerative braking. Regenerative braking uses the elctric drive system, and therefore only the driven wheels, for decelerating the vehicle. Braking on one axle affects the stability of the vehicle, especially for road conditions with

Introduction to regenerative medicine and tissue engineering.

Science.gov (United States)

Stoltz, J-F; Decot, V; Huseltein, C; He, X; Zhang, L; Magdalou, J; Li, Y P; Menu, P; Li, N; Wang, Y Y; de Isla, N; Bensoussan, D

2012-01-01

Human tissues don't regenerate spontaneously, explaining why regenerative medicine and cell therapy represent a promising alternative treatment (autologous cells or stem cells of different origins). The principle is simple: cells are collected, expanded and introduced with or without modification into injured tissues or organs. Among middle-term therapeutic applications, cartilage defects, bone repair, cardiac insufficiency, burns, liver or bladder, neurodegenerative disorders could be considered.

Mechanical cues in orofacial tissue engineering and regenerative medicine

NARCIS (Netherlands)

Brouwer, K.M.; Lundvig, D.M.S.; Middelkoop, E.; Wagener, F.A.D.T.; Von den Hoff, J.W.

2015-01-01

Cleft lip and palate patients suffer from functional, aesthetical, and psychosocial problems due to suboptimal regeneration of skin, mucosa, and skeletal muscle after restorative cleft surgery. The field of tissue engineering and regenerative medicine (TE/RM) aims to restore the normal physiology of

Proceedings: Regenerative Medicine for Lung Diseases: A CIRM Workshop Report.

Science.gov (United States)

Kadyk, Lisa C; DeWitt, Natalie D; Gomperts, Brigitte

2017-10-01

The mission of the California Institute of Regenerative Medicine (CIRM) is to accelerate treatments to patients with unmet medical needs. In September 2016, CIRM sponsored a workshop held at the University of California, Los Angeles, to discuss regenerative medicine approaches for treatment of lung diseases and to identify the challenges remaining for advancing such treatments to the clinic and market approval. Workshop participants discussed current preclinical and clinical approaches to regenerative medicine in the lung, as well as the biology of lung stem cells and the role of stem cells in the etiology of various lung diseases. The outcome of this effort was the recognition that whereas transient cell delivery approaches are leading the way in the clinic, recent advances in the understanding of lung stem cell biology, in vitro and in vivo disease modeling, gene editing and replacement methods, and cell engraftment approaches raise the prospect of developing cures for some lung diseases in the foreseeable future. In addition, advances in in vitro modeling using lung organoids and "lung on a chip" technology are setting the stage for high quality small molecule drug screening to develop treatments for lung diseases with complex biology. Stem Cells Translational Medicine 2017;6:1823-1828. © 2017 The Authors Stem Cells Translational Medicine published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

Multifunctional nanodiamonds in regenerative medicine: Recent advances and future directions.

Science.gov (United States)

Whitlow, Jonathan; Pacelli, Settimio; Paul, Arghya

2017-09-10

With recent advances in the field of nanomedicine, many new strategies have emerged for diagnosing and treating diseases. At the forefront of this multidisciplinary research, carbon nanomaterials have demonstrated unprecedented potential for a variety of regenerative medicine applications including novel drug delivery platforms that facilitate the localized and sustained release of therapeutics. Nanodiamonds (NDs) are a unique class of carbon nanoparticles that are gaining increasing attention for their biocompatibility, highly functional surfaces, optical properties, and robust physical properties. Their remarkable features have established NDs as an invaluable regenerative medicine platform, with a broad range of clinically relevant applications ranging from targeted delivery systems for insoluble drugs, bioactive substrates for stem cells, and fluorescent probes for long-term tracking of cells and biomolecules in vitro and in vivo. This review introduces the synthesis techniques and the various routes of surface functionalization that allow for precise control over the properties of NDs. It also provides an in-depth overview of the current progress made toward the use of NDs in the fields of drug delivery, tissue engineering, and bioimaging. Their future outlook in regenerative medicine including the current clinical significance of NDs, as well as the challenges that must be overcome to successfully translate the reviewed technologies from research platforms to clinical therapies will also be discussed. Copyright © 2017 Elsevier B.V. All rights reserved.

New regenerative braking control strategy for rear-driven electrified minivans

International Nuclear Information System (INIS)

Junzhi, Zhang; Yutong, Li; Chen, Lv; Ye, Yuan

2014-01-01

Highlights: • A regenerative braking system is designed for a rear-driven electric minivan. • A new control strategy coordinating energy efficiency and braking feel is proposed. • The control strategy is verified by simulation and hardware-in-loop (HIL) tests. • The proposed control strategy offers higher regeneration efficiency. - Abstract: As of to 2012, minivan ownership stood at 20 million units in China, accounting for 16% of the passenger car market. In this article, comprehensive research is carried out on the design and control of a regenerative braking system for a rear-driven electrified minivan. For improving the regeneration efficiency by as much as possible, a new regenerative braking control strategy called “modified control strategy” is proposed. Additionally, a control strategy called “baseline control strategy” is introduced as a comparative control strategy. Simulations and hardware-in-loop (HIL) tests are carried out. The results of the simulations and the HIL tests show that the modified control strategy offers considerably higher regeneration efficiency than the baseline control strategy. In normal deceleration braking, the regeneration efficiency of the modified control strategy reaches 47%, 15% higher than that of the baseline control strategy. In addition, improvement in the fuel economy of electric vehicles operating on the ECE driving cycle and enhanced with the modified control strategy is greater than 10%, which is 3% higher than that with the baseline control strategy

A single-aliquot OSL protocol using bracketing regenerative doses to accurately determine equivalent doses in quartz

CERN Document Server

Folz, E

1999-01-01

In most cases, sediments show inherent heterogeneity in their luminescence behaviours and bleaching histories, and identical aliquots are not available: single-aliquot determination of the equivalent dose (ED) is then the approach of choice and the advantages of using regenerative protocols are outlined. Experiments on five laboratory bleached and dosed quartz samples, following the protocol described by Murray and Roberts (1998. Measurement of the equivalent dose in quartz using a regenerative-dose single aliquot protocol. Radiation Measurements 27, 171-184), showed the hazards of using a single regeneration dose: a 10% variation in the regenerative dose yielded some equivalent dose estimates that differed from the expected value by more than 5%. A protocol is proposed that allows the use of different regenerative doses to bracket the estimated equivalent dose. The measured ED is found to be in excellent agreement with the known value when the main regeneration dose is within 10% of the true equivalent dose.

A single-aliquot OSL protocol using bracketing regenerative doses to accurately determine equivalent doses in quartz

International Nuclear Information System (INIS)

Folz, Elise; Mercier, Norbert

1999-01-01

In most cases, sediments show inherent heterogeneity in their luminescence behaviours and bleaching histories, and identical aliquots are not available: single-aliquot determination of the equivalent dose (ED) is then the approach of choice and the advantages of using regenerative protocols are outlined. Experiments on five laboratory bleached and dosed quartz samples, following the protocol described by Murray and Roberts (1998. Measurement of the equivalent dose in quartz using a regenerative-dose single aliquot protocol. Radiation Measurements 27, 171-184), showed the hazards of using a single regeneration dose: a 10% variation in the regenerative dose yielded some equivalent dose estimates that differed from the expected value by more than 5%. A protocol is proposed that allows the use of different regenerative doses to bracket the estimated equivalent dose. The measured ED is found to be in excellent agreement with the known value when the main regeneration dose is within 10% of the true equivalent dose

Spacecraft Radiator Freeze Protection Using a Regenerative Heat Exchanger

Science.gov (United States)

Ungar, Eugene K.; Schunk, Richard G.

2011-01-01

An active thermal control system architecture has been modified to include a regenerative heat exchanger (regenerator) inboard of the radiator. Rather than using a radiator bypass valve a regenerative heat exchanger is placed inboard of the radiators. A regenerator cold side bypass valve is used to set the return temperature. During operation, the regenerator bypass flow is varied, mixing cold radiator return fluid and warm regenerator outlet fluid to maintain the system setpoint. At the lowest heat load for stable operation, the bypass flow is closed off, sending all of the flow through the regenerator. This lowers the radiator inlet temperature well below the system set-point while maintaining full flow through the radiators. By using a regenerator bypass flow control to maintain system setpoint, the required minimum heat load to avoid radiator freezing can be reduced by more than half compared to a radiator bypass system.

Integration of regenerative shock absorber into vehicle electric system

Science.gov (United States)

Zhang, Chongxiao; Li, Peng; Xing, Shaoxu; Kim, Junyoung; Yu, Liangyao; Zuo, Lei

2014-03-01

Regenerative/Energy harvesting shock absorbers have a great potential to increase fuel efficiency and provide suspension damping simultaneously. In recent years there's intensive work on this topic, but most researches focus on electricity extraction from vibration and harvesting efficiency improvement. The integration of electricity generated from regenerative shock absorbers into vehicle electric system, which is very important to realize the fuel efficiency benefit, has not been investigated. This paper is to study and demonstrate the integration of regenerative shock absorber with vehicle alternator, battery and in-vehicle electrical load together. In the presented system, the shock absorber is excited by a shaker and it converts kinetic energy into electricity. The harvested electricity flows into a DC/DC converter which realizes two functions: controlling the shock absorber's damping and regulating the output voltage. The damping is tuned by controlling shock absorber's output current, which is also the input current of DC/DC converter. By adjusting the duty cycles of switches in the converter, its input impedance together with input current can be adjusted according to dynamic damping requirements. An automotive lead-acid battery is charged by the DC/DC converter's output. To simulate the working condition of combustion engine, an AC motor is used to drive a truck alternator, which also charges the battery. Power resistors are used as battery's electrical load to simulate in-vehicle electrical devices. Experimental results show that the proposed integration strategy can effectively utilize the harvested electricity and power consumption of the AC motor is decreased accordingly. This proves the combustion engine's load reduction and fuel efficiency improvement.

Preclinical imaging methods for assessing the safety and efficacy of regenerative medicine therapies

Science.gov (United States)

Scarfe, Lauren; Brillant, Nathalie; Kumar, J. Dinesh; Ali, Noura; Alrumayh, Ahmed; Amali, Mohammed; Barbellion, Stephane; Jones, Vendula; Niemeijer, Marije; Potdevin, Sophie; Roussignol, Gautier; Vaganov, Anatoly; Barbaric, Ivana; Barrow, Michael; Burton, Neal C.; Connell, John; Dazzi, Francesco; Edsbagge, Josefina; French, Neil S.; Holder, Julie; Hutchinson, Claire; Jones, David R.; Kalber, Tammy; Lovatt, Cerys; Lythgoe, Mark F.; Patel, Sara; Patrick, P. Stephen; Piner, Jacqueline; Reinhardt, Jens; Ricci, Emanuelle; Sidaway, James; Stacey, Glyn N.; Starkey Lewis, Philip J.; Sullivan, Gareth; Taylor, Arthur; Wilm, Bettina; Poptani, Harish; Murray, Patricia; Goldring, Chris E. P.; Park, B. Kevin

2017-10-01

Regenerative medicine therapies hold enormous potential for a variety of currently incurable conditions with high unmet clinical need. Most progress in this field to date has been achieved with cell-based regenerative medicine therapies, with over a thousand clinical trials performed up to 2015. However, lack of adequate safety and efficacy data is currently limiting wider uptake of these therapies. To facilitate clinical translation, non-invasive in vivo imaging technologies that enable careful evaluation and characterisation of the administered cells and their effects on host tissues are critically required to evaluate their safety and efficacy in relevant preclinical models. This article reviews the most common imaging technologies available and how they can be applied to regenerative medicine research. We cover details of how each technology works, which cell labels are most appropriate for different applications, and the value of multi-modal imaging approaches to gain a comprehensive understanding of the responses to cell therapy in vivo.

[Translational/regulatory science researches of NIHS for regenerative medicine and cellular therapy products].

Science.gov (United States)

Sato, Yoji

2014-01-01

In 2013, the Japanese Diet passed the Regenerative Medicine Promotion Act and the revisions to the Pharmaceutical Affairs Act, which was also renamed as the Therapeutic Products Act (TPA). One of the aims of the new/revised Acts is to promote the development and translation of and access to regenerative/cellular therapies. In the TPA, a product derived from processing cells is categorized as a subgroup of "regenerative medicine, cellular therapy and gene therapy products" (RCGPs), products distinct from pharmaceuticals and medical devices, allowing RCGPs to obtain a conditional and time- limited marketing authorization much earlier than that under the conventional system. To foster not only RCGPs, but also innovative pharmaceuticals and medical devices, the Ministry of Health, Labour and Welfare recently launched Translational Research Program for Innovative Pharmaceuticals, Medical Devices and RCGPs. This mini-review introduces contributions of the National Institute of Health Sciences (NIHS) to research projects on RCGPs in the Program.

Induced Pluripotent Stem Cells for Regenerative Medicine

OpenAIRE

Hirschi, Karen K.; Li, Song; Roy, Krishnendu

2014-01-01

With the discovery of induced pluripotent stem (iPS) cells, it is now possible to convert differentiated somatic cells into multipotent stem cells that have the capacity to generate all cell types of adult tissues. Thus, there is a wide variety of applications for this technology, including regenerative medicine, in vitro disease modeling, and drug screening/discovery. Although biological and biochemical techniques have been well established for cell reprogramming, bioengineering technologies...

Early evaluation and value-based pricing of regenerative medicine technologies.

Science.gov (United States)

Koerber, Florian; Rolauffs, Bernd; Rogowski, Wolf

2013-11-01

Since the first pioneering scientists explored the potential of using human cells for therapeutic purposes the branch of regenerative medicine has evolved to become a mature industry. The focus has switched from 'what can be done' to 'what can be commercialized'. Timely health economic evaluation supports successful marketing by establishing the value of a product from a healthcare system perspective. This article reports results from a research project on early health economic evaluation in collaboration with developers, clinicians and manufacturers. We present an approach to determine an early value-based price for a new treatment of cartilage defects of the knee from the area of regenerative medicine. Examples of using evaluation results for the purpose of business planning, market entry, preparing the coverage decision and managed entry are discussed.

Regenerative medicine through a crisis: social perception and the financial reality.

Science.gov (United States)

Brindley, David; Davie, Natasha

2009-12-01

The aim of this perspective piece is to highlight how the "social perception" and "financial reality" of regenerative medicine may act to hinder its evolution into the principal health-care option for the future. We also consider the role of the consumer and the need for increased public awareness. Furthermore, we consider the effects of the changing social attitudes toward the field, as well as taking into account the influence of current and future political thinking. From a financial viewpoint, we analyze the compatibility of the current venture capital model with regenerative medicine start-ups and explore approaches to ensure sufficient funding and support throughout all stages of product development, for example, the modularization of funding.

Kwantificatie van de invloed van regen op de verkeerdoorstroming

NARCIS (Netherlands)

Calvert, S.C.; Van Stralen, W.; Molin, E.J.E.

2013-01-01

Kwantificatie van de invloed van regen op de verkeerdoorstroming Het is bekend dat het weer invloed heeft op het verkeer op snelwegen, en in het bijzonder filevorming. Op de eerste plaats wordt de wegcapaciteit tijdelijk beïnvloed door een verandering in rijgedrag van bestuurders. Ten tweede

Modeling and Demonstrating Regenerative Braking of a Squirrel Cage Induction Motor with Various Deceleration Rates Using V by F Control

Science.gov (United States)

2010-06-01

dynamics within the regenerative braking process. A discussion was provided regarding the energy within the system during the experiment. F. THESIS ...within the system during the regenerative braking process. Chapter V concludes the thesis with the information gained from the research, and provides...CONCLUSION This thesis explored ideas in which the USN can benefit from energy recovery systems that implements regenerative braking technologies

Optimization of an irreversible Stirling regenerative cycle

International Nuclear Information System (INIS)

Aragón-González, G; Cano-Bianco, M; León-Galicia, A; Rivera-Camacho, J M

2015-01-01

In this work a Stirling regenerative cycle with some irreversibilities is analyzed. The analyzed irreversibilities are located at the heat exchangers. They receive a finite amount of heat and heat leakage occurs between both reservoirs. Using this model, power and the efficiency at maximum power are obtained. Some optimal design parameters for the exchanger heat areas and thermal conductances are presented. The relation between the power, efficiency and the results obtained are shown graphically

Study on Differential Regenerative Braking Torque Control to Increase the Stability of the Small Electric Vehicle with Four In-Wheel Motors

Directory of Open Access Journals (Sweden)

Ali N. M.

2017-01-01

Full Text Available Based on the advantages of the electric motor such as fast and precise torque response, the performance of the electric vehicle (EV can be improved. During braking or driving on the cornering, the vehicle will over steer or under steer if a car turns by more or less than the amount commanded by the driver. To improve the stability of the small EV with four in-wheel motors, the differential regenerative braking torque control is proposed. In this system, the regenerative braking torque at each wheel will be controlled individually based on the value of slip ratio. If the slip ratio is greater than the optimum value, the regenerative brake will turn off. In this situation, the electric motor will not produce the regenerative braking torque. Conversely, if the slip ratio lower than the optimum value, the regenerative brake will turn on and the electric motor will generate the regenerative braking torque. In the numerical analysis, to investigate the effectiveness of the proposed model, the road condition is set to an icy road on the left tire and dry asphalt on the right tire. From the simulation results, the differential regenerative braking torque control can prevent the tire from lock-up and avoid the vehicle from skidding.

Regenerative therapy and tissue engineering for the treatment of end-stage cardiac failure

Science.gov (United States)

Finosh, G.T.; Jayabalan, Muthu

2012-01-01

Regeneration of myocardium through regenerative therapy and tissue engineering is appearing as a prospective treatment modality for patients with end-stage heart failure. Focusing on this area, this review highlights the new developments and challenges in the regeneration of myocardial tissue. The role of various cell sources, calcium ion and cytokine on the functional performance of regenerative therapy is discussed. The evolution of tissue engineering and the role of tissue matrix/scaffold, cell adhesion and vascularisation on tissue engineering of cardiac tissue implant are also discussed. PMID:23507781

Phosphorous-Containing Polymers for Regenerative Medicine

Science.gov (United States)

Watson, Brendan M.; Kasper, F. Kurtis; Mikos, Antonios G.

2014-01-01

Disease and injury have resulted in a large, unmet need for functional tissue replacements. Polymeric scaffolds can be used to deliver cells and bioactive signals to address this need for regenerating damaged tissue. Phosphorous-containing polymers have been implemented to improve and accelerate the formation of native tissue both by mimicking the native role of phosphorous groups in the body and by attachment of other bioactive molecules. This manuscript reviews the synthesis, properties, and performance of phosphorous-containing polymers that can be useful in regenerative medicine applications. PMID:24565855

Bioprinting is changing regenerative medicine forever.

Science.gov (United States)

Collins, Scott Forrest

2014-12-01

3D printing, or solid freeform fabrication, applied to regenerative medicine brings technologies from several industries together to help solve unique challenges in both basic science and tissue engineering. By more finely organizing cells and supporting structures precisely in 3D space, we will gain critical knowledge of cell-cell communications and cell-environment interactions. As we increase the scale, we will move toward complex tissue and organ structures where several cell phenotypes will functionally and structurally interact, thus recapitulating the form and function of native tissues and organs.

Tissue engineering and regenerative medicine in applied research: a year in review of 2014.

Science.gov (United States)

Lin, Xunxun; Huang, Jia; Shi, Yuan; Liu, Wei

2015-04-01

Tissue engineering and regenerative medicine (TERM) remains to be one of the fastest growing fields, which covers a wide scope of topics of both basic and applied biological researches. This overview article summarized the advancements in applied researches of TERM area, including stem cell-mediated tissue regeneration, material science, and TERM clinical trial. These achievements demonstrated the great potential of clinical regenerative therapy of tissue/organ disease or defect through stem cells and tissue engineering approaches.

Capacitor regenerative braking system of electric wheelchair for senior citizen based on variable frequency chopper control.

Science.gov (United States)

Takahashi, Yoshiaki; Seki, Hirokazu

2009-01-01

This paper proposes a novel regenerative braking control system of electric wheelchairs for senior citizen. "Electric powered wheelchair", which generates the driving force by electric motors according to the human operation, is expected to be widely used as a mobility support system for elderly people. This study focuses on the braking control to realize the safety and smooth stopping motion using the regenerative braking control technique based on fuzzy algorithm. The ride quality improvement and energy recycling can be expected by the proposed control system with stopping distance estimation and variable frequency control on the step-up/down chopper type of capacitor regenerative circuit. Some driving experiments confirm the effectiveness of the proposed control system.

Hydrogen-Oxygen PEM Regenerative Fuel Cell at NASA Glenn Research Center

Science.gov (United States)

Bents, David J.

2004-01-01

The NASA Glenn Research Center has constructed a closed-cycle hydrogen-oxygen PEM regenerative fuel cell (RFC) to explore its potential use as an energy storage device for a high altitude solar electric aircraft. Built up over the last 2 years from specialized hardware and off the shelf components the Glenn RFC is a complete "brassboard" energy storage system which includes all the equipment required to (1) absorb electrical power from an outside source and store it as pressurized hydrogen and oxygen and (2) make electrical power from the stored gases, saving the product water for re-use during the next cycle. It consists of a dedicated hydrogen-oxygen fuel cell stack and an electrolyzer stack, the interconnecting plumbing and valves, cooling pumps, water transfer pumps, gas recirculation pumps, phase separators, storage tanks for oxygen (O2) and hydrogen (H2), heat exchangers, isolation valves, pressure regulators, nitrogen purge provisions, instrumentation, and other components. It specific developmental functions include: (1) Test fuel cells and fuel cell components under repeated closed-cycle operation (nothing escapes; everything is used over and over again). (2) Simulate diurnal charge-discharge cycles (3) Observe long-term system performance and identify degradation and loss mechanisms. (4) Develop safe and convenient operation and control strategies leading to the successful development of mission-capable, flight-weight RFC's.

Use of regenerative energy sources and hydrogen technology 2006. Proceedings

International Nuclear Information System (INIS)

Lehmann, J.; Luschtinetz, T.

2006-01-01

This volume contains 25 contributions, which were held on the 13th symposium ''Use of regenerative energy sources and hydrogen technology'' in Stralsund (Germany). Separate documentation items analysing 16 of the contributions have been prepared for the ENERGY database

Waste heat recovery for transport trucks using thermally regenerative fuel cells

Energy Technology Data Exchange (ETDEWEB)

Carrier, A.; Wechsler, D.; Whitney, R.; Jessop, P. [Queen' s Univ., Kingston, ON (Canada). Dept. of Chemistry; Davis, B.R. [Queen' s-RMC Fuel Cell Research Centre, Kingston, ON (Canada)

2009-07-01

Carbon emissions associated with transportation can be reduced by increasing the fuel efficiency of transport trucks. This can be achieved with thermally regenerative fuel cells that transform the waste heat from the engine block into electricity. In order to operate such a fuel cell, one needs a fluid which rapidly, reversibly, and selectively undergoes dehydrogenation. Potential fluids have been screened for their ability to dehydrogenate and then rehydrogenate at the appropriate temperatures. An examination of the thermodynamics, kinetics, and selectivities of these processes have shown that the challenge involving hydrogenolysis at high temperature must be addressed. This paper discussed the economics of thermally regenerative fuel cells and the advantages and disadvantages of the identified fluids, and of such systems in general.

Regenerative medicine in India: trends and challenges in innovation and regulation.

Science.gov (United States)

Tiwari, Shashank S; Raman, Sujatha; Martin, Paul

2017-10-01

The government of India has heavily promoted research and development in regenerative medicine together with domestic innovation and business development initiatives. Together, these promise a revolution in healthcare and public empowerment in India. Several national and transnational linkages have emerged to develop innovative capacity, most prominently in stem cell and cord blood banking, as well as in gene therapy, tissue engineering, biomaterials and 3D printing. However, challenges remain of achieving regulatory oversight, viable outputs and equitable impacts. Governance of private cord blood banking, nanomaterials and 3D bioprinting requires more attention. A robust social contract is also needed in healthcare more generally, so that participation in research and innovation in regenerative medicine is backed up by treatments widely accessible to all.

Multiple infarcted regenerative nodules in liver cirrhosis after decompensation of cirrhosis: a case series

Directory of Open Access Journals (Sweden)

Müllhaupt Beat

2010-11-01

Full Text Available Abstract Introduction Liver cirrhosis is a common disease with many known complications. Cirrhosis represents a clinical spectrum, ranging from asymptomatic liver disease to hepatic decompensation. Manifestations of hepatic decompensation include variceal bleeding, ascites, hepatic encephalopathy, hepatorenal syndrome, hepatopulmonary syndrome, portopulmonary hypertension and hepatocellular carcinoma. There are reports about infarcted regenerative nodules in cirrhotic livers after gastrointestinal hemorrhage. Case presentation We report three Caucasian patients (one female and two male patients; ages: 52, 54 and 60 years with decompensated liver cirrhosis, who showed newly infarcted regenerative nodules at necropsy. Two of them suffered from gastric variceal bleeding. Histopathology showed extensive infarction in all three cases. Hemorrhage and inflammatory changes were also observed around the infarcted regenerative nodules. Conclusion These patients showed focal liver lesions, to be considered in the differential diagnosis of cirrhotic livers. Infarcted regenerative nodules may be underdiagnosed in patients with decompensation of cirrhosis. In order to differentiate these lesions from malignant tumors, serial imaging seems to be helpful. However, the main differential diagnosis should be an abscess. It is important to know the wide spectrum of image appearances of these lesions. Hypotension can lead to a reduction of portal and arterial liver flow. Since variceal bleeding or septic shock can induce hypotension - as observed in our patients - we conclude that this leads to infarction of such nodules.

Thermodynamic analysis of high-temperature regenerative organic Rankine cycles using siloxanes as working fluids

International Nuclear Information System (INIS)

Fernandez, F.J.; Prieto, M.M.; Suarez, I.

2011-01-01

A recent novel adjustment of the Span-Wagner equation of state for siloxanes, used as working fluids in high-temperature organic Rankine cycles, is applied in a mathematical model to solve cycles under several working conditions. The proposed scheme includes a thermo-oil intermediate heat circuit between the heat source and the organic Rankine cycle. Linear and cyclic siloxanes are assayed in saturated, superheated and supercritical cycles. The cycle includes an internal heat exchanger (regenerative cycle), although a non-regenerative scheme is also solved. In the first part of the study, a current of combustion gases cooled to close to their dew point temperature is taken as the reference heat source. In the second part, the outlet temperature of the heat source is varied over a wide range, determining appropriate fluids and schemes for each thermal level. Simple linear (MM, MDM) siloxanes in saturated regenerative schemes show good efficiencies and ensure thermal stability of the working fluid. -- Highlights: → Organic Rankine cycles with polymethylsiloxanes as working fluids were modelled. → The cycle scheme is regenerative and includes an intermediate heat transfer fluid. → The fluid properties were calculated by means of the Span-Wagner equation of state. → Vapour conditions to the expander and source thermal level were analysed. → Siloxanes MM, MDM and D 4 under saturated conditions were the best options.

Regeneration-associated macrophages: a novel approach to boost intrinsic regenerative capacity for axon regeneration

Directory of Open Access Journals (Sweden)

Min Jung Kwon

2016-01-01

Full Text Available Axons in central nervous system (CNS do not regenerate spontaneously after injuries such as stroke and traumatic spinal cord injury. Both intrinsic and extrinsic factors are responsible for the regeneration failure. Although intensive research efforts have been invested on extrinsic regeneration inhibitors, the extent to which glial inhibitors contribute to the regeneration failure in vivo still remains elusive. Recent experimental evidence has rekindled interests in intrinsic factors for the regulation of regeneration capacity in adult mammals. In this review, we propose that activating macrophages with pro-regenerative molecular signatures could be a novel approach for boosting intrinsic regenerative capacity of CNS neurons. Using a conditioning injury model in which regeneration of central branches of dorsal root ganglia sensory neurons is enhanced by a preceding injury to the peripheral branches, we have demonstrated that perineuronal macrophages surrounding dorsal root ganglia neurons are critically involved in the maintenance of enhanced regeneration capacity. Neuron-derived chemokine (C-C motif ligand 2 (CCL2 seems to mediate neuron-macrophage interactions conveying injury signals to perineuronal macrophages taking on a soley pro-regenerative phenotype, which we designate as regeneration-associated macrophages (RAMs. Manipulation of the CCL2 signaling could boost regeneration potential mimicking the conditioning injury, suggesting that the chemokine-mediated RAM activation could be utilized as a regenerative therapeutic strategy for CNS injuries.

Adaptive regenerative braking for electric vehicles with an electric motor at the front axle using the state dependent Riccati equation control technique

NARCIS (Netherlands)

Jansen, S.; Alirezaei, M.; Kanarachos, S.

2014-01-01

In this paper a novel adaptive regenerative braking control concept for electric vehicles with an electric motor at the front axle is presented. It is well known that the "phased" type regenerative braking systems of category B maximize the amount of regenerative energy during braking. However,

MRI tracking of SPIO labelled stem cells in a true regenerative environment, the regenerating limb of the axolotl

DEFF Research Database (Denmark)

Lauridsen, Henrik; Foldager, Casper Bindzus; Hagensen, Mette

are generally restricted by their limited regenerative potential. Conversely, excellent animal models for regenerative studies exist in lower vertebrates such as the urodele amphibians (salamanders and newts), exemplified in the iconic Mexican axolotl (Ambystoma mexicanum) capable of regenerating whole limbs...

Analysis of a Hybrid Mechanical Regenerative Braking System

Directory of Open Access Journals (Sweden)

Toh Xiang Wen Matthew

2018-01-01

Full Text Available Regenerative braking systems for conventional vehicles are gaining attention as fossil fuels continue to be depleted. The major forms of regenerative braking systems include electrical and mechanical systems, with the former being more widely adopted at present. However mechanical systems are still feasible, including the possible hybrid systems of two mechanical energy recovery systems. A literature study was made to compare the various mechanical energy recovery systems. These systems were compared based on their advantages and disadvantages with regards to energy storage, usage, and maintenance. Based on the comparison, the most promising concept appeared to be one that combined the flywheel and the pneumatic energy recovery systems. A CAD model of this hybrid system was produced to better visualise the design. This was followed by analytical modelling of the energy recovery systems. The analysis indicated that the angular velocity had an extremely significant impact on the power loss and energy efficiency. The results showed that the hybrid system can provide better efficiency but only when operating within certain parameters. Future work is required to further improve the efficiency of this hybrid system.

Regenerative Medicine: Solution in Sight.

Science.gov (United States)

Wang, Qingjie; Stern, Jeffrey H; Temple, Sally

2016-01-01

The retina, like other central nervous system tissues, has poor regenerative properties in humans. Therefore, diseases that cause retinal cell loss, such as Age-related macular degeneration (AMD), retinitis pigmentosa (RP), Leber congenital amaurosis, Usher syndrome, glaucoma, and diabetic retinopathy, typically result in permanent visual impairment. Stem cell technologies have revolutionized our ability to produce neural cells in abundant supply. Much stem cell research effort is focused on producing the required cell types for cell replacement, or to generate disease-in-a-dish models to elucidate novel disease mechanisms for therapeutic development. Here we review the recent advances in stem cell studies relevant to producing RPE and retinal cells, and highlight future directions.

Methodology of heat transfer and flow resistance measurement for matrices of rotating regenerative heat exchangers

Directory of Open Access Journals (Sweden)

Butrymowicz Dariusz

2016-09-01

Full Text Available The theoretical basis for the indirect measurement approach of mean heat transfer coefficient for the packed bed based on the modified single blow technique was presented and discussed in the paper. The methodology of this measurement approach dedicated to the matrix of the rotating regenerative gas heater was discussed in detail. The testing stand consisted of a dedicated experimental tunnel with auxiliary equipment and a measurement system are presented. Selected experimental results are presented and discussed for selected types of matrices of regenerative air preheaters for the wide range of Reynolds number of gas. The agreement between the theoretically predicted and measured temperature profiles was demonstrated. The exemplary dimensionless relationships between Colburn heat transfer factor, Darcy flow resistance factor and Reynolds number were presented for the investigated matrices of the regenerative gas heater.

Regenerative medicine using dental pulp stem cells for liver diseases.

Science.gov (United States)

Ohkoshi, Shogo; Hara, Hajime; Hirono, Haruka; Watanabe, Kazuhiko; Hasegawa, Katsuhiko

2017-02-06

Acute liver failure is a refractory disease and its prognosis, if not treated using liver transplantation, is extremely poor. It is a good candidate for regenerative medicine, where stem cell-based therapies play a central role. Mesenchymal stem cells (MSCs) are known to differentiate into multiple cell lineages including hepatocytes. Autologous cell transplant without any foreign gene induction is feasible using MSCs, thereby avoiding possible risks of tumorigenesis and immune rejection. Dental pulp also contains an MSC population that differentiates into hepatocytes. A point worthy of special mention is that dental pulp can be obtained from deciduous teeth during childhood and can be subsequently harvested when necessary after deposition in a tooth bank. MSCs have not only a regenerative capacity but also act in an anti-inflammatory manner via paracrine mechanisms. Promising efficacies and difficulties with the use of MSC derived from teeth are summarized in this review.

Tissue engineering and regenerative medicine: manufacturing challenges.

Science.gov (United States)

Williams, D J; Sebastine, I M

2005-12-01

Tissue engineering and regenerative medicine are interdisciplinary fields that apply principles of engineering and life sciences to develop biological substitutes, typically composed of biological and synthetic components, that restore, maintain or improve tissue function. Many tissue engineering technologies are still at a laboratory or pre-commercial scale. The short review paper describes the most significant manufacturing and bio-process challenges inherent in the commercialisation and exploitation of the exciting results emerging from the biological and clinical laboratories exploring tissue engineering and regenerative medicine. A three-generation road map of the industry has been used to structure a view of these challenges and to define where the manufacturing community can contribute to the commercial success of the products from these emerging fields. The first-generation industry is characterised by its demonstrated clinical applications and products in the marketplace, the second is characterised by emerging clinical applications, and the third generation is characterised by aspirational clinical applications. The paper focuses on the cost reduction requirement of the first generation of the industry to allow more market penetration and consequent patient impact. It indicates the technological requirements, for instance the creation of three-dimensional tissue structures, and value chain issues in the second generation of the industry. The third-generation industry challenges lie in fundamental biological and clinical science. The paper sets out a road map of these generations to identify areas for research.

Urban agriculture as one of the ecological applications of the regenerative city

Directory of Open Access Journals (Sweden)

وفل جوزيف رزقو

2017-09-01

Full Text Available Recently, several concepts and expressions have emerged that have often preoccupied the world . around the concept of environment and sustainability. This is due to the negative and irresponsible impact of man and his innovations in various industrial and technological fieldsthat have damaged the natural environment. Architecture and cities at the broader level are some of the man made components that caused these negative impacts and in the same time affected by them. What distinguishes architectural and urban projects is the consumption of large . quantities of natural resources and production larger amounts of waste and pollution, along the life of these projects. At the end of the twentieth century and the beginning of the twenty-first century, the developed countries presented new concepts and methods that were not previously familiar with the design and implementation of architectural projects to reflect the growing interest in urban sectors issues to protect the environment and reduce consumption to reach the optimal utilization of natural resources. This leads to develop a new term called the Regenerative City. Here appeared the general research problem concerning the regenerative city and its objectives and the special research problem concerning urban agriculture and its relationship with the regenerative city, besides how urban agriculture will affect the city. The hypothesis of the research is that urban agriculture in its various forms (horizontal or vertical is an essential and integral part of the regenerative city, and it will affect the city planning, this will require including this usage in the city master plan as a new form of land use. The research aims to show the possibilities of using urban agriculture in its different forms within the urban fabric.

Advances in stem cells and regenerative medicine: single-cell dynamics, new models and translational perspectives.

Science.gov (United States)

Twigger, Alecia-Jane; Scheel, Christina H

2017-09-01

An international cohort of over 300 stem cell biologists came together in Heidelberg, Germany in May 2017 as delegates of the 'Advances in Stem Cells and Regenerative Medicine' conference run through the European Molecular Biology Organization. This Meeting Review highlights the novel insights into stem cell regulation, new technologies aiding in discovery and exciting breakthroughs in the field of regenerative medicine that emerged from the meeting. © 2017. Published by The Company of Biologists Ltd.

Research on Modeling and Control of Regenerative Braking for Brushless DC Machines Driven Electric Vehicles

OpenAIRE

Jian-ping Wen; Chuan-wei Zhang

2015-01-01

In order to improve energy utilization rate of battery-powered electric vehicle (EV) using brushless DC machine (BLDCM), the model of braking current generated by regenerative braking and control method are discussed. On the basis of the equivalent circuit of BLDCM during the generative braking period, the mathematic model of braking current is established. By using an extended state observer (ESO) to observe actual braking current and the unknown disturbances of regenerative braking system, ...

Budd-Chiari syndrome and secondary nodular regenerative hyperplasia of the liver. Case report with special reference to diagnostic imaging

International Nuclear Information System (INIS)

Mutze, A.; Rueckert, R.; Rudolph, B.; Paris, S.; Podrabski, P.

1993-01-01

Nodular regenerative hyperplasia is a benign epithelial proliferation of the liver with unknown etiology. We observed a female patient with Budd-Chiari syndrome and secondary nodular regenerative hyperplasia of the liver over a period of five years. Patient history, diagnostic imaging (sonography, CT, MR imaging, angiography), and clinical course are demonstrated along with results of macroscopic and microscopic studies of explanted liver prior to liver transplantation. The patient presented with various predisposing factors in combination that favour the development of nodular regenerative hyperplasia. (orig.) [de

Coordination of Regenerative Relays and Direct Users in Wireless Cellular Networks

DEFF Research Database (Denmark)

Thai, Chan; Popovski, Petar

2011-01-01

The area of wireless cooperation/relaying has recently been significantly enriched by the ideas of wireless network coding (NC), which bring substantial gains in spectral efficiency. These gains have mainly been demonstrated in scenarios with two-way relaying. Inspired by the ideas of wireless NC......, recently we have proposed techniques for coordinated direct/relay (CDR) transmissions. These techniques embrace the interference among the communication flows to/from direct and relayed users, leveraging on the fact that the interference can be subsequently canceled. Hence, by allowing simultaneous...... transmissions, spectral efficiency is increased. In our prior work, we have considered CDR with non-regenerative relay that uses Amplify-and-Forward (AF). In this paper we consider the case of regenerative Decode-and-Forward (DF) relay. This refers also to joint decoding of the interfering flows received over...

A case of non-regenerative immune-mediated anemia treated by ...

African Journals Online (AJOL)

A 12-year-old female Shih Tzu dog was referred with diarrhea. Hematological examination indicated severe nonregenerative anemia. Bone marrow aspiration smears and core biopsy specimens revealed normal bone marrow. Based on those results, non-regenerative immune mediated anemia was diagnosed. The dog ...

Three-dimensional bioprinting of stem-cell derived tissues for human regenerative medicine.

Science.gov (United States)

Skeldon, Gregor; Lucendo-Villarin, Baltasar; Shu, Wenmiao

2018-07-05

Stem cell technology in regenerative medicine has the potential to provide an unlimited supply of cells for drug testing, medical transplantation and academic research. In order to engineer a realistic tissue model using stem cells as an alternative to human tissue, it is essential to create artificial stem cell microenvironment or niches. Three-dimensional (3D) bioprinting is a promising tissue engineering field that offers new opportunities to precisely place stem cells within their niches layer-by-layer. This review covers bioprinting technologies, the current development of 'bio-inks' and how bioprinting has already been applied to stem-cell culture, as well as their applications for human regenerative medicine. The key considerations for bioink properties such as stiffness, stability and biodegradation, biocompatibility and printability are highlighted. Bioprinting of both adult and pluriopotent stem cells for various types of artificial tissues from liver to brain has been reviewed. 3D bioprinting of stem-cell derived tissues for human regenerative medicine is an exciting emerging area that represents opportunities for new research, industries and products as well as future challenges in clinical translation.This article is part of the theme issue 'Designer human tissue: coming to a lab near you'. © 2018 The Author(s).

Influence of System Parameters on Fuse Protection Use in Regenerative DC Drives

Directory of Open Access Journals (Sweden)

Isa Salman Qamber

2009-06-01

Full Text Available Current limiting fuses are widely used to protect the thyristors in DC drive systems. One very important problem is the choice of the correct voltage rating for fuses protecting regenerative DC drives, where many types of fault may occur, which makes fuse protection difficult. In the event of a commutation failure while regenerating, the fuses need to interrupt the loop supplied by the AC and DC voltages acting in series, which is the most difficult case for protection by fuses. In this paper a detailed study of the complete interruption process has been investigated by modeling of arcing process of the fuse protection against the regenerative circuit internal commutation fault. The effect of varying the motor time constant, supply impedance, number of fuses used to clear the fault and DC machine rating on the total transient response is studied. The model of a 200 A fuse is employed in this study. Fuses in series with both the semiconductor devices (F1 and fuses in AC lines (F2 are considered. Comparison was made between arc energy produced for fuses protecting the regenerative circuit if failure occurs, with the arc energy produced in a standard AC test in order to investigate the required voltage rating for the fuse.

Micro-computed tomography (CT) based assessment of dental regenerative therapy in the canine mandible model

Science.gov (United States)

Khobragade, P.; Jain, A.; Setlur Nagesh, S. V.; Andreana, S.; Dziak, R.; Sunkara, S. K.; Sunkara, S.; Bednarek, D. R.; Rudin, S.; Ionita, C. N.

2015-03-01

High-resolution 3D bone-tissue structure measurements may provide information critical to the understanding of the bone regeneration processes and to the bone strength assessment. Tissue engineering studies rely on such nondestructive measurements to monitor bone graft regeneration area. In this study, we measured bone yield, fractal dimension and trabecular thickness through micro-CT slices for different grafts and controls. Eight canines underwent surgery to remove a bone volume (defect) in the canine's jaw at a total of 44 different locations. We kept 11 defects empty for control and filled the remaining ones with three regenerative materials; NanoGen (NG), a FDA-approved material (n=11), a novel NanoCalcium Sulfate (NCS) material (n=11) and NCS alginate (NCS+alg) material (n=11). After a minimum of four and eight weeks, the canines were sacrificed and the jaw samples were extracted. We used a custombuilt micro-CT system to acquire the data volume and developed software to measure the bone yield, fractal dimension and trabecular thickness. The software used a segmentation algorithm based on histograms derived from volumes of interest indicated by the operator. Using bone yield and fractal dimension as indices we are able to differentiate between the control and regenerative material (p<0.005). Regenerative material NCS showed an average 63.15% bone yield improvement over the control sample, NCS+alg showed 55.55% and NanoGen showed 37.5%. The bone regeneration process and quality of bone were dependent upon the position of defect and time period of healing. This study presents one of the first quantitative comparisons using non-destructive Micro-CT analysis for bone regenerative material in a large animal with a critical defect model. Our results indicate that Micro-CT measurement could be used to monitor invivo bone regeneration studies for greater regenerative process understanding.

Emdogain in regenerative periodontal therapy. A review of the literature.

NARCIS (Netherlands)

Sculean, A.; Windisch, P.; Dori, F.; Keglevich, T.; Molnar, B.; Gera, I.

2007-01-01

The goal of regenerative periodontal therapy is the reconstitution of the lost periodontal structures (i.e. the new formation of root cementum, periodontal ligament and alveolar bone). Results from basic research have pointed to the important role of the enamel matrix protein derivative (EMD) in the

Conditional approval: Japan lowers the bar for regenerative medicine products.

Science.gov (United States)

Sipp, Douglas

2015-04-02

A new system for conditional approval of regenerative medicine products will allow products of undetermined efficacy to enter the Japanese market. The potential scientific, economic, and ethical implications of this program highlight the need for further discussion and refinement. Copyright © 2015 Elsevier Inc. All rights reserved.

Effective use of solar and biogas energy technology in companies

Energy Technology Data Exchange (ETDEWEB)

Duerr-Pucher, J. [Clean Energy, Radolfzell (Germany)

2006-07-01

Summary: In Germany and Europe the use of biogas and solar energy technology in enterprises is still in its infancy. The high growth rate of biogas and solar energy power is due to investments made by private households and agriculture. For medium-sized enterprises and large-scale enterprises the investment conditions obviously are not attractive enough, with one exception: enterprises that are manufacturing solar installations and offer, as a second pillar, concepts for their economical operation. Since the amendment of the EEG the demand for biogas installations considerably increased - exclusively in the agricultural sector. Enterprises from the food and beverage sector for instance only slowly discover this market. In the photovoltaic sector the situation is quite different. A real boom started 1998 in Germany. Main investors are farmers just as in the biogas area because their houses often have large roof surfaces and they can purchase via special associations large quantities of solar modules. The second important factor is the demand of ecologically oriented private households for small installations. Very seldom it is possible to motivate enterprises to equip the roofs of their plants with photovoltaic cells. It depends on the ecological orientation of enterprises and on communicative aspects. An early example is Mercedes-Benz. In 1995, world's largest photovoltaic solar power plant was installed in Untertuerkheim. Currently there are only a few industrial solar thermal model projects. In 2006, a medium-sized brewery has set up world's first 'solar' brewing plant. Contrary to the photovoltaic sector manufacturers of solar thermal systems must at first develop sustainable concepts. In contrast to the EEG (Renewable Energy Sources Act) for electricity generation there is no legal basis for solar thermal systems. Many European countries (Spain, Italy, Greece) have adopted regulations similarly to EEG. An expansion of the use of regenerative

Biomaterials and Culture Technologies for Regenerative Therapy of Liver Tissue.

Science.gov (United States)

Perez, Roman A; Jung, Cho-Rok; Kim, Hae-Won

2017-01-01

Regenerative approach has emerged to substitute the current extracorporeal technologies for the treatment of diseased and damaged liver tissue. This is based on the use of biomaterials that modulate the responses of hepatic cells through the unique matrix properties tuned to recapitulate regenerative functions. Cells in liver preserve their phenotype or differentiate through the interactions with extracellular matrix molecules. Therefore, the intrinsic properties of the engineered biomaterials, such as stiffness and surface topography, need to be tailored to induce appropriate cellular functions. The matrix physical stimuli can be combined with biochemical cues, such as immobilized functional groups or the delivered actions of signaling molecules. Furthermore, the external modulation of cells, through cocultures with nonparenchymal cells (e.g., endothelial cells) that can signal bioactive molecules, is another promising avenue to regenerate liver tissue. This review disseminates the recent approaches of regenerating liver tissue, with a focus on the development of biomaterials and the related culture technologies. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The Impact of Biomechanics in Tissue Engineering and Regenerative Medicine

Science.gov (United States)

Butler, David L.; Goldstein, Steven A.; Guo, X. Edward; Kamm, Roger; Laurencin, Cato T.; McIntire, Larry V.; Mow, Van C.; Nerem, Robert M.; Sah, Robert L.; Soslowsky, Louis J.; Spilker, Robert L.; Tranquillo, Robert T.

2009-01-01

Biomechanical factors profoundly influence the processes of tissue growth, development, maintenance, degeneration, and repair. Regenerative strategies to restore damaged or diseased tissues in vivo and create living tissue replacements in vitro have recently begun to harness advances in understanding of how cells and tissues sense and adapt to their mechanical environment. It is clear that biomechanical considerations will be fundamental to the successful development of clinical therapies based on principles of tissue engineering and regenerative medicine for a broad range of musculoskeletal, cardiovascular, craniofacial, skin, urinary, and neural tissues. Biomechanical stimuli may in fact hold the key to producing regenerated tissues with high strength and endurance. However, many challenges remain, particularly for tissues that function within complex and demanding mechanical environments in vivo. This paper reviews the present role and potential impact of experimental and computational biomechanics in engineering functional tissues using several illustrative examples of past successes and future grand challenges. PMID:19583462

Human neonatal cardiovascular progenitors: unlocking the secret to regenerative ability.

Directory of Open Access Journals (Sweden)

Tania I Fuentes

Full Text Available Although clinical benefit can be achieved after cardiac transplantation of adult c-kit+ or cardiosphere-derived cells for myocardial repair, these stem cells lack the regenerative capacity unique to neonatal cardiovascular stem cells. Unraveling the molecular basis for this age-related discrepancy in function could potentially transform cardiovascular stem cell transplantation. In this report, clonal populations of human neonatal and adult cardiovascular progenitor cells were isolated and characterized, revealing the existence of a novel subpopulation of endogenous cardiovascular stem cells that persist throughout life and co-express both c-kit and isl1. Epigenetic profiling identified 41 microRNAs whose expression was significantly altered with age in phenotypically-matched clones. These differences were correlated with reduced proliferation and a limited capacity to invade in response to growth factor stimulation, despite high levels of growth factor receptor on progenitors isolated from adults. Further understanding of these differences may provide novel therapeutic targets to enhance cardiovascular regenerative capacity.

Regenerative endodontics--biologically-based treatment for immature permanent teeth: a case report and review of the literature.

Science.gov (United States)

Thomson, A; Kahler, B

2010-12-01

A paradigm shift in the treatment of immature, necrotic teeth has occurred with biologically-based principles and regenerative endodontic protocols replacing traditional 'apexification' procedures. Preliminary research suggests that stem and progenitor cells from the pulp and/or periodontium contribute to continued root development when regenerative procedures are followed. A mandibular premolar tooth with a chronic periapical abscess was irrigated with sodium hypochlorite with minimal instrumentation and then dressed with tri-antibiotic paste consisting of ciprofloxacin, metronidazole and amoxicillin. At a subsequent visit a blood clot was evoked in the canal by irritating periapical tissues and the canal sealed with mineral trioxide aggregate, glass ionomer cement and composite resin. Resolution of apical periodontitis and the draining sinus, continued root maturation and apical closure occurred over an 18-month period. The tooth became responsive to pulp sensibility testing. It is important that dentists recognize the potential of regenerative endodontics in the treatment of necrotic, immature teeth. Initial management should involve irrigation with sodium hypochlorite only. Intra-canal medicaments, such as calcium hydroxide, are contraindicated as they inhibit further root growth. This report uses a variation of the tri-antibiotic paste currently recommended for regenerative procedures that avoided the discolouration of the crown associated with current protocols. Regenerative endodontics with continued root growth may reduce the risk of fracture and premature tooth loss associated with traditional 'apexification' procedures where the root remains thin and weak. © 2010 Australian Dental Association.

A regenerative elastocaloric heat pump

DEFF Research Database (Denmark)

Engelbrecht, Kurt; Eriksen, Dan; Dallolio, Stefano

2016-01-01

A large fraction of global energy use is for refrigeration and air-conditioning, which could be decarbonized if efficient renewable energy technologies could be found. Vapour-compression technology remains the most widely used system to move heat up the temperature scale after more than 100 years...... a regenerative elastocaloric heat pump that exhibits a temperature span of 15.3 K on the water side with a corresponding specific heating power up to 800 W kg−1 and maximum COP (coefficient-of-performance) values of up to 7. The efficiency and specific heating power of this device exceeds those of other devices...... based on caloric effects. These results open up the possibility of using the elastocaloric effect in various cooling and heat-pumping applications....

Modeling of a Large-Scale High Temperature Regenerative Sulfur Removal Process

DEFF Research Database (Denmark)

Konttinen, Jukka T.; Johnsson, Jan Erik

1999-01-01

model that does not account for bed hydrodynamics. The pilot-scale test run results, obtained in the test runs of the sulfur removal process with real coal gasifier gas, have been used for parameter estimation. The validity of the reactor model for commercial-scale design applications is discussed.......Regenerable mixed metal oxide sorbents are prime candidates for the removal of hydrogen sulfide from hot gasifier gas in the simplified integrated gasification combined cycle (IGCC) process. As part of the regenerative sulfur removal process development, reactor models are needed for scale......-up. Steady-state kinetic reactor models are needed for reactor sizing, and dynamic models can be used for process control design and operator training. The regenerative sulfur removal process to be studied in this paper consists of two side-by-side fluidized bed reactors operating at temperatures of 400...

Placenta and Placental Derivatives in Regenerative Therapies: Experimental Studies, History, and Prospects.

Science.gov (United States)

Pogozhykh, Olena; Prokopyuk, Volodymyr; Figueiredo, Constança; Pogozhykh, Denys

2018-01-01

Placental structures, capable to persist in a genetically foreign organism, are a natural model of allogeneic engraftment carrying a number of distinctive properties. In this review, the main features of the placenta and its derivatives such as structure, cellular composition, immunological and endocrine aspects, and the ability to invasion and deportation are discussed. These features are considered from a perspective that determines the placental material as a unique source for regenerative cell therapies and a lesson for immunological tolerance. A historical overview of clinical applications of placental extracts, cells, and tissue components is described. Empirically accumulated data are summarized and compared with modern research. Furthermore, we define scopes and outlooks of application of placental cells and tissues in the rapidly progressing field of regenerative medicine.

Effect of energy-regenerative braking on electric vehicle battery thermal management and control method based on simulation investigation

International Nuclear Information System (INIS)

Huang, Jingying; Qin, Datong; Peng, Zhiyuan

2015-01-01

Highlights: • A two-degree-of-freedom lumped thermal model is developed for battery. • The battery thermal model is integrated with vehicle driving model. • Real-time battery thermal responses is obtained. • Active control of current by regenerative braking ratio adjustment is proposed. • More energy is recovered with smaller battery temperature rise. - Abstract: Battery thermal management is important for the safety and reliability of electric vehicle. Based on the parameters obtained from battery hybrid pulse power characterization test, a two-degree-of-freedom lumped thermal model is established. The battery model is then integrated with vehicle driving model to simulate real-time battery thermal responses. An active control method is proposed to reduce heat generation due to regenerative braking. The proposed control method not only subjects to the braking safety regulation, but also adjusts the regenerative braking ratio through a fuzzy controller. By comparing with other regenerative braking scenarios, the effectiveness of the proposed strategy has been validated. According to the results, the proposed control strategy suppresses battery temperature rise by modifying the charge current due to regenerative braking. The overlarge components of current are filtered out whereas the small ones are magnified. Therefore, with smaller battery temperature rise, more energy is recovered. Compared to the traditional passive heat dissipating, the proposed active methodology is feasible and provides a novel solution for electric vehicle battery thermal management.

ADRES : autonomous decentralized regenerative energy systems

Energy Technology Data Exchange (ETDEWEB)

Brauner, G.; Einfalt, A.; Leitinger, C.; Tiefgraber, D. [Vienna Univ. of Technology (Austria)

2007-07-01

The autonomous decentralized regenerative energy systems (ADRES) research project demonstrates that decentralized network independent microgrids are the target power systems of the future. This paper presented a typical structure of a microgrid, demonstrating that all types of generation available can be integrated, from wind and small hydro to photovoltaic, fuel cell, biomass or biogas operated stirling motors and micro turbines. In grid connected operation the balancing energy and reactive power for voltage control will come from the public grid. If there is no interconnection to a superior grid, it will form an autonomous micro grid. In order to reduce peak power demand and base energy, autonomous microgrid technology requires highly efficient appliances. Otherwise large collector design, high storage and balancing generation capacities would be necessary, which would increase costs. End-use energy efficiency was discussed with reference to demand side management (DSM) strategies that match energy demand with actual supply in order to minimize the storage size needed. This paper also discussed network controls that comprise active and reactive power. Decentralized robust algorithms were investigated with reference to black-start ability and congestion management features. It was concluded that the trend to develop small decentralized grids in parallel to existing large systems will improve security of supply and reduce greenhouse gas emissions. Decentralized grids will also increase energy efficiency because regenerative energy will be used where it is collected in the form of electricity and heat, thus avoiding transport and the extension of transmission lines. Decentralized energy technology is now becoming more economic by efficient and economic mass production of components. Although decentralized energy technology requires energy automation, computer intelligence is becoming increasingly cost efficient. 2 refs., 4 figs.

Biodegradable Polyphosphazene-Based Blends for Regenerative Engineering.

Science.gov (United States)

Ogueri, Kenneth S; Escobar Ivirico, Jorge L; Nair, Lakshmi S; Allcock, Harry R; Laurencin, Cato T

2017-03-01

The occurrence of musculoskeletal tissue injury or disease and the subsequent functional impairment is at an alarming rate. It continues to be one of the most challenging problems in the human health care. Regenerative engineering offers a promising transdisciplinary strategy for tissues regeneration based on the convergence of tissue engineering, advanced materials science, stem cell science, developmental biology and clinical translation. Biomaterials are emerging as extracellular-mimicking matrices designed to provide instructive cues to control cell behavior and ultimately, be applied as therapies to regenerate damaged tissues. Biodegradable polymers constitute an attractive class of biomaterials for the development of scaffolds due to their flexibility in chemistry and the ability to be excreted or resorbed by the body. Herein, the focus will be on biodegradable polyphosphazene-based blend systems. The synthetic flexibility of polyphosphazene, combined with the unique inorganic backbone, has provided a springboard for more research and subsequent development of numerous novel materials that are capable of forming miscible blends with poly (lactide-co-glycolide) (PLAGA). Laurencin and co-workers has demonstrated the exploitation of the synthetic flexibility of Polyphosphazene that will allow the design of novel polymers, which can form miscible blends with PLAGA for biomedical applications. These novel blends, due to their well-tuned biodegradability, and mechanical and biological properties coupled with the buffering capacity of the degradation products, constitute ideal materials for regeneration of various musculoskeletal tissues. Regenerative engineering aims to regenerate complex tissues to address the clinical challenge of organ damage. Tissue engineering has largely focused on the restoration and repair of individual tissues and organs, but over the past 25 years, scientific, engineering, and medical advances have led to the introduction of this new

Biodegradable Polyphosphazene-Based Blends for Regenerative Engineering

Science.gov (United States)

Ogueri, Kenneth S.; Escobar Ivirico, Jorge L.; Nair, Lakshmi S.; Allcock, Harry R.; Laurencin, Cato T.

2017-01-01

The occurrence of musculoskeletal tissue injury or disease and the subsequent functional impairment is at an alarming rate. It continues to be one of the most challenging problems in the human health care. Regenerative engineering offers a promising transdisciplinary strategy for tissues regeneration based on the convergence of tissue engineering, advanced materials science, stem cell science, developmental biology and clinical translation. Biomaterials are emerging as extracellular-mimicking matrices designed to provide instructive cues to control cell behavior and ultimately, be applied as therapies to regenerate damaged tissues. Biodegradable polymers constitute an attractive class of biomaterials for the development of scaffolds due to their flexibility in chemistry and the ability to be excreted or resorbed by the body. Herein, the focus will be on biodegradable polyphosphazene-based blend systems. The synthetic flexibility of polyphosphazene, combined with the unique inorganic backbone, has provided a springboard for more research and subsequent development of numerous novel materials that are capable of forming miscible blends with poly (lactide-co-glycolide) (PLAGA). Laurencin and co-workers has demonstrated the exploitation of the synthetic flexibility of Polyphosphazene that will allow the design of novel polymers, which can form miscible blends with PLAGA for biomedical applications. These novel blends, due to their well-tuned biodegradability, and mechanical and biological properties coupled with the buffering capacity of the degradation products, constitute ideal materials for regeneration of various musculoskeletal tissues. Lay Summary Regenerative engineering aims to regenerate complex tissues to address the clinical challenge of organ damage. Tissue engineering has largely focused on the restoration and repair of individual tissues and organs, but over the past 25 years, scientific, engineering, and medical advances have led to the introduction of

Regenerative memory in time-delayed neuromorphic photonic resonators

OpenAIRE

Romeira, B.; Avó, R.; Figueiredo, José M. L.; Barland, S.; Javaloyes, J.

2016-01-01

We investigate a photonic regenerative memory based upon a neuromorphic oscillator with a delayed self-feedback (autaptic) connection. We disclose the existence of a unique temporal response characteristic of localized structures enabling an ideal support for bits in an optical buffer memory for storage and reshaping of data information. We link our experimental implementation, based upon a nanoscale nonlinear resonant tunneling diode driving a laser, to the paradigm of neuronal activity, the...

Regenerative burner systems for batch furnaces in the steel industry; Regenerativbrenner fuer Doppel-P-Strahlheizrohre in einer Feuerverzinkungslinie

Energy Technology Data Exchange (ETDEWEB)

Georgiew, A. [Salzgitter Flachstahl GmbH, Salzgitter (Germany); Wuenning, J.G.; Bonnet, U. [WS Waermeprozesstechnik GmbH, Renningen (Germany)

2007-09-15

This article will describe the application of a new self regenerative burner in a continuous galvanizing line. After a brief introduction of the process line, the self regenerative burner will be described. Very high air preheat temperatures enable considerable energy savings and flameless oxidation suppresses the formation of NO{sub x}. (orig.)

Regenerative burner systems for batch furnaces in the steel industry; Regenerativbrenner fuer Doppel-P-Strahlheizrohre in einer Feuerverzinkungslinie

Energy Technology Data Exchange (ETDEWEB)

Georgiew, Alexander [Salzgitter Flachstahl GmbH, Salzgitter (Germany); Wuenning, Joachim G.; Bonnet, Uwe [WS Waermeprozesstechnik GmbH, Renningen (Germany)

2009-07-01

This article will describe the application of a new self regenerative burner in a continuous galvanizing line. After a brief introduction of the process line, the self regenerative burner will be described. Very high air preheat temperatures enable considerable energy savings and flameless oxidation suppresses the formation of NO{sub X}. (orig.)

Understanding positional cues in salamander limb regeneration: implications for optimizing cell-based regenerative therapies

Directory of Open Access Journals (Sweden)

Catherine D. McCusker

2014-06-01

Full Text Available Regenerative medicine has reached the point where we are performing clinical trials with stem-cell-derived cell populations in an effort to treat numerous human pathologies. However, many of these efforts have been challenged by the inability of the engrafted populations to properly integrate into the host environment to make a functional biological unit. It is apparent that we must understand the basic biology of tissue integration in order to apply these principles to the development of regenerative therapies in humans. Studying tissue integration in model organisms, where the process of integration between the newly regenerated tissues and the ‘old’ existing structures can be observed and manipulated, can provide valuable insights. Embryonic and adult cells have a memory of their original position, and this positional information can modify surrounding tissues and drive the formation of new structures. In this Review, we discuss the positional interactions that control the ability of grafted cells to integrate into existing tissues during the process of salamander limb regeneration, and discuss how these insights could explain the integration defects observed in current cell-based regenerative therapies. Additionally, we describe potential molecular tools that can be used to manipulate the positional information in grafted cell populations, and to promote the communication of positional cues in the host environment to facilitate the integration of engrafted cells. Lastly, we explain how studying positional information in current cell-based therapies and in regenerating limbs could provide key insights to improve the integration of cell-based regenerative therapies in the future.

3D Biomaterial Microarrays for Regenerative Medicine

DEFF Research Database (Denmark)

Gaharwar, Akhilesh K.; Arpanaei, Ayyoob; Andresen, Thomas Lars

2015-01-01

Three dimensional (3D) biomaterial microarrays hold enormous promise for regenerative medicine because of their ability to accelerate the design and fabrication of biomimetic materials. Such tissue-like biomaterials can provide an appropriate microenvironment for stimulating and controlling stem...... for tissue engineering and drug screening applications....... cell differentiation into tissue-specifi c lineages. The use of 3D biomaterial microarrays can, if optimized correctly, result in a more than 1000-fold reduction in biomaterials and cells consumption when engineering optimal materials combinations, which makes these miniaturized systems very attractive...

Preliminary thermodynamic study of regenerative Otto based cycles with zero NOx emissions operating with adiabatic and polytropic expansion

International Nuclear Information System (INIS)

Garcia, Ramon Ferreiro; Carril, Jose Carbia; Romero Gomez, Javier; Romero Gomez, Manuel

2016-01-01

Highlights: • Efficient polytropic expansion based Otto cycle. • Thermal efficiency is due to the inherent regeneration. • Low temperature combustion with zero NOx emissions. - Abstract: The aim of the paper is to demonstrate that a regenerative Otto cycle with adiabatic or polytropic expansion can achieve improved performance over traditional Otto engines, even exceeding the Carnot factor. Thus, the work deals with a novel regenerative Otto based internal combustion engine which differs from the conventional Otto thermal cycles in that the process of heat conversion into mechanical work is performed obeying a polytropic path function instead of the conventional adiabatic expansion without regeneration. Design characteristics concern the fact that combustion at constant volume is carried out undergoing large air excess so that the top combustion temperature is significantly lower than in conventional Otto cycles and consequently NOx emissions are neglected. Furthermore, during the polytropic expansion based path function, heat is absorbed by being submitted to a controlled heat flow rate, to achieve the desired polytropic expansion. The analysis of the regenerative Otto based on polytropic expansion is presented and results are compared with a regenerative Otto based on the adiabatic expansion and CF. The results show that a relevant advantage of the proposed regenerative Otto with polytropic expansion over the regenerative Otto cycle with adiabatic expansion involves performance enhancement within a wide range of combustion pressures, temperatures and regeneration capacities. Thus, thermal efficiency and specific work as function of the top combustion pressure ranges are of 71.95–58.43% and 143.5–173.6 kJ/kg respectively, when combustion pressures vary between 105 kPa and 200 kPa and CF is 60.8% (lower than the thermal efficiency). The successful results involving a compact engine structure, technically and economically viable, promises a new generation

Neural growth into a microchannel network: towards a regenerative neural interface

NARCIS (Netherlands)

Wieringa, P.A.; Wiertz, Remy; le Feber, Jakob; Rutten, Wim

2009-01-01

We propose and validated a design for a highly selective 'endcap' regenerative neural interface towards a neuroprosthesis. In vitro studies using rat cortical neurons determine if a branching microchannel structure can counter fasciculated growth and cause neurites to separte from one another,

Dual Affinity Heparin-Based Hydrogels Achieve Pro-Regenerative Immunomodulation and Microvascular Remodeling.

Science.gov (United States)

Ogle, Molly E; Krieger, Jack R; Tellier, Liane E; McFaline-Figueroa, Jennifer; Temenoff, Johnna S; Botchwey, Edward A

2018-04-09

The immune response to biomaterial implants critically regulates functional outcomes such as vascularization, transplant integration/survival, and fibrosis. To create "immunologically smart" materials, the host-material response may be engineered to optimize the recruitment of pro-regenerative leukocyte subsets which mature into corresponding wound-healing macrophages. We have recently identified a unique feature of pro-regenerative Ly6C low monocytes that is a higher expression of both the bioactive lipid receptor sphingosine-1-phosphate receptor 3 (S1PR3) and the stromal derived factor-1α (SDF-1α) receptor CXCR4. Therefore, we designed a bifunctional hydrogel to harnesses a mechanistic synergy between these signaling axes to enhance the recruitment of endogenous pro-regenerative monocytes. To overcome the challenge of codelivering two physiochemically distinct molecules-a large hydrophilic protein and hydrophobic small molecule-we engineered a dual affinity hydrogel that exploits the growth factor affinity of a heparin derivative (Hep -N ) and lipid chaperone activity of albumin. The sphingosine analog FTY720 and SDF-1α are successfully loaded and coreleased from the Hep -N -functionalized PEG-DA hydrogels while maintaining bioactivity. Placement of these hydrogels into a murine partial thickness skin wound demonstrates that corelease of FTY720 and SDF-1α yields superior recruitment of myeloid cells to the implant interface compared to either factor alone. Although in vivo delivery of FTY720 or SDF-1α individually promotes the enhanced recruitment of Ly-6C low anti-inflammatory monocytes, codelivery enhances the early accumulation and persistence of the differentiated wound healing CD206 + macrophages in the tissue surrounding the gel. Co-delivery similarly promoted the synergistic expansion of vasculature adjacent to the implant, a key step in tissue healing. Taken together, these findings suggest that the combination of chemotactic molecules may provide

Regeneration and Repair in Endodontics—A Special Issue of the Regenerative Endodontics—A New Era in Clinical Endodontics

Science.gov (United States)

Saoud, Tarek Mohamed A.; Ricucci, Domenico; Lin, Louis M.; Gaengler, Peter

2016-01-01

Caries is the most common cause of pulp-periapical disease. When the pulp tissue involved in caries becomes irreversibly inflamed and progresses to necrosis, the treatment option is root canal therapy because the infected or non-infected necrotic pulp tissue in the root canal system is not accessible to the host's innate and adaptive immune defense mechanisms and antimicrobial agents. Therefore, the infected or non-infected necrotic pulp tissue must be removed from the canal space by pulpectomy. As our knowledge in pulp biology advances, the concept of treatment of pulpal and periapical disease also changes. Endodontists have been looking for biologically based treatment procedures, which could promote regeneration or repair of the dentin-pulp complex destroyed by infection or trauma for several decades. After a long, extensive search in in vitro laboratory and in vivo preclinical animal experiments, the dental stem cells capable of regenerating the dentin-pulp complex were discovered. Consequently, the biological concept of ‘regenerative endodontics’ emerged and has highlighted the paradigm shift in the treatment of immature permanent teeth with necrotic pulps in clinical endodontics. Regenerative endodontics is defined as biologically based procedures designed to physiologically replace damaged tooth structures, including dentin and root structures, as well as the pulp-dentin complex. According to the American Association of Endodontists’ Clinical Considerations for a Regenerative Procedure, the primary goal of the regenerative procedure is the elimination of clinical symptoms and the resolution of apical periodontitis. Thickening of canal walls and continued root maturation is the secondary goal. Therefore, the primary goal of regenerative endodontics and traditional non-surgical root canal therapy is the same. The difference between non-surgical root canal therapy and regenerative endodontic therapy is that the disinfected root canals in the former

Regeneration and Repair in Endodontics-A Special Issue of the Regenerative Endodontics-A New Era in Clinical Endodontics.

Science.gov (United States)

Saoud, Tarek Mohamed A; Ricucci, Domenico; Lin, Louis M; Gaengler, Peter

2016-02-27

Caries is the most common cause of pulp-periapical disease. When the pulp tissue involved in caries becomes irreversibly inflamed and progresses to necrosis, the treatment option is root canal therapy because the infected or non-infected necrotic pulp tissue in the root canal system is not accessible to the host's innate and adaptive immune defense mechanisms and antimicrobial agents. Therefore, the infected or non-infected necrotic pulp tissue must be removed from the canal space by pulpectomy. As our knowledge in pulp biology advances, the concept of treatment of pulpal and periapical disease also changes. Endodontists have been looking for biologically based treatment procedures, which could promote regeneration or repair of the dentin-pulp complex destroyed by infection or trauma for several decades. After a long, extensive search in in vitro laboratory and in vivo preclinical animal experiments, the dental stem cells capable of regenerating the dentin-pulp complex were discovered. Consequently, the biological concept of 'regenerative endodontics' emerged and has highlighted the paradigm shift in the treatment of immature permanent teeth with necrotic pulps in clinical endodontics. Regenerative endodontics is defined as biologically based procedures designed to physiologically replace damaged tooth structures, including dentin and root structures, as well as the pulp-dentin complex. According to the American Association of Endodontists' Clinical Considerations for a Regenerative Procedure, the primary goal of the regenerative procedure is the elimination of clinical symptoms and the resolution of apical periodontitis. Thickening of canal walls and continued root maturation is the secondary goal. Therefore, the primary goal of regenerative endodontics and traditional non-surgical root canal therapy is the same. The difference between non-surgical root canal therapy and regenerative endodontic therapy is that the disinfected root canals in the former therapy are

Regeneration and Repair in Endodontics—A Special Issue of the Regenerative Endodontics—A New Era in Clinical Endodontics

Directory of Open Access Journals (Sweden)

Tarek Mohamed A. Saoud

2016-02-01

Full Text Available Caries is the most common cause of pulp-periapical disease. When the pulp tissue involved in caries becomes irreversibly inflamed and progresses to necrosis, the treatment option is root canal therapy because the infected or non-infected necrotic pulp tissue in the root canal system is not accessible to the host's innate and adaptive immune defense mechanisms and antimicrobial agents. Therefore, the infected or non-infected necrotic pulp tissue must be removed from the canal space by pulpectomy. As our knowledge in pulp biology advances, the concept of treatment of pulpal and periapical disease also changes. Endodontists have been looking for biologically based treatment procedures, which could promote regeneration or repair of the dentin-pulp complex destroyed by infection or trauma for several decades. After a long, extensive search in in vitro laboratory and in vivo preclinical animal experiments, the dental stem cells capable of regenerating the dentin-pulp complex were discovered. Consequently, the biological concept of ‘regenerative endodontics’ emerged and has highlighted the paradigm shift in the treatment of immature permanent teeth with necrotic pulps in clinical endodontics. Regenerative endodontics is defined as biologically based procedures designed to physiologically replace damaged tooth structures, including dentin and root structures, as well as the pulp-dentin complex. According to the American Association of Endodontists’ Clinical Considerations for a Regenerative Procedure, the primary goal of the regenerative procedure is the elimination of clinical symptoms and the resolution of apical periodontitis. Thickening of canal walls and continued root maturation is the secondary goal. Therefore, the primary goal of regenerative endodontics and traditional non-surgical root canal therapy is the same. The difference between non-surgical root canal therapy and regenerative endodontic therapy is that the disinfected root canals

Analysis of downshift’s improvement to energy efficiency of an electric vehicle during regenerative braking

International Nuclear Information System (INIS)

Li, Liang; Li, Xujian; Wang, Xiangyu; Song, Jian; He, Kai; Li, Chenfeng

2016-01-01

Highlights: • Downshift is effective in improving the energy efficiency of electric vehicles. • Energy improvement of downshift varies with vehicle speed and brake strength. • The designed nonlinear sliding mode observer is accurate in estimating bake torque. • The proposed resembling PWM method is practical to regulate hydraulic pressure. • The effect of downshift on braking safety and comfort can be restrained by control. - Abstract: Downshift during regenerative braking helps to improve the energy efficiency of electric vehicles. Two main problems are involved in the downshift process. One is the determination of optimal downshift point, and the other is the cooperative control of regenerative braking and hydraulic braking. In order to achieve a systemic solution to these problems, a hierarchical control strategy is brought forward for an electric vehicle with a two-speed automated mechanical transmission. For the upper controller, an off-line calculation and on-line look-up table method is adopted to obtain the optimal downshift point, and a series regenerative braking distribution strategy is designed. For the medium controller, a nonlinear sliding mode observer is designed to obtain the actual hydraulic brake torque. For the lower controller, cooperative control of regenerative braking and hydraulic braking is given to ensure brake safety during downshift process, and a resembling pulse width modulation method is proposed to regulated the hydraulic brake torque. Simulation results and hardware-in-loop test show that the proposed algorithm is effective in improving the energy efficiency of electric vehicles.

Caenorhabditis elegans in regenerative medicine: a simple model for a complex discipline.

Science.gov (United States)

Aitlhadj, Layla; Stürzenbaum, Stephen R

2014-06-01

Stem cell research is a major focus of regenerative medicine, which amalgamates diverse disciplines ranging from developmental cell biology to chemical and genetic therapy. Although embryonic stem cells have provided the foundation of stem cell therapy, they offer an in vitro study system that might not provide the best insight into mechanisms and behaviour of cells within living organisms. Caenorhabditis elegans is a well defined model organism with highly conserved cell development and signalling processes that specify cell fate. Its genetic amenability coupled with its chemical screening applicability make the nematode well suited as an in vivo system in which regenerative therapy and stem cell processes can be explored. Here, we describe some of the major advances in stem cell research from the worm's perspective. Copyright © 2014 Elsevier Ltd. All rights reserved.

Placenta and Placental Derivatives in Regenerative Therapies: Experimental Studies, History, and Prospects

Directory of Open Access Journals (Sweden)

Olena Pogozhykh

2018-01-01

Full Text Available Placental structures, capable to persist in a genetically foreign organism, are a natural model of allogeneic engraftment carrying a number of distinctive properties. In this review, the main features of the placenta and its derivatives such as structure, cellular composition, immunological and endocrine aspects, and the ability to invasion and deportation are discussed. These features are considered from a perspective that determines the placental material as a unique source for regenerative cell therapies and a lesson for immunological tolerance. A historical overview of clinical applications of placental extracts, cells, and tissue components is described. Empirically accumulated data are summarized and compared with modern research. Furthermore, we define scopes and outlooks of application of placental cells and tissues in the rapidly progressing field of regenerative medicine.

Epigenetic modulation of dental pulp stem cells: implications for regenerative endodontics.

Science.gov (United States)

Duncan, H F; Smith, A J; Fleming, G J P; Cooper, P R

2016-05-01

Dental pulp stem cells (DPSCs) offer significant potential for use in regenerative endodontics, and therefore, identifying cellular regulators that control stem cell fate is critical to devising novel treatment strategies. Stem cell lineage commitment and differentiation are regulated by an intricate range of host and environmental factors of which epigenetic influence is considered vital. Epigenetic modification of DNA and DNA-associated histone proteins has been demonstrated to control cell phenotype and regulate the renewal and pluripotency of stem cell populations. The activities of the nuclear enzymes, histone deacetylases, are increasingly being recognized as potential targets for pharmacologically inducing stem cell differentiation and dedifferentiation. Depending on cell maturity and niche in vitro, low concentration histone deacetylase inhibitor (HDACi) application can promote dedifferentiation of several post-natal and mouse embryonic stem cell populations and conversely increase differentiation and accelerate mineralization in DPSC populations, whilst animal studies have shown an HDACi-induced increase in stem cell marker expression during organ regeneration. Notably, both HDAC and DNA methyltransferase inhibitors have also been demonstrated to dramatically increase the reprogramming of somatic cells to induced pluripotent stem cells (iPSCs) for use in regenerative therapeutic procedures. As the regulation of cell fate will likely remain the subject of intense future research activity, this review aims to describe the current knowledge relating to stem cell epigenetic modification, focusing on the role of HDACi on alteration of DPSC phenotype, whilst presenting the potential for therapeutic application as part of regenerative endodontic regimens. © 2015 International Endodontic Journal. Published by John Wiley & Sons Ltd.

Surgical Regenerative Treatments for Peri-Implantitis: Meta-analysis of Recent Findings in a Systematic Literature Review

Directory of Open Access Journals (Sweden)

Povilas Daugela

2016-09-01

Full Text Available Objectives: The purpose of the present study was to systematically review the literature on the surgical regenerative treatment of the peri-implantitis and to determine an effective therapeutic predictable option for their clinical management. Material and Methods: The study searched MEDLINE and EMBASE databases from 2006 to 2016. Clinical human studies that had reported changes in probing depth (PD and/or bleeding on probing (BOP and/or radiologic marginal bone level (RBL changes after peri-implantitis surgical treatment at 12-month follow-up or longer were included accordingly to PRISMA guidelines. Results: The initial search obtained 883 citations. After screening and determination of eligibility, 18 articles were included in the review. The meta-analysis of selected studies revealed that the weighted mean RBL fill was 1.97 mm (95% confidence interval [CI] = 1.58 to 2.35 mm, PD reduction was 2.78 mm (95% CI = 2.31 to 3.25 mm, and BOP reduced by 52.5% (95% CI = 41.6 to 63.1%. Defect fill in studies using and not using barrier membranes for graft coverage was 1.86 mm (95% CI = 1.36 to 2.36 mm and 2.12 mm (95% CI = 1.46 to 2.78 mm correspondingly. High heterogeneity among the studies regarding defects morphology, surgical protocols, and selection of biomaterials were found. Conclusions: All included studies underlined an improvement of clinical conditions after the surgical regenerative treatment of peri-implantitis, however, there is a lack of scientific evidence in the literature regarding the superiority of the regenerative versus non-regenerative surgical treatment. The presence of a barrier membrane or submergence in the regenerative procedure does not seem to be fundamental in order to obtain clinical success of the surgery.

Translating cell-based regenerative medicines from research to successful products: challenges and solutions.

Science.gov (United States)

Bayon, Yves; Vertès, Alain A; Ronfard, Vincent; Egloff, Matthieu; Snykers, Sarah; Salinas, Gabriella Franco; Thomas, Robert; Girling, Alan; Lilford, Richard; Clermont, Gaelle; Kemp, Paul

2014-08-01

The Tissue Engineering & Regenerative Medicine International Society-Europe (TERMIS-EU) Industry Committee as well as its TERMIS-Americas (AM) counterpart intend to address the specific challenges and needs facing the industry in translating academic research into commercial products. Over the last 3 years, the TERMIS-EU Industry Committee has worked with commercial bodies to deliver programs that encourage academics to liaise with industry in proactive collaborations. The TERMIS-EU 2013 Industry Symposium aimed to build on this commercial agenda by focusing on two topics: Operations Management (How to move a process into the good manufacturing practice [GMP] environment) and Clinical Translation (Moving a GMP process into robust trials). These topics were introduced by providing the synergistic business perspective of partnering between the multiple regenerative medicine stakeholders, throughout the life cycle of product development. Seven industry leaders were invited to share their experience, expertise, and strategies. Due to the complex nature of regenerative medicine products, partnering for their successful commercial development seems inevitable to overcome all obstacles by sharing experiences and expertise of all stakeholders. When ideally implemented, the "innovation quotient" of a virtual team resulting from the combination of internal and external project teams can be maximized through maximizing the three main dimensions: core competences, technology portfolio, and alliance management.

Thermodynamic analysis of an organic rankine cycle using a tubular solar cavity receiver

International Nuclear Information System (INIS)

Loni, R.; Kasaeian, A.B.; Mahian, O.; Sahin, A.Z.

2016-01-01

Highlights: • A non-regenerative Organic Rankine Cycle has been analyzed. • R113, R601, R11, R141b, Ethanol and Methanol were used as the working fluid. • A parabolic dish concentrator with a square prismatic cavity receiver was used. • Thermal efficiency, second law efficiency, and net power output were analyzed. - Abstract: In this study, a non-regenerative Organic Rankine Cycle (ORC) has been thermodynamically analyzed under superheated conditions, constant evaporator pressure of 2.5 MPa, and condenser temperature of 300 K. R113, R601, R11, R141b, Ethanol and Methanol were employed as the working fluid. A parabolic dish concentrator with a square prismatic tubular cavity receiver was used as the heat source of the ORC system. The effects of the tube diameter, the cavity depth, and the solar irradiation on the thermodynamic performance of the selected working fluid were investigated. Some thermodynamic parameters were analyzed in this study. These thermodynamic parameters included the thermal efficiency, second law efficiency, total irreversibility, availability ratio, mass flow rate, and net power output. The results showed that, among the selected working fluids, methanol had the highest thermal efficiency, net power output, second law efficiency, and availability ratio in the range of turbine inlet temperature (TIT) considered. On the other hand, methanol had the smallest total irreversibility in the same range of TIT. The results showed also that mass flow rate and consequently the net power output increased for higher solar irradiation, smaller tube diameter, and for the case of cubical cavity receiver (i.e. cavity depth h equal to the receiver aperture side length a).

Microfabricated modular scale-down device for regenerative medicine process development.

Directory of Open Access Journals (Sweden)

Marcel Reichen

Full Text Available The capacity of milli and micro litre bioreactors to accelerate process development has been successfully demonstrated in traditional biotechnology. However, for regenerative medicine present smaller scale culture methods cannot cope with the wide range of processing variables that need to be evaluated. Existing microfabricated culture devices, which could test different culture variables with a minimum amount of resources (e.g. expensive culture medium, are typically not designed with process development in mind. We present a novel, autoclavable, and microfabricated scale-down device designed for regenerative medicine process development. The microfabricated device contains a re-sealable culture chamber that facilitates use of standard culture protocols, creating a link with traditional small-scale culture devices for validation and scale-up studies. Further, the modular design can easily accommodate investigation of different culture substrate/extra-cellular matrix combinations. Inactivated mouse embryonic fibroblasts (iMEF and human embryonic stem cell (hESC colonies were successfully seeded on gelatine-coated tissue culture polystyrene (TC-PS using standard static seeding protocols. The microfluidic chip included in the device offers precise and accurate control over the culture medium flow rate and resulting shear stresses in the device. Cells were cultured for two days with media perfused at 300 µl.h(-1 resulting in a modelled shear stress of 1.1×10(-4 Pa. Following perfusion, hESC colonies stained positively for different pluripotency markers and retained an undifferentiated morphology. An image processing algorithm was developed which permits quantification of co-cultured colony-forming cells from phase contrast microscope images. hESC colony sizes were quantified against the background of the feeder cells (iMEF in less than 45 seconds for high-resolution images, which will permit real-time monitoring of culture progress in future

STATISTIC, PROBABILISTIC, CORRELATION AND SPECTRAL ANALYSES OF REGENERATIVE BRAKING CURRENT OF DC ELECTRIC ROLLING STOCK

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A. V. Nikitenko

2014-04-01

Full Text Available Purpose. Defining and analysis of the probabilistic and spectral characteristics of random current in regenerative braking mode of DC electric rolling stock are observed in this paper. Methodology. The elements and methods of the probability theory (particularly the theory of stationary and non-stationary processes and methods of the sampling theory are used for processing of the regenerated current data arrays by PC. Findings. The regenerated current records are obtained from the locomotives and trains in Ukraine railways and trams in Poland. It was established that the current has uninterrupted and the jumping variations in time (especially in trams. For the random current in the regenerative braking mode the functions of mathematical expectation, dispersion and standard deviation are calculated. Histograms, probabilistic characteristics and correlation functions are calculated and plotted down for this current too. It was established that the current of the regenerative braking mode can be considered like the stationary and non-ergodic process. The spectral analysis of these records and “tail part” of the correlation function found weak periodical (or low-frequency components which are known like an interharmonic. Originality. Firstly, the theory of non-stationary random processes was adapted for the analysis of the recuperated current which has uninterrupted and the jumping variations in time. Secondly, the presence of interharmonics in the stochastic process of regenerated current was defined for the first time. And finally, the patterns of temporal changes of the correlation current function are defined too. This allows to reasonably apply the correlation functions method in the identification of the electric traction system devices. Practical value. The results of probabilistic and statistic analysis of the recuperated current allow to estimate the quality of recovered energy and energy quality indices of electric rolling stock in the

Heat cascading regenerative sorption heat pump

Science.gov (United States)

Jones, Jack A. (Inventor)

1995-01-01

A simple heat cascading regenerative sorption heat pump process with rejected or waste heat from a higher temperature chemisorption circuit (HTCC) powering a lower temperature physisorption circuit (LTPC) which provides a 30% total improvement over simple regenerative physisorption compression heat pumps when ammonia is both the chemisorbate and physisorbate, and a total improvement of 50% or more for LTPC having two pressure stages. The HTCC contains ammonia and a chemisorbent therefor contained in a plurality of canisters, a condenser-evaporator-radiator system, and a heater, operatively connected together. The LTPC contains ammonia and a physisorbent therefor contained in a plurality of compressors, a condenser-evaporator-radiator system, operatively connected together. A closed heat transfer circuit (CHTC) is provided which contains a flowing heat transfer liquid (FHTL) in thermal communication with each canister and each compressor for cascading heat from the HTCC to the LTPC. Heat is regenerated within the LTPC by transferring heat from one compressor to another. In one embodiment the regeneration is performed by another CHTC containing another FHTL in thermal communication with each compressor. In another embodiment the HTCC powers a lower temperature ammonia water absorption circuit (LTAWAC) which contains a generator-absorber system containing the absorbent, and a condenser-evaporator-radiator system, operatively connected together. The absorbent is water or an absorbent aqueous solution. A CHTC is provided which contains a FHTL in thermal communication with the generator for cascading heat from the HTCC to the LTAWAC. Heat is regenerated within the LTAWAC by transferring heat from the generator to the absorber. The chemical composition of the chemisorbent is different than the chemical composition of the physisorbent, and the absorbent. The chemical composition of the FHTL is different than the chemisorbent, the physisorbent, the absorbent, and ammonia.

Stem Cell and Regenerative Medicine Global Conference (SCRGC) 2016 (August 23-24, 2016 - Gyeonggi-do, Korea).

Science.gov (United States)

Vertès, A

2016-10-01

In its third edition, the Stem Cell and Regenerative Medicine Global Conference (SCRGC) organized by the Global Stem Cell & Regenerative Medicine Acceleration Center (GSRAC) was focused on breaking barriers to accelerate the pace of innovation and development of the regenerative medicine industry. GSRAC is both a think tank and a global network of key opinion leaders from the public and the private sectors. GSRAC was commissioned in 2011 by the Ministry of Health and Welfare (MOHW) of Korea. GSRAC's primary mission is to enable and accelerate the delivery of innovative technologies to patients who are affected by currently untreatable diseases. This goal is notably achieved by resolving hurdles in the field of regenerative medicine. With a total of 30 speakers and panelists from 8 different countries and more than 400 attendees from an array of institutions including hospitals, clinics, biotechnology companies, pharmaceutical companies, scientists, as well as policy makers, the 2-day SCRGC highlighted critical challenges and paths to resolving them in policy and regulatory, and industrial-scale manufacturing of gene-based and cell-based therapies, comprising plenary lectures and sessions covering strategic policy, regulatory, reimbursement and business development, and business of manufacturing, and production technologies. Several of these presentations are summarized in this report. Copyright 2016 Prous Science, S.A.U. or its licensors. All rights reserved.

Endothelial Jagged-1 Is Necessary for Homeostatic and Regenerative Hematopoiesis

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Michael G. Poulos

2013-09-01

Full Text Available The bone marrow (BM microenvironment is composed of multiple niche cells that, by producing paracrine factors, maintain and regenerate the hematopoietic stem cell (HSC pool (Morrison and Spradling, 2008. We have previously demonstrated that endothelial cells support the proper regeneration of the hematopoietic system following myeloablation (Butler et al., 2010; Hooper et al., 2009; Kobayashi et al., 2010. Here, we demonstrate that expression of the angiocrine factor Jagged-1, supplied by the BM vascular niche, regulates homeostatic and regenerative hematopoiesis through a Notch-dependent mechanism. Conditional deletion of Jagged-1 in endothelial cells (Jag1(ECKO mice results in a profound decrease in hematopoiesis and premature exhaustion of the adult HSC pool, whereas quantification and functional assays demonstrate that loss of Jagged-1 does not perturb vascular or mesenchymal compartments. Taken together, these data demonstrate that the instructive function of endothelial-specific Jagged-1 is required to support the self-renewal and regenerative capacity of HSCs in the adult BM vascular niche.

Clinical concepts for regenerative therapy in intrabony defects.

Science.gov (United States)

Cortellini, Pierpaolo; Tonetti, Maurizio S

2015-06-01

Evidence indicates that periodontal regeneration is an efficacious and predictable procedure for the treatment of isolated and multiple intrabony defects. Meta-analyses from systematic reviews indicate an added benefit, in terms of clinical attachment level gain, when demineralized freeze-dried bone allograft, barrier membranes and active biologic products/compounds are applied in addition to open flap debridement. On the other hand, a consistent amount of variability of the outcomes is evident among different studies and within the experimental population of each study. This variability is explained, at least in part, by different patient and defect characteristics. Patient-related factors include smoking habit, compliance with home oral hygiene and residual inflammation after cause-related therapy. Defect-associated factors include defect depth and radiographic angle, the number of residual bony walls, pocket depth and the degree of hypermobility. In addition, surgical-related variables, such as surgical skill, clinical experience and knowledge, and application of the different regenerative materials, have a significant impact on clinical outcomes. This paper presents a strategy to optimize the clinical outcomes of periodontal regeneration. The surgical design of the flap, the use of different regenerative materials and the application of appropriate passive sutures are discussed in this review along with the scientific foundations. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Understanding Liver Regeneration: From Mechanisms to Regenerative Medicine.

Science.gov (United States)

Gilgenkrantz, Hélène; Collin de l'Hortet, Alexandra

2018-04-16

Liver regeneration is a complex and unique process. When two-thirds of a mouse liver is removed, the remaining liver recovers its initial weight in approximately 10 days. The understanding of the mechanisms responsible for liver regeneration may help patients needing large liver resections or transplantation and may be applied to the field of regenerative medicine. All differentiated hepatocytes are capable of self-renewal, but different subpopulations of hepatocytes seem to have distinct proliferative abilities. In the setting of chronic liver diseases, a ductular reaction ensues in which liver progenitor cells (LPCs) proliferate in the periportal region. Although these LPCs have the capacity to differentiate into hepatocytes and biliary cells in vitro, their ability to participate in liver regeneration is far from clear. Their expansion has even been associated with increased fibrosis and poorer prognosis in chronic liver diseases. Controversies also remain on their origin: lineage studies in experimental mouse models of chronic injury have recently suggested that these LPCs originate from hepatocyte dedifferentiation, whereas in other situations, they seem to come from cholangiocytes. This review summarizes data published in the past 5 years in the liver regeneration field, discusses the mechanisms leading to regeneration disruption in chronic liver disorders, and addresses the potential use of novel approaches for regenerative medicine. Copyright © 2018 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

Ultrasonography, angiography, computed tomography and magnetic resonance in nodular regenerative hyperplasia of the liver

International Nuclear Information System (INIS)

Patriarche, C.; Pelletier, G.; Attali, P.; Ladouch-Badre, A.; Fabre, M.; Roche, A.; Etienne, J.P.

1988-01-01

Ultrasonographic, computed tomographic, and angiographic abnormalities of nodular regenerative hyperplasia have been described in very few cases. We report here the case of a 50-year-old man with round, well-limited hypoechogenic lesions involving the two lobes of the liver, and hypervascular, poorly delineated angiographic lesions. Computed tomography and magnetic resonance of the liver were normal. Histological examination of large liver specimens provided by intraoperative biopsy allowed the diagnosis of nodular regenerative hyperplasia. Such a pseudo-tumoral ultrasonographic and angiographic pattern must be recognized in order to avoid diagnostic and therapeutic mistakes, especially since percutaneous liver biopsy usually fails to diagnose this disease. (author)

CIRM Alpha Stem Cell Clinics: Collaboratively Addressing Regenerative Medicine Challenges.

Science.gov (United States)

Jamieson, Catriona H M; Millan, Maria T; Creasey, Abla A; Lomax, Geoff; Donohoe, Mary E; Walters, Mark C; Abedi, Mehrdad; Bota, Daniela A; Zaia, John A; Adams, John S

2018-06-01

The California Institute for Regenerative Medicine (CIRM) Alpha Stem Cell Clinic (ASCC) Network was launched in 2015 to address a compelling unmet medical need for rigorous, FDA-regulated, stem cell-related clinical trials for patients with challenging, incurable diseases. Here, we describe our multi-center experiences addressing current and future challenges. Copyright © 2018 Elsevier Inc. All rights reserved.

Peroxisome Proliferator-Activated Receptor (PPAR) in Regenerative Medicine: Molecular Mechanism for PPAR in Stem Cells' Adipocyte Differentiation.

Science.gov (United States)

Xie, Qiang; Tian, Taoran; Chen, Zhaozhao; Deng, Shuwen; Sun, Ke; Xie, Jing; Cai, Xiaoxiao

2016-01-01

Regenerative medicine plays an indispensable role in modern medicine and many trials and researches have therefore been developed to fit our medical needs. Tissue engineering has proven that adipose tissue can widely be used and brings advantages to regenerative medicine. Moreover, a trait of adipose stem cells being isolated and grown in vitro is a cornerstone to various applications. Since the adipose tissue has been widely used in regenerative medicine, numerous studies have been conducted to seek methods for gaining more adipocytes. To investigate molecular mechanism for adipocyte differentiation, peroxisome proliferator-activated receptor (PPAR) has been widely studied to find out its functional mechanism, as a key factor for adipocyte differentiation. However, the precise molecular mechanism is still unknown. This review thus summarizes recent progress on the study of molecular mechanism and role of PPAR in adipocyte differentiation.

Aging and Adipose Tissue: Potential Interventions for Diabetes and Regenerative Medicine

Science.gov (United States)

Palmer, Allyson K.; Kirkland, James L.

2016-01-01

Adipose tissue dysfunction occurs with aging and has systemic effects, including peripheral insulin resistance, ectopic lipid deposition, and inflammation. Fundamental aging mechanisms, including cellular senescence and progenitor cell dysfunction, occur in adipose tissue with aging and may serve as potential therapeutic targets in age-related disease. In this review, we examine the role of adipose tissue in healthy individuals and explore how aging leads to adipose tissue dysfunction, redistribution, and changes in gene regulation. Adipose tissue plays a central role in longevity, and interventions restricted to adipose tissue may impact lifespan. Conversely, obesity may represent a state of accelerated aging. We discuss the potential therapeutic potential of targeting basic aging mechanisms, including cellular senescence, in adipose tissue, using type II diabetes and regenerative medicine as examples. We make the case that aging should not be neglected in the study of adipose-derived stem cells for regenerative medicine strategies, as elderly patients make up a large portion of individuals in need of such therapies. PMID:26924669

Modelling of preheated regenerative chain in Cernavoda NPP using MMS calculation code

International Nuclear Information System (INIS)

Bigu, M.; Nita, I.; Prisecaru, I.; Dupleac, D.

2005-01-01

Full text: In this work it was studied operation of preheated regenerative chain from NPP Cernavoda. To obtain this analysis coupled analyses of condensate system, water supply system, and drain cooler system were effected. The analysis boundaries are: Upstream: - Steam condensers - Turbine Bleed Steam Downstream: - Steam Generators. The analysis was made in two steps: 1) Getting of hydraulic characteristic of pipe network from steam condensers to steam generators at nominal regime; this step was obtained with hydraulic package called PIPENET. 2) Real thermal hydraulic analyses were done based on hydraulic characteristic of pipe network and supplementary data required for heat transfer calculation in equipment of preheated regenerative chain. Thermal analyses were done using MMS package and refered to normal operating regimes, namely, nominal operating regime required for calibration of calculating model, shutdown regime, start-up regime from zero power hot to nominal power and to abnormal operating regimes, namely, turbine trip, reactor trip and loss of two condensate pumps. The results were compared with already existing analysis and showed the largest differences at interface areas (i.e. 5%). This led us to idea of extending analysis to all secondary circuits in order to reduce the number of boundary conditions which can generate uncertainty in analysis. In this analysis we obtained an advanced model of preheated regenerative chain of secondary circuit in Cernavoda NPP which could be extended up to cover the whole secondary circuit by including the analysis of steam generators, turbine, and steam condenser. (authors)

Modelling of preheated regenerative chain in Cernavoda NPP using MMS calculation code

International Nuclear Information System (INIS)

Bigu, M.; Nita, I.; Prisecaru, I.; Dupleac, D.

2005-01-01

In this work it was studied operation of preheated regenerative chain from NPP Cernavoda. To obtain this analysis coupled analyses of condensate system, water supply system, and drain cooler system were effected. The analysis boundaries are: Upstream: - Steam condensers - Turbine Bleed Steam Downstream: - Steam Generators. The analysis was made in two steps: 1) Getting of hydraulic characteristic of pipe network from steam condensers to steam generators at nominal regime; this step was obtained with hydraulic package called PIPENET. 2) Real thermal hydraulic analyses were done based on hydraulic characteristic of pipe network and supplementary data required for heat transfer calculation in equipment of preheated regenerative chain. Thermal analyses were done using MMS package and referred to normal operating regimes, namely, nominal operating regime required for calibration of calculating model, shutdown regime, start-up regime from zero power hot to nominal power and to abnormal operating regimes, namely, turbine trip, reactor trip and loss of two condensate pumps. The results were compared with already existing analysis and showed the largest differences at interface areas (i.e. 5%). This led US to idea of extending analysis to all secondary circuits in order to reduce the number of boundary conditions which can generate uncertainty in analysis. In this analysis we obtained an advanced model of preheated regenerative chain of secondary circuit in Cernavoda NPP which could be extended up to cover the whole secondary circuit by including the analysis of steam generators, turbine, and steam condenser. (authors)

Transient switching control strategy from regenerative braking to anti-lock braking with a semi-brake-by-wire system

Science.gov (United States)

Li, Liang; Li, Xujian; Wang, Xiangyu; Liu, Yahui; Song, Jian; Ran, Xu

2016-02-01

Regenerative braking is an important technology in improving fuel economy of an electric vehicle (EV). However, additional motor braking will change the dynamic characteristics of the vehicle, leading to braking instability, especially when the anti-lock braking system (ABS) is triggered. In this paper, a novel semi-brake-by-wire system, without the use of a pedal simulator and fail-safe device, is proposed. In order to compensate for the hysteretic characteristics of the designed brake system while ensure braking reliability and fuel economy when the ABS is triggered, a novel switching compensation control strategy using sliding mode control is brought forward. The proposed strategy converts the complex coupling braking process into independent control of hydraulic braking and regenerative braking, through which a balance between braking performance, braking reliability, braking safety and fuel economy is achieved. Simulation results show that the proposed strategy is effective and adaptable in different road conditions while the large wheel slip rate is triggered during a regenerative braking course. The research provides a new possibility of low-cost equipment and better control performance for the regenerative braking in the EV and the hybrid EV.

Progressing a human embryonic stem-cell-based regenerative medicine therapy towards the clinic.

Science.gov (United States)

Whiting, Paul; Kerby, Julie; Coffey, Peter; da Cruz, Lyndon; McKernan, Ruth

2015-10-19

Since the first publication of the derivation of human embryonic stem cells in 1998, there has been hope and expectation that this technology will lead to a wave of regenerative medicine therapies with the potential to revolutionize our approach to managing certain diseases. Despite significant resources in this direction, the path to the clinic for an embryonic stem-cell-based regenerative medicine therapy has not proven straightforward, though in the past few years progress has been made. Here, with a focus upon retinal disease, we discuss the current status of the development of such therapies. We also highlight some of our own experiences of progressing a retinal pigment epithelium cell replacement therapy towards the clinic. © 2015 The Author(s).

Regenerative Therapies for Diabetic Microangiopathy

Directory of Open Access Journals (Sweden)

Roberto Bassi

2012-01-01

Full Text Available Hyperglycaemia occurring in diabetes is responsible for accelerated arterial remodeling and atherosclerosis, affecting the macro- and the microcirculatory system. Vessel injury is mainly related to deregulation of glucose homeostasis and insulin/insulin-precursors production, generation of advanced glycation end-products, reduction in nitric oxide synthesis, and oxidative and reductive stress. It occurs both at extracellular level with increased calcium and matrix proteins deposition and at intracellular level, with abnormalities of intracellular pathways and increased cell death. Peripheral arterial disease, coronary heart disease, and ischemic stroke are the main causes of morbidity/mortality in diabetic patients representing a major clinical and economic issue. Pharmacological therapies, administration of growth factors, and stem cellular strategies are the most effective approaches and will be discussed in depth in this comprehensive review covering the regenerative therapies of diabetic microangiopathy.

Self-sustained cabinet based on fuel cell technology and solar energy

Energy Technology Data Exchange (ETDEWEB)

Correa, Rafael Augusto de Oliveira; Valentim, Rafael Bertier; Glir, Joao Raphael Zanlorensi; Stall, Alexandre; Sommer, Elise Meister; Sanches, Luciana Schimidilin; Dias, Fernando Gallego; Korndorfer, Heitor Medeiros de Albuquerque; Vargas, Jose Viriato Coelho [Universidade Federal do Parana (DEMEC/UFPR), Curitiba, PR (Brazil). Dept. de Engenharia Mecanica], Email: rafaelcorrea123@hotmail.com; Ordonez, Juan Carlos [Florida State University, Tallahasse, Florida (United States). Dept. of Mechanical Engineering. Center for Advanced Power Systems

2010-07-01

Along the past few years, there has been intensive research on clean and renewable energy production. Two main reasons have been pointed out: pollution caused by oil based fuels consumption and their availability diminution, which increases their production costs. Fuel Cells have shown to be a clean and renewable energy source, which reveals them as a promising solution, although their technology needs further development. Fuel Cells produce electricity, water and heat consuming hydrogen and oxygen, this provided pure or from a natural air source. Present research has combined different equipment to compose a self-sustaining fuel cells technology based cabinet for energy production, which is a Regenerative Fuel Cell System (RFC). This system contains: fuel cells stack, electrolyzer, photovoltaic panel, batteries, current inverter and a charge controller. Photovoltaic panel charges the batteries, while charge controller controls the batteries loading. Batteries are connected to an inverter which converts direct current into alternating current. Inverter is connected to an electrolyzer (Hogen GC 600) which splits the water molecule into hydrogen and oxygen molecules. Produced hydrogen supplies the fuel cell stack and the oxygen is released directly to the atmosphere. Fuel cell stacks power production is transformed into mechanical energy by a fan. Electrical power generated by Ballard stack is 5.124 W, with a voltage of 36.6 V and current of 0.14 A. The system proved to have a great efficiency and to be capable to assemble two renewable energy sources (solar and fuel cell technology) in a self-sustainable cabinet. It has also been shown that equipment such as Electrolyzer, Fuel Cell Stack and Photovoltaic panel can be fit together in the order to produce energy. Therefore, research on Fuel Cells Regenerative System reveals great importance for developing a new, clean, renewable and regenerative energy production system. (author)

Quantitative evaluation of RASSF1A methylation in the non-lesional, regenerative and neoplastic liver

Directory of Open Access Journals (Sweden)

Laghi Luigi

2006-04-01

Full Text Available Abstract Background Epigenetic changes during ageing and their relationship with cancer are under the focus of intense research. RASSF1A and NORE1A are novel genes acting in concert in the proapoptotic pathway of the RAS signalling. While NORE1A has not been previously investigated in the human liver, recent reports have suggested that RASSF1A is frequently epigenetically methylated not only in HCC but also in the cirrhotic liver. Methods To address whether epigenetic changes take place in connection to age and/or to the underlying disease, we investigated RASSF1A and NORE1A gene promoter methylation by conventional methylation specific PCR and Real-Time MSP in a series of hepatitic and non-hepatitic livers harboring regenerative/hyperplastic (cirrhosis/focal nodular hyperplasia, dysplastic (large regenerative, low and high grade dysplastic nodules and neoplastic (hepatocellular adenoma and carcinoma growths. Results In the hepatitic liver (chronic hepatitic/cirrhosis, hepatocellular nodules and HCC we found widespread RASSF1A gene promoter methylation with a methylation index that increased from regenerative conditions (cirrhosis to hepatocellular nodules (p RASSF1A gene promoter methylation, NORE1A gene was never found epigenetically alterated in both hepatitic and non-hepatitic liver. Conclusion We have shown that in non-lesional, regenerative and neoplastic liver the RASSF1A gene is increasingly methylated, that this condition takes place as an age-related phenomenon and that the early setting and spreading over time of an epigenetically methylated hepatocyte subpopulation, might be related to liver tumorigenesis.

Optimal regenerative braking with a push-belt CVT: an experimental study

NARCIS (Netherlands)

Berkel, van K.; Hofman, T.; Vroemen, B.G.; Steinbuch, M.

2010-01-01

This paper describes the approach and the results of efficiency experiments on a push-belt Continuously Variable Transmission (CVT) in a new hybrid drive train. The hybrid drive train uses the push-belt CVT to charge a flywheel, with the kinetic energy of the vehicle during regenerative braking and

Optimal regenerative braking with a push-belt CVT : an experimental study

NARCIS (Netherlands)

van Berkel, K.; Hofman, T.; Vroemen, B.; Steinbuch, M.

2010-01-01

This paper describes the approach and the results of efficiency experiments on a push-belt Continuously Variable Transmission (CVT) in a new hybrid drive train. The hybrid drive train uses the push-belt CVT to “charge” a flywheel, with the kinetic energy of the vehicle during regenerative braking

Design Analysis And Applications Of A Regenerative Bicycle Ergometer

Directory of Open Access Journals (Sweden)

Chukwuneke J. L.

2015-08-01

Full Text Available Man needs to do some form of physical work in other to remain healthy this work is similar to the work done by any machine or equipment and thus should be channeled to give useful output but rather it is usually dissipated into the environment in form of heat. The regenerative bicycle ergometer takes advantage of the greater power generated by the limbs and arms thus conserves converts and stores the energy dissipated by the rider with an ideal mechanical advantage of 7.6 it strategically uses simple mechanisms to magnify its work and then converts this mechanical energy into electrical energy by the use of a dynamo with a speed ratio of 108.5 and a transmission efficiency of 89 the rider pedals 27rpm to obtain the dynamos rated input of 2600rpm giving an output of 12.6volts. The regenerative bicycle ergometer is designed and constructed to perform all the core functions of a bicycle ergometer having an allowable load of 116.5kg and a maximum resistance of 65.33N which is equivalent to a mass of 6.66kg. The energy converted is stored in a 12volts battery making its use flexible clean and meeting the energy demands of man.

Three-dimensional bioprinting in tissue engineering and regenerative medicine.

Science.gov (United States)

Gao, Guifang; Cui, Xiaofeng

2016-02-01

With the advances of stem cell research, development of intelligent biomaterials and three-dimensional biofabrication strategies, highly mimicked tissue or organs can be engineered. Among all the biofabrication approaches, bioprinting based on inkjet printing technology has the promises to deliver and create biomimicked tissue with high throughput, digital control, and the capacity of single cell manipulation. Therefore, this enabling technology has great potential in regenerative medicine and translational applications. The most current advances in organ and tissue bioprinting based on the thermal inkjet printing technology are described in this review, including vasculature, muscle, cartilage, and bone. In addition, the benign side effect of bioprinting to the printed mammalian cells can be utilized for gene or drug delivery, which can be achieved conveniently during precise cell placement for tissue construction. With layer-by-layer assembly, three-dimensional tissues with complex structures can be printed using converted medical images. Therefore, bioprinting based on thermal inkjet is so far the most optimal solution to engineer vascular system to the thick and complex tissues. Collectively, bioprinting has great potential and broad applications in tissue engineering and regenerative medicine. The future advances of bioprinting include the integration of different printing mechanisms to engineer biphasic or triphasic tissues with optimized scaffolds and further understanding of stem cell biology.

Design and construction of a regenerative radiant tube burner

International Nuclear Information System (INIS)

Henao, Diego Alberto; Cano C, Carlos Andres; Amell Arrieta, Andres A.

2002-01-01

The technological development of the gas industry in Colombia, aiming at efficient and safe use of the natural gas, requires the assimilation and adaptation of new generation, technologies for this purpose in this article results are presented on the design, construction and characterization of a prototype of a burner of regenerative radiant robe with a thermal power of 9,94 kW and a factor of air 1,05. This system takes advantage of the high exit temperature of the combustion smokes, after they go trough a metallic robe where they transfer the heat by radiation, to heat a ceramic channel that has the capacity to absorbing a part of the heat of the smokes and then transferring them to a current of cold air. The benefits of air heating are a saving in fuel, compared with other processes that don't incorporate the recovery of heat from the combustion gases. In this work it was possible to probe a methodology for the design of this type of burners and to reach maximum temperatures of heating of combustion air of 377,9 centigrade degrees, using a material available in the national market, whose regenerative properties should be studied in depth

Performance and economic analysis of a plug and play regenerative brake for improving energy efficiency for traction elevators

Science.gov (United States)

Jeraputra, Chuttchaval; Tiptipakorn, Supun

2017-05-01

This paper presents performance and economic analysis of a plug and play regenerative brake for improving energy efficiency for traction elevators. The proposed regenerative brake recycles the energy loss of a dynamic brake and feeds into the grid while an elevator inverter is operating in the braking mode. According to field measurement of energy consumption, it reveals that the efficiency can be improved as much as 18%. The prototype of a regenerative brake 12 kW, 400V, 3ϕ is developed and tested on an elevator simulator. It is shown that it can transfer energy out of a DC capacitor before the dynamic brake kicks in. Further, an economic analysis is provided to carry out the payback period and the present worth equivalent to confirm economic feasibility.

Thermo- economical consideration of Regenerative organic Rankine cycle coupling with the absorption chiller systems incorporated in the trigeneration system

International Nuclear Information System (INIS)

Anvari, Simin; Taghavifar, Hadi; Parvishi, Alireza

2017-01-01

Highlights: • A new trigeneration cycle was studied from a new viewpoint of exergoeconomic and thermodynamic. • Organic Rankine and refrigeration cycles are used for recovery waste heat of cogeneration system. • Application of trigeneration cycles is advantageous in economical and thermodynamic aspects. - Abstract: In this paper, a combined cooling, heating and power cycle is proposed consisting of three sections of gas turbine and heat recovery steam generator cycle, Regenerative organic Rankine cycle, and absorption refrigeration cycle. This trigeneration cycle is subjected to a thorough thermodynamic and exergoeconomic analysis. The principal goal followed in the investigation is to address the thermodynamic and exergoeconomic of a trigeneration cycle from a new prospective such that the economic and thermodynamic viability of incorporating Regenerative organic Rankine cycle, and absorption refrigeration cycle to the gas turbine and heat recovery steam generator cycle is being investigated. Thus, the cost-effectiveness of the introduced method can be studied and further examined. The results indicate that adding Regenerative organic Rankine cycle to gas turbine and heat recovery steam generator cycle leads to 2.5% increase and the addition of absorption refrigeration cycle to the gas turbine and heat recovery steam generator/ Regenerative Organic Rankine cycle would cause 0.75% increase in the exergetic efficiency of the entire cycle. Furthermore, from total investment cost of the trigeneration cycle, only 5.5% and 0.45% results from Regenerative organic Rankine cycle and absorption refrigeration cycles, respectively.

Assessment of ASME code examinations on regenerative, letdown and residual heat removal heat exchangers

International Nuclear Information System (INIS)

Gosselin, Stephen R.; Cumblidge, Stephen E.; Anderson, Michael T.; Simonen, Fredric A.; Tinsley, G A.; Lydell, B.; Doctor, Steven R.

2005-01-01

Inservice inspection requirements for pressure retaining welds in the regenerative, letdown, and residual heat removal heat exchangers are prescribed in Section XI Articles IWB and IWC of the ASME Boiler and Pressure Vessel Code. Accordingly, volumetric and/or surface examinations are performed on heat exchanger shell, head, nozzle-to-head, and nozzle-to-shell welds. Inspection difficulties associated with the implementation of these Code-required examinations have forced operating nuclear power plants to seek relief from the U.S. Nuclear Regulatory Commission. The nature of these relief requests are generally concerned with metallurgical, geometry, accessibility, and radiation burden. Over 60% of licensee requests to the NRC identify significant radiation exposure burden as the principle reason for relief from the ASME Code examinations on regenerative heat exchangers. For the residual heat removal heat exchangers, 90% of the relief requests are associated with geometry and accessibility concerns. Pacific Northwest National Laboratory was funded by the NRC Office of Nuclear Regulatory Research to review current practice with regard to volumetric and/or surface examinations of shell welds of letdown heat exchangers regenerative heat exchangers and residual (decay) heat removal heat exchangers Design, operating, common preventative maintenance practices, and potential degradation mechanisms are reviewed. A detailed survey of domestic and international PWR-specific operating experience was performed to identify pressure boundary failures (or lack of failures) in each heat exchanger type and NSSS design. The service data survey was based on the PIPExp- database and covers PWR plants worldwide for the period 1970-2004. Finally a risk assessment of the current ASME Code inspection requirements for residual heat removal, letdown, and regenerative heat exchangers is performed. The results are then reviewed to discuss the examinations relative to plant safety and

Measurement of the equivalent dose in quartz using a regenerative-dose single-aliquot protocol

International Nuclear Information System (INIS)

Murray, A.S.; Roberts, R.G.

1998-01-01

The principles behind a regenerative-dose single-aliquot protocol are outlined. It is shown for three laboratory-bleached Australian sedimentary quartz samples that the relative change in sensitivity of the optically stimulated luminescence (OSL) during a repeated measurement cycle (consisting of a dose followed by a 10 s preheat at a given temperature and then a 100 s exposure to blue/green light at 125 deg. C) is very similar to that of the 110 deg. C thermoluminescence (TL) peak measured during the preheat cycle. The absolute change in the TL sensitivity with preheat temperature is different for samples containing a natural or a regenerative dose. Furthermore, the absolute change in sensitivity in both the OSL and TL signals is non-linear with regeneration cycle, but the relative change in the OSL signal compared to the following 110 deg. C TL measurement is well approximated by a straight line. Both signals are thought to use the same luminescence centres, and so some common behaviour is not unexpected. A new regenerative-dose protocol is presented which makes use of this linear relationship to correct for sensitivity changes with regeneration cycle, and requires only one aliquot for the estimation of the equivalent dose (D e ). The protocol has been applied to quartz from nine Australian sites. To illustrate the value of the regenerative-dose single-aliquot approach, the apparent values of D e for 13 samples, containing doses of between 0.01 and 100 Gy, have been measured at various preheat temperatures of between 160 and 300 deg. C, using a single aliquot for each D e measurement. Excellent agreement is found between these single-aliquot estimates of D e and those obtained from additive-dose multiple-aliquot and single-aliquot protocols, over the entire dose range

A helium regenerative compressor

International Nuclear Information System (INIS)

Swift, W.L.; Nutt, W.E.; Sixsmith, H.

1994-01-01

This paper discusses the design and performance of a regenerative compressor that was developed primarily for use in cryogenic helium systems. The objectives for the development were to achieve acceptable efficiency in the machine using conventional motor and bearing technology while reducing the complexity of the system required to control contamination from the lubricants. A single stage compressor was built and tested. The compressor incorporates aerodynamically shaped blades on a 218 mm (8.6 inches) diameter impeller to achieve high efficiency. A gas-buffered non-contact shaft seal is used to oppose the diffusion of lubricant from the motor bearings into the cryogenic circuit. Since it is a rotating machine, the flow is continuous and steady, and the machine is very quiet. During performance testing with helium, the single stage machine has demonstrated a pressure ratio of 1.5 at a flow rate of 12 g/s with measured isothermal efficiencies in excess of 30%. This performance compares favorably with efficiencies generally achieved in oil flooded screw compressors

On the genealogy of tissue engineering and regenerative medicine.

Science.gov (United States)

Kaul, Himanshu; Ventikos, Yiannis

2015-04-01

In this article, we identify and discuss a timeline of historical events and scientific breakthroughs that shaped the principles of tissue engineering and regenerative medicine (TERM). We explore the origins of TERM concepts in myths, their application in the ancient era, their resurgence during Enlightenment, and, finally, their systematic codification into an emerging scientific and technological framework in recent past. The development of computational/mathematical approaches in TERM is also briefly discussed.

Leaf and shoot water content and leaf dry matter content of Mediterranean woody species with different post-fire regenerative strategies.

Science.gov (United States)

Saura-Mas, S; Lloret, F

2007-03-01

Post-fire regeneration is a key process in Mediterranean shrubland dynamics, strongly determining the functional properties of the community. In this study, a test is carried out to determine whether there is co-variation between species regenerative types and functional attributes related to water use. An analysis was made of the seasonal variations in leaf relative water content (RWC), leaf dry matter content (LDMC), leaf moisture (LM) and live fine fuel moisture (LFFM) in 30 woody species of a coastal shrubland, with different post-fire regenerative strategies (seeding, resprouting or both). RWC results suggest that the studied resprouters have more efficient mechanisms to reduce water losses and maintain water supply between seasons. In contrast, seeders are more drought tolerant. LDMC is higher in resprouters over the course of the year, suggesting a more efficient conservation of nutrients. The weight of the phylogenetic constraint to understand differences between regenerative strategies tends to be important for LDMC, while it is not the case for variables such as RWC. Groups of species with different post-fire regenerative strategies (seeders and resprouters) have different functional traits related to water use. In addition to the role of phylogenetical constraints, these differences are also likely to be related to the respective life history characteristics. Therefore, the presence and abundance of species with different post-fire regenerative responses influence the functional properties of the communities.

Tissue Engineering in Regenerative Dental Therapy

Directory of Open Access Journals (Sweden)

Hiral Jhaveri-Desai

2011-01-01

Full Text Available Tissue engineering is amongst the latest exciting technologies having impacted the field of dentistry. Initially considered as a futuristic approach, tissue engineering is now being successfully applied in regenerative surgery. This article reviews the important determinants of tissue engineering and how they contribute to the improvement of wound healing and surgical outcomes in the oral region. Furthermore, we shall address the clinical applications of engineering involving oral and maxillofacial surgical and periodontal procedures along with other concepts that are still in experimental phase of development. This knowledge will aid the surgical and engineering researchers to comprehend the collaboration between these fields leading to extounding dental applications and to ever-continuing man-made miracles in the field of human science.

Plug and play: combining materials and technologies to improve bone regenerative strategies

NARCIS (Netherlands)

Moroni, Lorenzo; Nandakumar, A.; Barrère, F.; van Blitterswijk, Clemens; Habibovic, Pamela

2015-01-01

Despite recent advances in the development of biomaterials intended to replace natural bone grafts for the regeneration of large, clinically relevant defects, most synthetic solutions that are currently applied in the clinic are still inferior to natural bone grafts with regard to regenerative

Current concepts: tissue engineering and regenerative medicine applications in the ankle joint

NARCIS (Netherlands)

Correia, S. I.; Pereira, H.; Silva-Correia, J.; van Dijk, C. N.; Espregueira-Mendes, J.; Oliveira, J. M.; Reis, R. L.

2014-01-01

Tissue engineering and regenerative medicine (TERM) has caused a revolution in present and future trends of medicine and surgery. In different tissues, advanced TERM approaches bring new therapeutic possibilities in general population as well as in young patients and high-level athletes, improving

Elixir of Life: Thwarting Aging With Regenerative Reprogramming.

Science.gov (United States)

Beyret, Ergin; Martinez Redondo, Paloma; Platero Luengo, Aida; Izpisua Belmonte, Juan Carlos

2018-01-05

All living beings undergo systemic physiological decline after ontogeny, characterized as aging. Modern medicine has increased the life expectancy, yet this has created an aged society that has more predisposition to degenerative disorders. Therefore, novel interventions that aim to extend the healthspan in parallel to the life span are needed. Regeneration ability of living beings maintains their biological integrity and thus is the major leverage against aging. However, mammalian regeneration capacity is low and further declines during aging. Therefore, modalities that reinforce regeneration can antagonize aging. Recent advances in the field of regenerative medicine have shown that aging is not an irreversible process. Conversion of somatic cells to embryonic-like pluripotent cells demonstrated that the differentiated state and age of a cell is not fixed. Identification of the pluripotency-inducing factors subsequently ignited the idea that cellular features can be reprogrammed by defined factors that specify the desired outcome. The last decade consequently has witnessed a plethora of studies that modify cellular features including the hallmarks of aging in addition to cellular function and identity in a variety of cell types in vitro. Recently, some of these reprogramming strategies have been directly used in animal models in pursuit of rejuvenation and cell replacement. Here, we review these in vivo reprogramming efforts and discuss their potential use to extend the longevity by complementing or augmenting the regenerative capacity. © 2017 American Heart Association, Inc.

Regenerative Medicine for Periodontal and Peri-implant Diseases.

Science.gov (United States)

Larsson, L; Decker, A M; Nibali, L; Pilipchuk, S P; Berglundh, T; Giannobile, W V

2016-03-01

The balance between bone resorption and bone formation is vital for maintenance and regeneration of alveolar bone and supporting structures around teeth and dental implants. Tissue regeneration in the oral cavity is regulated by multiple cell types, signaling mechanisms, and matrix interactions. A goal for periodontal tissue engineering/regenerative medicine is to restore oral soft and hard tissues through cell, scaffold, and/or signaling approaches to functional and aesthetic oral tissues. Bony defects in the oral cavity can vary significantly, ranging from smaller intrabony lesions resulting from periodontal or peri-implant diseases to large osseous defects that extend through the jaws as a result of trauma, tumor resection, or congenital defects. The disparity in size and location of these alveolar defects is compounded further by patient-specific and environmental factors that contribute to the challenges in periodontal regeneration, peri-implant tissue regeneration, and alveolar ridge reconstruction. Efforts have been made over the last few decades to produce reliable and predictable methods to stimulate bone regeneration in alveolar bone defects. Tissue engineering/regenerative medicine provide new avenues to enhance tissue regeneration by introducing bioactive models or constructing patient-specific substitutes. This review presents an overview of therapies (e.g., protein, gene, and cell based) and biomaterials (e.g., resorbable, nonresorbable, and 3-dimensionally printed) used for alveolar bone engineering around teeth and implants and for implant site development, with emphasis on most recent findings and future directions. © International & American Associations for Dental Research 2015.

Gingival cyst of the adult: regenerative therapy of associated root exposure. A case report and literature review.

Science.gov (United States)

Kelsey, W Patrick; Kalmar, John R; Tatakis, Dimitris N

2009-12-01

The gingival cyst of the adult (GCA) is an uncommon developmental cyst of odontogenic origin most frequently seen near mandibular canines and premolars and is routinely treated with excisional biopsy. This article presents a case of a GCA treated with a combined regenerative approach and reviews the GCA literature with an emphasis on the clinical aspects of this lesion. A 54 year-old man presented for treatment of generalized severe chronic periodontitis. Clinical examination revealed a cystic lesion in the gingiva of the mandibular canine-premolar area. Radiographs revealed a well-defined radiolucency in the coronal one-third of the tooth roots. Surgical enucleation of the lesion revealed root exposure of the second premolar. Because of the anatomy of the lesion-associated defect, regenerative treatment, using a combination of freeze-dried bone allograft and a collagen membrane, was considered the therapeutic approach of choice. The biopsy revealed histologic features consistent with a GCA. Clinical and radiographic examinations 1 year post-surgery indicated uneventful soft tissue healing and bone fill of the initial defect. The review of the literature revealed only one other case of root exposure associated with GCA and no previous report of regenerative therapy. In rare instances, a GCA lesion may result in tooth-root exposure. In such cases, a combined regenerative treatment approach may be used to achieve resolution.

Advanced Tissue Sciences Inc.: learning from the past, a case study for regenerative medicine.

Science.gov (United States)

Pangarkar, Nitin; Pharoah, Marc; Nigam, Avinav; Hutmacher, Dietmar W; Champ, Simon

2010-09-01

On 31st March 2003 Advanced Tissue Sciences (ATS) was liquidated, with the effect that in excess of US$300 million of stakeholder financing was destroyed. Although successful in the development of breakthrough technologies in the regenerative medicine arena and the building of a substantial portfolio of patents, the company never made a profit. In this case study, ATS’ business strategy, market and competitive environment will be discussed in the context of the company’s historical development. A number of important lessons from this case are discussed. From a management perspective the most critical lesson is the importance of effective financial planning and management of costs, and in particular R&D costs, including the significant costs associated with clinical trials. In addition, a clear strategic focus is extremely important due to the significant resources required in the development of a new therapy. From an investor’s perspective the lessons to be gathered from the ATS case are related to the risk involved in investing in the field of regenerative medicine. This case indicates that both professional and private investors did not fully question the validity of ATS’ business strategy and financial forecasts. A clear and focused strategy based on long-term investor commitment is essential for the successful commercialization of regenerative medicine.

Fetal skeletal muscle progenitors have regenerative capacity after intramuscular engraftment in dystrophin deficient mice.

Directory of Open Access Journals (Sweden)

Hiroshi Sakai

Full Text Available Muscle satellite cells (SCs are stem cells that reside in skeletal muscles and contribute to regeneration upon muscle injury. SCs arise from skeletal muscle progenitors expressing transcription factors Pax3 and/or Pax7 during embryogenesis in mice. However, it is unclear whether these fetal progenitors possess regenerative ability when transplanted in adult muscle. Here we address this question by investigating whether fetal skeletal muscle progenitors (FMPs isolated from Pax3(GFP/+ embryos have the capacity to regenerate muscle after engraftment into Dystrophin-deficient mice, a model of Duchenne muscular dystrophy. The capacity of FMPs to engraft and enter the myogenic program in regenerating muscle was compared with that of SCs derived from adult Pax3(GFP/+ mice. Transplanted FMPs contributed to the reconstitution of damaged myofibers in Dystrophin-deficient mice. However, despite FMPs and SCs having similar myogenic ability in culture, the regenerative ability of FMPs was less than that of SCs in vivo. FMPs that had activated MyoD engrafted more efficiently to regenerate myofibers than MyoD-negative FMPs. Transcriptome and surface marker analyses of these cells suggest the importance of myogenic priming for the efficient myogenic engraftment. Our findings suggest the regenerative capability of FMPs in the context of muscle repair and cell therapy for degenerative muscle disease.

Performance analysis of underlay cognitive multihop regenerative relaying systems with multiple primary receivers

KAUST Repository

Hyadi, Amal; Benjillali, Mustapha; Alouini, Mohamed-Slim; Da Costa, Daniel Benevides Da

2013-01-01

Multihop relaying is an efficient strategy to improve the connectivity and extend the coverage area of secondary networks in underlay cognitive systems. In this work, we provide a comprehensive performance study of cognitive multihop regenerative

Influence of environmental conditions on the regenerative capacity and the survivability of Elodea nuttallii fragments

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Markus A. Hoffmann

2014-06-01

Full Text Available The presented study was conducted to determine which environmental factors and conditions can affect the regenerative capacity and survivability of Elodea nuttallii [o1] and therefore the efficiency of mechanical management methods like cutting and harvesting. The influence of water temperature, light intensity and nutrient concentration in the sediment on the survivability and regenerative capacity of the invasive species E. nuttallii was determined in three laboratory and one field experiments. E. nuttallii fragments with one to four nodes were stored in aquaria under constant temperature and/or light conditions. To examine the influence of water temperature, four aquaria were kept at a constant water temperature of either 15°C or 20°C. The influence of light intensity was studied by shading the aquaria with different types of mesh. The fragments were stored at constant light intensities of 215, 161, 86 and 31 µmol photons m–2 s–1. Fragments in aquaria filled with sediment with 20 µg P2O5-P g–1 soil, 150 µg P2O5-P g–1 soil or without sediment were studied to determine the influence of the sediment. The results of the laboratory experiments showed how the mechanical management methods are most efficient during periods with low water temperatures, high turbidity or low global irradiation and nutrient poor waters. The field experiment was designed to study the influence of the nutrient compositions in the sediment on the growth and regenerative capacity of rooted E. nuttallii. E. nuttallii fragments were planted in compartments treated with PO43-- and/or NH4+-fertiliser and were trimmed after six weeks. The experiment revealed that the growth before a harvest and the growth after a harvest (regenerative capacity differ significantly, depending on the nutrient composition in the substrate. An increase of the PO43- concentration in the sediment, for example, reduced the growth of E. nuttallii before the harvest, but increased the

Tissue engineering and microRNAs: future perspectives in regenerative medicine.

Science.gov (United States)

Gori, Manuele; Trombetta, Marcella; Santini, Daniele; Rainer, Alberto

2015-01-01

Tissue engineering is a growing area of biomedical research, holding great promise for a broad range of potential applications in the field of regenerative medicine. In recent decades, multiple tissue engineering strategies have been adopted to mimic and improve specific biological functions of tissues and organs, including biomimetic materials, drug-releasing scaffolds, stem cells, and dynamic culture systems. MicroRNAs (miRNAs), noncoding small RNAs that negatively regulate the expression of downstream target mRNAs, are considered a novel class of molecular targets and therapeutics that may play an important role in tissue engineering. Herein, we highlight the latest achievements in regenerative medicine, focusing on the role of miRNAs as key modulators of gene expression, stem cell self-renewal, proliferation and differentiation, and eventually in driving cell fate decisions. Finally, we will discuss the contribution of miRNAs in regulating the rearrangement of the tissue microenvironment and angiogenesis, and the range of strategies for miRNA delivery into target cells and tissues. Manipulation of miRNAs is an alternative approach and an attractive strategy for controlling several aspects of tissue engineering, although some issues concerning their in vivo effects and optimal delivery methods still remain uncovered.

Regenerative nanotechnology in oral and maxillofacial surgery.

Science.gov (United States)

Shakib, Kaveh; Tan, Aaron; Soskic, Vukic; Seifalian, Alexander M

2014-12-01

Regenerative nanotechnology is at the forefront of medical research, and translational medicine is a challenge to both scientists and clinicians. Although there has been an exponential rise in the volume of research generated about it for both medical and surgical uses, key questions remain about its actual benefits. Nevertheless, some people think that therapeutics based on its principles may form the core of applied research for the future. Here we give an account of its current use in oral and maxillofacial surgery, and implications and challenges for the future. Copyright © 2014 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Feasibility investigation of allogeneic endometrial regenerative cells

Directory of Open Access Journals (Sweden)

Reid Michael

2009-02-01

Full Text Available Abstract Endometrial Regenerative Cells (ERC are a population of mesenchymal-like stem cells having pluripotent differentiation activity and ability to induce neoangiogenesis. In vitro and animal studies suggest ERC are immune privileged and in certain situations actively suppress ongoing immune responses. In this paper we describe the production of clinical grade ERC and initial safety experiences in 4 patients with multiple sclerosis treated intravenously and intrathecally. The case with the longest follow up, of more than one year, revealed no immunological reactions or treatment associated adverse effects. These preliminary data suggest feasibility of clinical ERC administration and support further studies with this novel stem cell type.

DNA Methylation Dynamics Regulate the Formation of a Regenerative Wound Epithelium during Axolotl Limb Regeneration.

Directory of Open Access Journals (Sweden)

Cristian Aguilar

Full Text Available The formation of a blastema during regeneration of an axolotl limb involves important changes in the behavior and function of cells at the site of injury. One of the earliest events is the formation of the wound epithelium and subsequently the apical epidermal cap, which involves in vivo dedifferentiation that is controlled by signaling from the nerve. We have investigated the role of epigenetic modifications to the genome as a possible mechanism for regulating changes in gene expression patterns of keratinocytes of the wound and blastema epithelium that are involved in regeneration. We report a modulation of the expression DNMT3a, a de novo DNA methyltransferase, within the first 72 hours post injury that is dependent on nerve signaling. Treatment of skin wounds on the upper forelimb with decitabine, a DNA methyltransferase inhibitor, induced changes in gene expression and cellular behavior associated with a regenerative response. Furthermore, decitabine-treated wounds were able to participate in regeneration while untreated wounds inhibited a regenerative response. Elucidation of the specific epigenetic modifications that mediate cellular dedifferentiation likely will lead to insights for initiating a regenerative response in organisms that lack this ability.

Stationary super-capacitor energy storage system to save regenerative braking energy in a metro line

International Nuclear Information System (INIS)

Teymourfar, Reza; Asaei, Behzad; Iman-Eini, Hossein; Nejati fard, Razieh

2012-01-01

Highlights: ► Super-capacitors are used to store regenerative braking energy in a metro network. ► A novel approach is proposed to model easily and accurately the metro network. ► An efficient approach is proposed to calculate the required super-capacitors. ► Maximum energy saving is around 44% at off-peak period and 42% at peak period. ► Benefit/cost analyses are performed for the suggested ESS. - Abstract: In this paper, the stationary super-capacitors are used to store a metro network regenerative braking energy. In order to estimate the required energy storage systems (ESSs), line 3 of Tehran metro network is modeled through a novel approach, in peak and off-peak conditions based on the real data obtained from Tehran metro office. A useful method is proposed to predict the maximum instantaneous regenerative energy which is delivered to each station before applying ESS and based on that the ESS configuration for each station is determined. Finally, the effectiveness of the proposed ESS is confirmed by economic evaluations and benefit/cost analyses on line 3 of Tehran metro network.

Regenerative Medicine as an Emergent Cluster in Tampere Region

Directory of Open Access Journals (Sweden)

Tuomo Heinonen

2015-01-01

Full Text Available Clusters are important for regional economies and emergent clusters are in a key position, as a means of adding more diversification to the current economic activity by involving new technologies and industries. Science-based industries may be the most promising in this regard since they are encouraged to develop and enhance the economic imaginaries of territories under the umbrella of radical innovations or in the name of broadening the current economic model based on mostly traditional industries. Regenerative medicine (RM could be an example of these so-called emergent clusters. Regenerative medicine is highly dependent on academic research, which means that local territories must fund the research in this field and, hence, they expect some returns as well. As territories do not typically have existing industries specifically in RM, these industries must emerge or expand from existing ones. Regenerative medicine involves a wide spectrum of different technologies and industries that are likely to form a cluster and benefit from it if successfully developed. The first aim of this paper is to show how some obstacles eventually impede the proper development of these emergent clusters. The second aim is to shed light on how innovations emerge in the cluster and what are the main implications for the territory. In this study, existing literature is used in order to describe the technology market and commercial aspects of the RM sector. Empirically this study is based on the emergent RM cluster in the region of Tampere in Finland. Analysis of 24 conducted interviews helps to contextualize the emergence of the RM cluster in Tampere, where academia is both the booster and the driver of the emergent RM cluster. Commercialization of research in the RM field is one of the goals at the university, even though there are no commercial outcomes yet available. This study contributes to the understanding of emergent cluster development in science

Research on Modeling and Control of Regenerative Braking for Brushless DC Machines Driven Electric Vehicles

Directory of Open Access Journals (Sweden)

Jian-ping Wen

2015-01-01

Full Text Available In order to improve energy utilization rate of battery-powered electric vehicle (EV using brushless DC machine (BLDCM, the model of braking current generated by regenerative braking and control method are discussed. On the basis of the equivalent circuit of BLDCM during the generative braking period, the mathematic model of braking current is established. By using an extended state observer (ESO to observe actual braking current and the unknown disturbances of regenerative braking system, the autodisturbances rejection controller (ADRC for controlling the braking current is developed. Experimental results show that the proposed method gives better recovery efficiency and is robust to disturbances.

Potential feasibility of dental stem cells for regenerative therapies: stem cell transplantation and whole-tooth engineering.

Science.gov (United States)

Nakahara, Taka

2011-07-01

Multipotent mesenchymal stem cells from bone marrow are expected to be a somatic stem cell source for the development of new cell-based therapy in regenerative medicine. However, dental clinicians are unlikely to carry out autologous cell/tissue collection from patients (i.e., marrow aspiration) as a routine procedure in their clinics; hence, the utilization of bone marrow stem cells seems impractical in the dental field. Dental tissues harvested from extracted human teeth are well known to contain highly proliferative and multipotent stem cell compartments and are considered to be an alternative autologous cell source in cell-based medicine. This article provides a short overview of the ongoing studies for the potential application of dental stem cells and suggests the utilization of 2 concepts in future regenerative medicine: (1) dental stem cell-based therapy for hepatic and other systemic diseases and (2) tooth replacement therapy using the bioengineered human whole tooth, called the "test-tube dental implant." Regenerative therapies will bring new insights and benefits to the fields of clinical medicine and dentistry.

Regenerative liver surgeries: the alphabet soup of emerging techniques.

Science.gov (United States)

Parekh, Maansi; Kluger, Michael D; Griesemer, Adam; Bentley-Hibbert, Stuart

2016-01-01

New surgical procedures taking advantage of the regenerative abilities of the liver are being introduced as potential curative therapies to these patients either to provide auxiliary support while the native liver recovers or undergoes hypertrophy. For patients with hepatocellular carcinoma outside of the Milan criteria or bilobar colorectal metastases liver transplantation is not an option. Fulminant hepatic failure can be treated but requires life-long immunosuppression. These complex surgical procedures require high quality and directed imaging.

Exploring the Potentials of ICT Tools for Human-Centric Regenerative Design

Directory of Open Access Journals (Sweden)

Giulia Sonetti

2018-04-01

Full Text Available Aiming for sustainable buildings and cities is critical to achieving a future that is socially just, ecologically regenerative, culturally rich, and economically viable. However, our current concepts of sustainability often exclude the essential domains of data, information, and the knowledge relating to the relationship between buildings and people that inhabit them. Thus, the research questions at the core of this paper have been as follows: Can technologies and artificial intelligence (AI be used to create systems that enhance relationships between buildings and inhabitants? Can social networks and natural interactions support further research relating to human-centric design tools for the built environment? The Human Observation Meta-Environment (HOME project was developed to address this question. The ICT architecture has been tested to observe and collect human behaviour data within a sentient room at the Politecnico di Torino (IT, where the inhabitants were strategically aware of their behaviours. Methods of analysis included technologies related to the domain of AI (such as Natural Language Analysis, Computer Vision, Machine Learning and Deep Learning that have been used in social network analysis in connection with the word ‘comfort’, and definitions resonate strongly with the realm of regenerative design. Results were used to further research the role of users that could serve as leverages to design (both spaces and related smart systems according to actual user needs. People from very different disciplinary backgrounds interacted with the prototype in a workshop and provided stimuli for further considerations regarding the possible technological, psychological, cognitive, cultural, social, political, and aesthetical impacts of the use of these technologies inside sentient buildings. The paper enriches the discourse on how ICT data can be organised and read in a human-centric regenerative design process perspective.

An overview of periodontal regenerative procedures for the general dental practitioner

Directory of Open Access Journals (Sweden)

M. Siaili

2018-01-01

Full Text Available The complete regeneration of the periodontal tissues following periodontal disease remains an unmet challenge, and has presented clinicians with a remarkably difficult clinical challenge to solve given the extensive research in this area and our current understanding of the biology of the periodontal tissues. In particular as clinicians we look for treatments that will improve the predictability of the procedure, improve the magnitude of the effect of treatment, and perhaps most importantly in the long term would extend the indications for treatment beyond the need for single enclosed bony defects to allow for suprabony regeneration, preferably with beneficial effects on the gingival soft tissues. A rapid development in both innovative methods and products for the correction of periodontal deficiencies have been reported during the last three decades. For example, guided tissue regeneration with or without the use of bone supplements has been a well-proven treatment modality for the reconstruction of bony defects prior to the tissue engineering era. Active biomaterials have been subsequently introduced to the periodontal community with supporting dental literature suggesting that certain factors should be taken into consideration when undertaking periodontal regenerative procedures. These factors as well as a number of other translational research issues will need to be addressed, and ultimately it is vital that we do not extrapolate results from pre-clinical and animal studies without conducting extensive randomized clinical trials to substantiate outcomes from these procedures. Whatever the outcomes, the pursuit of regeneration of the periodontal tissues remains a goal worth pursuing for our patients. The aim of the review, therefore is to update clinicians on the recent advances in both materials and techniques in periodontal regenerative procedures and to highlight the importance of both patient factors and the technical aspects of

78 FR 43889 - Synergizing Efforts in Standards Development for Cellular Therapies and Regenerative Medicine...

Science.gov (United States)

2013-07-22

... regenerative medicine products have generated a great deal of interest. These efforts include standards... is done to coordinate the various existing efforts. In the public workshop, FDA hopes to bring...

Application of human amniotic mesenchymal cells as an allogeneic transplantation cell source in bone regenerative therapy

International Nuclear Information System (INIS)

Tsuno, Hiroaki; Yoshida, Toshiko; Nogami, Makiko; Koike, Chika; Okabe, Motonori; Noto, Zenko; Arai, Naoya; Noguchi, Makoto; Nikaido, Toshio

2012-01-01

Autogenous mesenchymal stem cells (MSCs) have therapeutic applications in bone regenerative therapy due to their pluripotency. However, the ability of MSCs to proliferate and differentiate varies between donors. Furthermore, alternative sources of MSCs are required for patients with contraindications to autogenous cell therapy. The aim of this study was to evaluate the potential of mesenchymal cells from the human amniotic membrane (HAM) as a source of cells for allogeneic transplantation in bone regenerative therapy. Cells that retained a proliferative capacity of more than 50 population doubling level were distinguished from other HAM cells as HAMα cells and induced to osteogenic status—their in vivo osteogenesis was subsequently investigated in rats. It was found that HAMα cells were spindle shaped and were positive for MSC markers and negative for hematopoietic stem cell markers. Alkaline phosphatase activity and calcium deposition increased with osteogenic status of HAMα cells. The expression of osteocalcin mRNA was increased in HAMα cells cultured on calcium phosphate scaffolds. Moreover, xenografted HAMα cells remained viable and produced extracellular matrix for several weeks. Thus, this study suggests that human amniotic mesenchymal cells possess osteogenic differentiation potential and could be applied to allogeneic transplantation in bone regenerative therapy. - Highlights: ► Human amniotic mesenchymal cells include cells (HAMα cells) that have the properties of MSCs. ► HAMα cells have excellent osteogenic differentiation potential. ► Osteogenic differentiation ability of HAMα was amplified by calcium phosphate scaffolds. ► HAMα cells can be applicable to allogeneic cell transplantation in bone regenerative therapy.

Regenerative therapy and tissue engineering for the treatment of end-stage cardiac failure: new developments and challenges.

Science.gov (United States)

Finosh, G T; Jayabalan, Muthu

2012-01-01

Regeneration of myocardium through regenerative therapy and tissue engineering is appearing as a prospective treatment modality for patients with end-stage heart failure. Focusing on this area, this review highlights the new developments and challenges in the regeneration of myocardial tissue. The role of various cell sources, calcium ion and cytokine on the functional performance of regenerative therapy is discussed. The evolution of tissue engineering and the role of tissue matrix/scaffold, cell adhesion and vascularisation on tissue engineering of cardiac tissue implant are also discussed.

The early career researcher's toolkit: translating tissue engineering, regenerative medicine and cell therapy products.

Science.gov (United States)

Rafiq, Qasim A; Ortega, Ilida; Jenkins, Stuart I; Wilson, Samantha L; Patel, Asha K; Barnes, Amanda L; Adams, Christopher F; Delcassian, Derfogail; Smith, David

2015-11-01

Although the importance of translation for the development of tissue engineering, regenerative medicine and cell-based therapies is widely recognized, the process of translation is less well understood. This is particularly the case among some early career researchers who may not appreciate the intricacies of translational research or make decisions early in development which later hinders effective translation. Based on our own research and experiences as early career researchers involved in tissue engineering and regenerative medicine translation, we discuss common pitfalls associated with translational research, providing practical solutions and important considerations which will aid process and product development. Suggestions range from effective project management, consideration of key manufacturing, clinical and regulatory matters and means of exploiting research for successful commercialization.

Hurdles in tissue engineering/regenerative medicine product commercialization: a pilot survey of governmental funding agencies and the financial industry.

Science.gov (United States)

Bertram, Timothy A; Tentoff, Edward; Johnson, Peter C; Tawil, Bill; Van Dyke, Mark; Hellman, Kiki B

2012-11-01

The Tissue Engineering and Regenerative Medicine International Society of the Americas (TERMIS-AM) Industry Committee conducted a semiquantitative opinion survey in 2010 to delineate potential hurdles to commercialization perceived by the TERMIS constituency groups that participate in the stream of technology commercialization (academia, start-up companies, development-stage companies, and established companies). A significant hurdle identified consistently by each group was access to capital for advancing potential technologies into development pathways leading to commercialization. A follow-on survey was developed by the TERMIS-AM Industry Committee to evaluate the financial industry's perspectives on investing in regenerative medical technologies. The survey, composed of 15 questions, was developed and provided to 37 investment organizations in one of three sectors (governmental, private, and public investors). The survey was anonymous and confidential with sector designation the only identifying feature of each respondent's organization. Approximately 80% of the survey was composed of respondents from the public (n=14) and private (n=15) sectors. Each respondent represents one investment organization with the potential of multiple participants participating to form the organization's response. The remaining organizations represented governmental agencies (n=8). Results from this survey indicate that a high percentage ($2MM into regenerative medical companies at the different stages of a company's life cycle. Investors recognized major hurdles to this emerging industry, including regulatory pathway, clinical translation, and reimbursement of these new products. Investments in regenerative technologies have been cyclical over the past 10-15 years, but investors recognized a 1-5-year investment period before the exit via Merger and Acquisition (M&A). Investors considered musculoskeletal products and their top technology choice with companies in the clinical stage

Regenerative endodontic treatment for necrotic immature permanent premolar: A report of case

Directory of Open Access Journals (Sweden)

Sheetal B Ghivari

2017-01-01

Full Text Available Regenerative endodontic procedures provide new hope of converting nonvital tooth into vital once again. These potential regenerative approaches include root canal revascularization, postnatal stem-cell therapy, pulp implant, scaffold implant, three-dimensional cell printing, injectable scaffolds, and gene therapy. In this article, we describe successful revascularization treatment of necrotic permanent premolar tooth. Clinical and radiographic examination showed pulp involvement due to deep pit defect and periapical infection. Examination findings suggested revascularization treatment which was started with irrigation of canals using 1.25% of sodium hypochlorite and saline, followed by placement of 3-week dressing of triple antibiotic paste (ciprofloxacin, metronidazole, and minocycline. After removal of triple antibiotic paste blood clot was induced and mineral trioxide aggregate was placed on the blood clot followed by sealing the canal with glass ionomer cement. During radiographic and clinical follow-ups, the patient was asymptomatic and periapical lesion was healed, roots continued to develop, and root apex maturogenesis was complete.

A regenerative zinc-air fuel cell

Energy Technology Data Exchange (ETDEWEB)

Smedley, Stuart I. [Electrochemical Technology Development Ltd., Lower Hutt (New Zealand); Zhang, X. Gregory [Teck Cominco Metals Ltd., 2380 Speakman Drive, Mississauga, Ontario (Canada)

2007-03-20

The zinc regenerative fuel cell (ZRFC) developed by the former Metallic Power Inc. over the period from 1998 to 2004 is described. The component technologies and engineering solutions for various technical issues are discussed in relation to their functionality in the system. The system was designed to serve as a source of backup emergency power for remote or difficult to access cell phone towers during periods when the main power was interrupted. It contained a 12 cell stack providing 1.8 kW, a separate fuel tank containing zinc pellet fuel and electrolyte, and a zinc electrolyzer to regenerate the zinc pellets during standby periods. Offsite commissioning and testing of the system was successfully performed. The intellectual property of the ZRFC technology is now owned by Teck Cominco Metals Ltd. (author)

All-Optical Regenerative OTDM Add/Drop Multiplexing at 40 Gbit/s using Monolithic InP Mach-Zehnder Interferometer

DEFF Research Database (Denmark)

Buxens, Alvaro A.; Clausen, Anders; Poulsen, Henrik Nørskov

2000-01-01

We report a novel method for simultaneous add-drop multiplexing in OTDM systems which includes regenerative capabilities and perfect clearing of the drop channel time slot. The principle has been demonstrated at 40 Gb/s showing an excellent performance.......We report a novel method for simultaneous add-drop multiplexing in OTDM systems which includes regenerative capabilities and perfect clearing of the drop channel time slot. The principle has been demonstrated at 40 Gb/s showing an excellent performance....

Investigation of bio-regenerative life support and Trash-to-gas experiment on a 4 month mars simulation mission

OpenAIRE

Caraccio, A.; Poulet, Lucie; Hintze, P.; Miles, J.D.

2014-01-01

Future crewed missions to other planets or deep space locations will require regenerative Life Support Systems (LSS) as well as recycling processes for mission waste. Constant resupply of many commodity materials will not be a sustainable option for deep space missions, nor will stowing trash on board a vehicle or at a lunar or Martian outpost. The habitable volume will decline as the volume of waste increases. A complete regenerative environmentally controlled life support system (ECLSS) on ...

A regenerative elastocaloric heat pump

Science.gov (United States)

Tušek, Jaka; Engelbrecht, Kurt; Eriksen, Dan; Dall'Olio, Stefano; Tušek, Janez; Pryds, Nini

2016-10-01

A large fraction of global energy use is for refrigeration and air-conditioning, which could be decarbonized if efficient renewable energy technologies could be found. Vapour-compression technology remains the most widely used system to move heat up the temperature scale after more than 100 years; however, caloric-based technologies (those using the magnetocaloric, electrocaloric, barocaloric or elastocaloric effect) have recently shown a significant potential as alternatives to replace this technology due to high efficiency and the use of green solid-state refrigerants. Here, we report a regenerative elastocaloric heat pump that exhibits a temperature span of 15.3 K on the water side with a corresponding specific heating power up to 800 W kg-1 and maximum COP (coefficient-of-performance) values of up to 7. The efficiency and specific heating power of this device exceeds those of other devices based on caloric effects. These results open up the possibility of using the elastocaloric effect in various cooling and heat-pumping applications.

Tissue-engineering-based Strategies for Regenerative Endodontics

Science.gov (United States)

Albuquerque, M.T.P.; Valera, M.C.; Nakashima, M.; Nör, J.E.; Bottino, M.C.

2014-01-01

Stemming from in vitro and in vivo pre-clinical and human models, tissue-engineering-based strategies continue to demonstrate great potential for the regeneration of the pulp-dentin complex, particularly in necrotic, immature permanent teeth. Nanofibrous scaffolds, which closely resemble the native extracellular matrix, have been successfully synthesized by various techniques, including but not limited to electrospinning. A common goal in scaffold synthesis has been the notion of promoting cell guidance through the careful design and use of a collection of biochemical and physical cues capable of governing and stimulating specific events at the cellular and tissue levels. The latest advances in processing technologies allow for the fabrication of scaffolds where selected bioactive molecules can be delivered locally, thus increasing the possibilities for clinical success. Though electrospun scaffolds have not yet been tested in vivo in either human or animal pulpless models in immature permanent teeth, recent studies have highlighted their regenerative potential both from an in vitro and in vivo (i.e., subcutaneous model) standpoint. Possible applications for these bioactive scaffolds continue to evolve, with significant prospects related to the regeneration of both dentin and pulp tissue and, more recently, to root canal disinfection. Nonetheless, no single implantable scaffold can consistently guide the coordinated growth and development of the multiple tissue types involved in the functional regeneration of the pulp-dentin complex. The purpose of this review is to provide a comprehensive perspective on the latest discoveries related to the use of scaffolds and/or stem cells in regenerative endodontics. The authors focused this review on bioactive nanofibrous scaffolds, injectable scaffolds and stem cells, and pre-clinical findings using stem-cell-based strategies. These topics are discussed in detail in an attempt to provide future direction and to shed light on

Introducing regenerative design and circularity into architectural and engineering curriculum

OpenAIRE

Attia, Shady

2016-01-01

Looking today to the challenges for planning and design of sustainable built environment including, carbon emissions, climate change, human health, water problems, biodiversity, scarcity of resources, depletion of fossil fuel, population growth and urbanization; sustainable architecture will play a key role for the sustainable development of society as a whole. In the context of an architectural design studio, this paper presents the experience of introducing the concept of regenerative desig...

Oxygen consumption and cytochrome exidase activity of axolotl limbs muscle tissue in restoration of regenerative ability suprressed by X-irradiation

International Nuclear Information System (INIS)

Teplits, N.A.

1975-01-01

The rate of oxygen use and activity of cytochrome oxidase in a homogenate of mitochondria and nuclei of muscle tissue of axolotl limbs after suppression of their regenerative capability by x irradiation and their restoration was studied experimentally. With suppression of the regenative capability the use of oxygen was depressed. Cytochrome oxidase activity in the homogenate and mitochondria decreased compared to that of the intact limb, in the nuclei of muscle tissue it was the same or greater. With restoration of the regenerative capability of the limbs the respiration rate of the homogenate and the mitochondria increased, accompanied by increased cytochrome oxidase activity. In the nuclei the cytochrome oxidase activity did not change in the blastema stage and sharply decreased in the limb formation state. (E.T.)

Oxygen consumption and cytochrome exidase activity of axolotl limbs muscle tissue in restoration of regenerative ability suppressed by X-irradiation

Energy Technology Data Exchange (ETDEWEB)

Teplits, N A [AN SSSR, Moscow. Inst. Biologii Razvitiya

1975-01-01

The rate of oxygen use and activity of cytochrome oxidase in a homogenate of mitochondria and nuclei of muscle tissue of axolotl limbs after suppression of their regenerative capability by x irradiation and their restoration was studied experimentally. With suppression of the regenative capability the use of oxygen was depressed. Cytochrome oxidase activity in the homogenate and mitochondria decreased compared to that of the intact limb, in the nuclei of muscle tissue it was the same or greater. With restoration of the regenerative capability of the limbs the respiration rate of the homogenate and the mitochondria increased, accompanied by increased cytochrome oxidase activity. In the nuclei the cytochrome oxidase activity did not change in the blastema stage and sharply decreased in the limb formation state.

Free radical scavenging injectable hydrogels for regenerative therapy.

Science.gov (United States)

Komeri, Remya; Thankam, Finosh Gnanaprakasam; Muthu, Jayabalan

2017-02-01

Pathological free radicals generated from inflamed and infarcted cardiac tissues interferes natural tissue repair mechanisms. Hypoxic microenvironment at the injured zone of non-regenerating cardiac tissues hinders the therapeutic attempts including cell therapy. Here we report an injectable, cytocompatible, free radical scavenging synthetic hydrogel formulation for regenerative therapy. New hydrogel (PEAX-P) is prepared with D-xylitol-co-fumarate-co-poly ethylene adipate-co-PEG comaromer (PEAX) and PEGDiacrylate. PEAX-P hydrogel swells 4.9 times the initial weight and retains 100.07kPa Young modulus at equilibrium swelling, which is suitable for cardiac applications. PEAX-P hydrogel retains elastic nature even at 60% compressive strain, which is favorable to fit with the dynamic and elastic natural tissue counterparts. PEAX-P hydrogel scavenges 51% DPPH radical, 40% hydroxyl radicals 41% nitrate radicals with 31% reducing power. The presence of hydrogel protects 62% cardiomyoblast cells treated with stress inducing media at LD 50 concentration. The free hydroxyl groups in sugar alcohols of the comacromer influence the free radical scavenging. Comparatively, PEAX-P hydrogel based on xylitol evinces slightly lower scavenging characteristics than with previously reported PEAM-P hydrogel containing mannitol having more hydroxyl groups. The possible free radical scavenging mechanism of the present hydrogel relies on the free π electrons associated with uncrosslinked fumarate bonds, hydrogen atoms associated with sugar alcohols/PEG and radical dilution by free water in the matrix. Briefly, the present PEAX-P hydrogel is a potential injectable system for combined antioxidant and regenerative therapy. Copyright © 2016 Elsevier B.V. All rights reserved.

Concise Review: Multifaceted Characterization of Human Mesenchymal Stem Cells for Use in Regenerative Medicine

Science.gov (United States)

Samsonraj, Rebekah M.; Raghunath, Michael; Nurcombe, Victor; Hui, James H.

2017-01-01

Abstract Mesenchymal stem cells (MSC) hold great potential for regenerative medicine because of their ability for self‐renewal and differentiation into tissue‐specific cells such as osteoblasts, chondrocytes, and adipocytes. MSCs orchestrate tissue development, maintenance and repair, and are useful for musculoskeletal regenerative therapies to treat age‐related orthopedic degenerative diseases and other clinical conditions. Importantly, MSCs produce secretory factors that play critical roles in tissue repair that support both engraftment and trophic functions (autocrine and paracrine). The development of uniform protocols for both preparation and characterization of MSCs, including standardized functional assays for evaluation of their biological potential, are critical factors contributing to their clinical utility. Quality control and release criteria for MSCs should include cell surface markers, differentiation potential, and other essential cell parameters. For example, cell surface marker profiles (surfactome), bone‐forming capacities in ectopic and orthotopic models, as well as cell size and granularity, telomere length, senescence status, trophic factor secretion (secretome), and immunomodulation, should be thoroughly assessed to predict MSC utility for regenerative medicine. We propose that these and other functionalities of MSCs should be characterized prior to use in clinical applications as part of comprehensive and uniform guidelines and release criteria for their clinical‐grade production to achieve predictably favorable treatment outcomes for stem cell therapy. Stem Cells Translational Medicine 2017;6:2173–2185 PMID:29076267

Energy-Regenerative Braking Control of Electric Vehicles Using Three-Phase Brushless Direct-Current Motors

Directory of Open Access Journals (Sweden)

Bo Long

2013-12-01

Full Text Available Regenerative braking provides an effective way of extending the driving range of battery powered electric vehicles (EVs. This paper analyzes the equivalent power circuit and operation principles of an EV using regenerative braking control technology. During the braking period, the switching sequence of the power converter is controlled to inverse the output torque of the three-phase brushless direct-current (DC motor, so that the braking energy can be returned to the battery. Compared with the presented methods, this technology can achieve several goals: energy recovery, electric braking, ultra-quiet braking and extending the driving range. Merits and drawbacks of different braking control strategy are further elaborated. State-space model of the EVs under energy-regenerative braking operation is established, considering that parameter variations are unavoidable due to temperature change, measured error, un-modeled dynamics, external disturbance and time-varying system parameters, a sliding mode robust controller (SMRC is designed and implemented. Phase current and DC-link voltage are selected as the state variables, respectively. The corresponding control law is also provided. The proposed control scheme is compared with a conventional proportional-integral (PI controller. A laboratory EV for experiment is setup to verify the proposed scheme. Experimental results show that the drive range of EVs can be improved about 17% using the proposed controller with energy-regeneration control.

回热型双活塞太阳能水泵的设计与研究%Design and Research of Regenerative Double Piston Solar Water Pump

Institute of Scientific and Technical Information of China (English)

崔丹丹; 郑宏飞; 毛巨正; 伍纲

2017-01-01

设计制作了一种利用太阳能或其他余热驱动的回热型双活塞水泵.通过对其建立数学模型,对其循环过程进行理论分析并给出了泵水效率.在理论分析的基础上,搭建实验系统,对其进行了性能测试,得到活塞内部工质的温度和压力变化规律以及泵水速率随加热温度和泵水高度的变化情况.由于本系统采用了双活塞并回收了部分余热,可连续泵水,95℃加热条件下,系统的泵水速率为265 kg/h.结果显示,实验与理论结果有相同的变化趋势,提高加热温度可提升装置的泵水速率和缩短循环时间,有利于提高系统的效率;提高泵水高度将会使泵水速率降低.因此该类型的小型太阳能泵水装置,泵水高度不宜设置过高.%A regenerative double piston pump driven by solar energy or other waste heat is designed and manufactured.Through the mathematical model,the circulation process is analyzed theoretically and the pump water efficiency is given.On the basis of theoretical analysis,the experimental system is built and the performance of the system is tested.The temperature and pressure variation law of the working fluid inside the piston and the variation of pump water rate with the different heating temperatures and pump water heights are obtained.As the system uses double piston and recovered some residual heat,it can continuously pump water and pump water rate of the experimental system reached 265 kg/h at 95℃ heating temperature.The results show that the experimental results agree with the theoretical results.Increasing the heating temperature can improve the pump water rate and shorten the cycle time,which is beneficial to improve the efficiency of the whole system.Meanwhile,increasing pump water height will reduce pump water rate.Therefore,for the type of small solar pump water device,pump water height should not be set too high.

The modern instrumentation used for monitoring and controlling the main parameters of the regenerative electro-mechano-hydraulic drive systems

Science.gov (United States)

Cristescu, Corneliu; Drumea, Petrin; Krevey, Petrica

2009-01-01

In this work is presented the modern instrumentation used for monitoring and controlling the main parameters for one regenerative drive system, used to recovering the kinetic energy of motor vehicles, lost in the braking phase, storing and using this energy in the starting or accelerating phases. Is presented a Romanian technical solution for a regenerative driving system, based on a hybrid solution containing a hydro-mechanic module and an existing thermal motor drive, all conceived as a mechatronics system. In order to monitoring and controlling the evolution of the main parameters, the system contains a series of sensors and transducers that provide the moment, rotation, temperature, flow and pressure values. The main sensors and transducers of the regenerative drive system, their principal features and tehnical conecting solutions are presented in this paper, both with the menaging electronic and informational subsystems.

Modeling of a regenerative indirect evaporative cooler for a desiccant cooling system

DEFF Research Database (Denmark)

Bellemo, Lorenzo; Elmegaard, Brian; Reinholdt, Lars O.

This paper presents a numerical study of a regenerative indirect evaporative cooler, the so-called Dew Point Cooler (DPC), which is part of a Desiccant Cooling system that may both dehumidify and cool humid air. The DPC model is based on first principles using a 1D finite volume scheme...

Induced pluripotent stem cells and their implication for regenerative medicine.

Science.gov (United States)

Csobonyeiova, Maria; Polak, Stefan; Koller, Jan; Danisovic, Lubos

2015-06-01

In 2006 Yamanaka's group showed that stem cells with properties similar to embryonic stem cells could be generated from mouse fibroblasts by introducing four genes. These cells were termed induced pluripotent stem cells (iPSCs). Because iPSCs avoid many of ethical concerns associated with the use of embryonic material, they have great potential in cell-based regenerative medicine. They are suitable also for other various purposes, including disease modelling, personalized cell therapy, drug or toxicity screening and basic research. Moreover, in the future, there might become possible to generate organs for human transplantation. Despite these progresses, several studies have raised the concern for genetic and epigenetic abnormalities of iPSCs that could contribute to immunogenicity of some cells differentiated from iPSCs. Recent methodological improvements are increasing the ease and efficacy of reprogramming, and reducing the genomic modification. However, to minimize or eliminate genetic alternations in the derived iPSC line creation, factor-free human iPSCs are necessary. In this review we discuss recent possibilities of using iPSCs for clinical applications and new advances in field of their reprogramming methods. The main goal of present article was to review the current knowledge about iPSCs and to discuss their potential for regenerative medicine.

Application of human amniotic mesenchymal cells as an allogeneic transplantation cell source in bone regenerative therapy

Energy Technology Data Exchange (ETDEWEB)

Tsuno, Hiroaki [Department of Regenerative Medicine, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan); Department of Oral and Maxillofacial Surgery, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan); Yoshida, Toshiko [Department of Regenerative Medicine, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan); Nogami, Makiko [Department of Regenerative Medicine, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan); Department of Orthopedic Surgery, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan); Koike, Chika; Okabe, Motonori [Department of Regenerative Medicine, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan); Noto, Zenko [Department of Regenerative Medicine, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan); Department of Oral and Maxillofacial Surgery, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan); Arai, Naoya; Noguchi, Makoto [Department of Oral and Maxillofacial Surgery, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan); Nikaido, Toshio, E-mail: tnikaido@med.u-toyama.ac.jp [Department of Regenerative Medicine, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, 2630 Sugitani Toyama, Toyama 930-0194 (Japan)

2012-12-01

Autogenous mesenchymal stem cells (MSCs) have therapeutic applications in bone regenerative therapy due to their pluripotency. However, the ability of MSCs to proliferate and differentiate varies between donors. Furthermore, alternative sources of MSCs are required for patients with contraindications to autogenous cell therapy. The aim of this study was to evaluate the potential of mesenchymal cells from the human amniotic membrane (HAM) as a source of cells for allogeneic transplantation in bone regenerative therapy. Cells that retained a proliferative capacity of more than 50 population doubling level were distinguished from other HAM cells as HAM{alpha} cells and induced to osteogenic status-their in vivo osteogenesis was subsequently investigated in rats. It was found that HAM{alpha} cells were spindle shaped and were positive for MSC markers and negative for hematopoietic stem cell markers. Alkaline phosphatase activity and calcium deposition increased with osteogenic status of HAM{alpha} cells. The expression of osteocalcin mRNA was increased in HAM{alpha} cells cultured on calcium phosphate scaffolds. Moreover, xenografted HAM{alpha} cells remained viable and produced extracellular matrix for several weeks. Thus, this study suggests that human amniotic mesenchymal cells possess osteogenic differentiation potential and could be applied to allogeneic transplantation in bone regenerative therapy. - Highlights: Black-Right-Pointing-Pointer Human amniotic mesenchymal cells include cells (HAM{alpha} cells) that have the properties of MSCs. Black-Right-Pointing-Pointer HAM{alpha} cells have excellent osteogenic differentiation potential. Black-Right-Pointing-Pointer Osteogenic differentiation ability of HAM{alpha} was amplified by calcium phosphate scaffolds. Black-Right-Pointing-Pointer HAM{alpha} cells can be applicable to allogeneic cell transplantation in bone regenerative therapy.

Clay nanoparticles for regenerative medicine and biomaterial design: A review of clay bioactivity.

Science.gov (United States)

Mousa, Mohamed; Evans, Nicholas D; Oreffo, Richard O C; Dawson, Jonathan I

2018-03-01

Clay nanoparticles, composites and hydrogels are emerging as a new class of biomaterial with exciting potential for tissue engineering and regenerative medicine applications. Clay particles have been extensively explored in polymeric nanocomposites for self-assembly and enhanced mechanical properties as well as for their potential as drug delivery modifiers. In recent years, a cluster of studies have explored cellular interactions with clay nanoparticles alone or in combination with polymeric matrices. These pioneering studies have suggested new and unforeseen utility for certain clays as bioactive additives able to enhance cellular functions including adhesion, proliferation and differentiation, most notably for osteogenesis. This review examines the recent literature describing the potential effects of clay-based nanomaterials on cell function and examines the potential role of key clay physicochemical properties in influencing such interactions and their exciting possibilities for regenerative medicine. Copyright © 2018 Elsevier Ltd. All rights reserved.

The Regenerative Potential of Parietal Epithelial Cells in Adult Mice

OpenAIRE

Berger, Katja; Schulte, Kevin; Boor, Peter; Kuppe, Christoph; van Kuppevelt, Toin H.; Floege, Jürgen; Smeets, Bart; Moeller, Marcus J.

2014-01-01

Previously, we showed that some podocytes in juvenile mice are recruited from cells lining Bowman’s capsule, suggesting that parietal epithelial cells (PECs) are a progenitor cell population for podocytes. To investigate whether PECs also replenish podocytes in adult mice, PECs were genetically labeled in an irreversible fashion in 5-week-old mice. No significant increase in labeled podocytes was observed, even after 18 months. To accelerate a potential regenerative mechanism, progressive glo...

Exergy analysis for combined regenerative Brayton and inverse Brayton cycles

OpenAIRE

Zelong Zhang, Lingen Chen, Fengrui Sun

2012-01-01

This paper presents the study of exergy analysis of combined regenerative Brayton and inverse Brayton cycles. The analytical formulae of exergy loss and exergy efficiency are derived. The largest exergy loss location is determined. By taking the maximum exergy efficiency as the objective, the choice of bottom cycle pressure ratio is optimized by detailed numerical examples, and the corresponding optimal exergy efficiency is obtained. The influences of various parameters on the exergy efficien...

Regenerative Endodontic Treatment with Orthodontic Treatment in a Tooth with Dens Evaginatus: A Case Report with a 4-year Follow-up.

Science.gov (United States)

Natera, Marianella; Mukherjee, Padma M

2018-06-01

Dens evaginatus is a developmental tooth anomaly in which an extra cusp or tubercle protrudes on the occlusal surface of the tooth along with some pulpal tissue. Because of the fragile nature of the protrusion, these teeth are often at risk of pulpal exposure. When this occurs in an immature tooth, regenerative endodontic treatment may be a good treatment approach to promote root formation. There is limited literature that documents the occurrence of orthodontic treatment in teeth that have undergone regenerative endodontic therapy using triple antibiotic paste. Here we present a case of an immature premolar tooth with dens evaginatus that was diagnosed with pulp necrosis and chronic apical abscess. The tooth was treated with regenerative endodontic treatment; after which, the patient received orthodontic treatment with fixed appliances for 2 years. The tooth responded favorably to the regenerative endodontic treatment and orthodontic tooth movement. Clinically and radiographically, all the follow-up examinations revealed an asymptomatic tooth with evidence of periapical healing with stunted root development. The tooth remained asymptomatic even after 4 years. The regenerative endodontic procedure (REP) was successful in treating an immature permanent premolar with pulp necrosis and apical periodontitis with dens evaginatus. In this case, the tooth treated with an REP responded to orthodontic treatment similar to the nonendodontically treated teeth. Further studies are recommended to clarify the precise effects of orthodontic treatment on teeth treated with an REP. Copyright © 2018 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Dental Mesenchymal Stem Cell-Based Translational Regenerative Dentistry: From Artificial to Biological Replacement

Science.gov (United States)

Marei, Mona K.; El Backly, Rania M.

2018-01-01

Dentistry is a continuously changing field that has witnessed much advancement in the past century. Prosthodontics is that branch of dentistry that deals with replacing missing teeth using either fixed or removable appliances in an attempt to simulate natural tooth function. Although such “replacement therapies” appear to be easy and economic they fall short of ever coming close to their natural counterparts. Complications that arise often lead to failures and frequent repairs of such devices which seldom allow true physiological function of dental and oral-maxillofacial tissues. Such factors can critically affect the quality of life of an individual. The market for dental implants is continuously growing with huge economic revenues. Unfortunately, such treatments are again associated with frequent problems such as peri-implantitis resulting in an eventual loss or replacement of implants. This is particularly influential for patients having co-morbid diseases such as diabetes or osteoporosis and in association with smoking and other conditions that undoubtedly affect the final treatment outcome. The advent of tissue engineering and regenerative medicine therapies along with the enormous strides taken in their associated interdisciplinary fields such as stem cell therapy, biomaterial development, and others may open arenas to enhancing tissue regeneration via designing and construction of patient-specific biological and/or biomimetic substitutes. This review will overview current strategies in regenerative dentistry while overviewing key roles of dental mesenchymal stem cells particularly those of the dental pulp, until paving the way to precision/translational regenerative medicine therapies for future clinical use. PMID:29770323

Dental Mesenchymal Stem Cell-Based Translational Regenerative Dentistry: From Artificial to Biological Replacement

Directory of Open Access Journals (Sweden)

Mona K. Marei

2018-05-01

Full Text Available Dentistry is a continuously changing field that has witnessed much advancement in the past century. Prosthodontics is that branch of dentistry that deals with replacing missing teeth using either fixed or removable appliances in an attempt to simulate natural tooth function. Although such “replacement therapies” appear to be easy and economic they fall short of ever coming close to their natural counterparts. Complications that arise often lead to failures and frequent repairs of such devices which seldom allow true physiological function of dental and oral-maxillofacial tissues. Such factors can critically affect the quality of life of an individual. The market for dental implants is continuously growing with huge economic revenues. Unfortunately, such treatments are again associated with frequent problems such as peri-implantitis resulting in an eventual loss or replacement of implants. This is particularly influential for patients having co-morbid diseases such as diabetes or osteoporosis and in association with smoking and other conditions that undoubtedly affect the final treatment outcome. The advent of tissue engineering and regenerative medicine therapies along with the enormous strides taken in their associated interdisciplinary fields such as stem cell therapy, biomaterial development, and others may open arenas to enhancing tissue regeneration via designing and construction of patient-specific biological and/or biomimetic substitutes. This review will overview current strategies in regenerative dentistry while overviewing key roles of dental mesenchymal stem cells particularly those of the dental pulp, until paving the way to precision/translational regenerative medicine therapies for future clinical use.

Thermodynamic analysis of the heat regenerative cycle in porous medium engine

International Nuclear Information System (INIS)

Liu Hongsheng; Xie Maozhao; Wu Dan

2009-01-01

The advantages of homogeneous combustion in internal combustion engines are well known all over the world. Recent years, porous medium (PM) engine has been proposed as a new type engine based on the technique of combustion in porous medium, which can fulfils all requirements to perform homogeneous combustion. In this paper, working processes of a PM engine are briefly introduced and an ideal thermodynamic model of the PM heat regeneration cycle in PM engine is developed. An expression for the relation between net work output and thermal efficiency is derived for the cycle. In order to evaluate of the cycle, the influences of the expansion ratio, initial temperature and limited temperature on the net work and efficiency are discussed, and the availability terms of the cycle are analyzed. Comparing the PM heat regenerative cycle of the PM engine against Otto cycle and Diesel cycle shows that PM heat regenerative cycle can improve net work output greatly with little drop of efficiency. The aim of this paper is to predict the thermodynamic performance of PM heat regeneration cycle and provide a guide to further investigations of the PM engine

Ocular progenitor cells and current applications in regenerative medicines – Review

Directory of Open Access Journals (Sweden)

K. Gokuladhas

2017-06-01

Full Text Available The recent emerging field of regenerative medicine is to present solutions for chronic diseases which cannot be sufficiently repaired by the body's own mechanisms. Stem cells are undifferentiated biological cells and have the potential to develop into many different cell types in the body during early life and growth. Self renewal and totipotency are the characteristic features of stem cells and it holds a promising result for treating various diseases like diabetic foot ulcer, heart diseases, lung diseases, Autism, Skin diseases, arthritis including eye disease. Failure of complete recovery of eye diseases and complications that follow conventional treatments have shifted search to a new form of regenerative medicine using Stem cells. The ocular progenitor cells are remarkable in stem cell biology and replenishing degenerated cells despite being present in low quantity and quiescence in our body has a high therapeutic value. In this paper we have review the applications on ocular progenitor stem cells in treatment of human eye diseases and address the strategies that have been exploited in an effort to regain visual function in the advance treatment of stem cells without any side effects and also present the significance in advance stem cell research.

Cardiovascular disease: primary prevention, disease modulation and regenerative therapy.

LENUS (Irish Health Repository)

Sultan, Sherif

2012-10-01

Cardiovascular primary prevention and regeneration programs are the contemporary frontiers in functional metabolic vascular medicine. This novel science perspective harnesses our inherent ability to modulate the interface between specialized gene receptors and bioavailable nutrients in what is labeled as the nutrient-gene interaction. By mimicking a natural process through the conveyance of highly absorbable receptor specific nutrients, it is feasible to accelerate cell repair and optimize mitochondrial function, thereby achieving cardiovascular cure. We performed a comprehensive review of PubMed, EMBASE and Cochrane Review databases for articles relating to cardiovascular regenerative medicine, nutrigenomics and primary prevention, with the aim of harmonizing their roles within contemporary clinical practice. We searched in particular for large-scale randomized controlled trials on contemporary cardiovascular pharmacotherapies and their specific adverse effects on metabolic pathways which feature prominently in cardiovascular regenerative programs, such as nitric oxide and glucose metabolism. Scientific research on \\'cardiovascular-free\\' centenarians delineated that low sugar and low insulin are consistent findings. As we age, our insulin level increases. Those who can decelerate the rapidity of this process are prompting their cardiovascular rejuvenation. It is beginning to dawn on some clinicians that contemporary treatments are not only failing to impact on our most prevalent diseases, but they may be causing more damage than good. Primary prevention programs are crucial elements for a better outcome. Cardiovascular primary prevention and regeneration programs have enhanced clinical efficacy and quality of life and complement our conventional endovascular practice.

Application of Stem Cell Technology in Dental Regenerative Medicine.

Science.gov (United States)

Feng, Ruoxue; Lengner, Chistopher

2013-07-01

In this review, we summarize the current literature regarding the isolation and characterization of dental tissue-derived stem cells and address the potential of these cell types for use in regenerative cell transplantation therapy. Looking forward, platforms for the delivery of stem cells via scaffolds and the use of growth factors and cytokines for enhancing dental stem cell self-renewal and differentiation are discussed. We aim to understand the developmental origins of dental tissues in an effort to elucidate the molecular pathways governing the genesis of somatic dental stem cells. The advantages and disadvantages of several dental stem cells are discussed, including the developmental stage and specific locations from which these cells can be purified. In particular, stem cells from human exfoliated deciduous teeth may act as a very practical and easily accessibly reservoir for autologous stem cells and hold the most value in stem cell therapy. Dental pulp stem cells and periodontal ligament stem cells should also be considered for their triple lineage differentiation ability and relative ease of isolation. Further, we address the potentials and limitations of induced pluripotent stem cells as a cell source in dental regenerative. From an economical and a practical standpoint, dental stem cell therapy would be most easily applied in the prevention of periodontal ligament detachment and bone atrophy, as well as in the regeneration of dentin-pulp complex. In contrast, cell-based tooth replacement due to decay or other oral pathology seems, at the current time, an untenable approach.

Personalized Regenerative Medicine

Directory of Open Access Journals (Sweden)

Babak Arjmand

2017-03-01

Full Text Available Personalized medicine as a novel field of medicine refers to the prescription of specific therapeutics procedure for an individual. This approach has established based on pharmacogenetic and pharmacogenomic information and data. The terms precision and personalized medicines are sometimes applied interchangeably. However, there has been a shift from “personalized medicine” towards “precision medicine”. Although personalized medicine emerged from pharmacogenetics, nowadays it covers many fields of healthcare. Accordingly, regenerative medicine and cellular therapy as the new fields of medicine use cell-based products in order to develop personalized treatments. Different sources of stem cells including mesenchymal stem cells, embryonic stem cells and induced pluripotent stem cells (iPSCs have been considered in targeted therapies which could give many advantages. iPSCs as the novel and individual pluripotent stem cells have been introduced as the appropriate candidates for personalized cell therapies. Cellular therapies can provide a personalized approach. Because of person-to-person and population differences in the result of stem cell therapy, individualized cellular therapy must be adjusted according to the patient specific profile, in order to achieve best therapeutic results and outcomes. Several factors should be considered to achieve personalized stem cells therapy such as, recipient factors, donor factors, and the overall body environment in which the stem cells could be active and functional. In addition to these factors, the source of stem cells must be carefully chosen based on functional and physical criteria that lead to optimal outcomes.

Renal endogenous stem cells: a new source for regenerative medicine in preterms?

Directory of Open Access Journals (Sweden)

Gavino Faa

2015-10-01

Full Text Available The creation of new medical approaches based on stem cells to treat chronic kidney disease (CKD and in particular end stage renal disease (ESRD has become imperative in recent years, due to the significant burdens of patients affected by renal failure and to the limitations of dialysis and kidney transplantation to solve the problem. The initial prospective of utilizing stem cells for regenerating the affected kidney has been at the basis of excitement and hope for all patients affected by ESRD. Unfortunately, too many challenges have halted the possibility to make such regenerative approach a reality, and the vast majority of patients with CKD and renal insufficiency experience a reduced quality of life associated with high mortality. The problem appears particularly severe when ESDR develops in childhood. Children submitted to kidney transplantation have a 95% of survival rate at 5 years, but only 66% of them survive at 20 years after renal transplant. As a result, patients transplanted in childhood will need repeated renal transplants during their life.Renal regenerative medicine might experience a major renaissance in the next years, developing new methodologies stemmed from the previous attempts. Here, we present some major points to be addressed, in order to open a debate on the potential offered by the different regenerative methodologies:the “exogenous” approach; the “endogenous” approach; the “therapeutic” approach; the “prevention” approach. Proceedings of the 11th International Workshop on Neonatology and Satellite Meetings · Cagliari (Italy · October 26th-31st, 2015 · From the womb to the adultGuest Editors: Vassilios Fanos (Cagliari, Italy, Michele Mussap (Genoa, Italy, Antonio Del Vecchio (Bari, Italy, Bo Sun (Shanghai, China, Dorret I. Boomsma (Amsterdam, the Netherlands, Gavino Faa (Cagliari, Italy, Antonio Giordano (Philadelphia, USA

Concise Review: Multifaceted Characterization of Human Mesenchymal Stem Cells for Use in Regenerative Medicine.

Science.gov (United States)

Samsonraj, Rebekah M; Raghunath, Michael; Nurcombe, Victor; Hui, James H; van Wijnen, Andre J; Cool, Simon M

2017-12-01

Mesenchymal stem cells (MSC) hold great potential for regenerative medicine because of their ability for self-renewal and differentiation into tissue-specific cells such as osteoblasts, chondrocytes, and adipocytes. MSCs orchestrate tissue development, maintenance and repair, and are useful for musculoskeletal regenerative therapies to treat age-related orthopedic degenerative diseases and other clinical conditions. Importantly, MSCs produce secretory factors that play critical roles in tissue repair that support both engraftment and trophic functions (autocrine and paracrine). The development of uniform protocols for both preparation and characterization of MSCs, including standardized functional assays for evaluation of their biological potential, are critical factors contributing to their clinical utility. Quality control and release criteria for MSCs should include cell surface markers, differentiation potential, and other essential cell parameters. For example, cell surface marker profiles (surfactome), bone-forming capacities in ectopic and orthotopic models, as well as cell size and granularity, telomere length, senescence status, trophic factor secretion (secretome), and immunomodulation, should be thoroughly assessed to predict MSC utility for regenerative medicine. We propose that these and other functionalities of MSCs should be characterized prior to use in clinical applications as part of comprehensive and uniform guidelines and release criteria for their clinical-grade production to achieve predictably favorable treatment outcomes for stem cell therapy. Stem Cells Translational Medicine 2017;6:2173-2185. © 2017 The Authors Stem Cells Translational Medicine published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

Histologic Outcomes of Uninfected Human Immature Teeth Treated with Regenerative Endodontics: 2 Case Reports.

Science.gov (United States)

Nosrat, Ali; Kolahdouzan, Alireza; Hosseini, Farzaneh; Mehrizi, Ehsan A; Verma, Prashant; Torabinejad, Mahmoud

2015-10-01

A growing body of evidence exists showing the possibility of growing vital tissues in the root canal spaces of teeth with necrotic pulps and open apices. However, there is very limited histologic information regarding characteristics of tissues formed in the root canal space of human teeth after regenerative endodontics. The aim of this study was to examine clinically and histologically the outcomes of human immature teeth treated with regenerative endodontics. Two healthy birooted human maxillary first premolar teeth scheduled for extraction were included. Preoperative radiographs confirmed that these teeth had immature apices. Vitality tests showed the presence of vital pulps in these teeth. After receiving consent forms, the teeth were isolated with a rubber dam, and the pulps were completely removed. After the formation of blood clots in the canals, the teeth were covered with mineral trioxide aggregate. Four months later, the teeth were clinically and radiographically evaluated, extracted, and examined histologically. Both patients remained asymptomatic after treatment. Radiographic examination of the teeth showed signs of root development after treatment. Histologic examination of tissues growing into the root canal space of these teeth shows the presence of connective tissue, bone and cementum formation, and thickening of roots. Based on our findings, it appears that when canals of teeth with open apices are treated with regenerative endodontics, tissues of the periodontium grow into the root canals of these teeth. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Medicina regenerativa y superficie ocular Regenerative medicine and ocular surface

Directory of Open Access Journals (Sweden)

Taimi Cárdenas Díaz

2012-06-01

Full Text Available En los últimos años se ha producido un extraordinario avance en los conocimientos relacionados con diferentes ramas biomédicas, entre ellas, la biología celular. Esto ha dado un notable impulso a una nueva rama de la medicina denominada medicina regenerativa. Esta nueva disciplina médica se basa fundamentalmente en los nuevos conocimientos sobre las células madre y en su capacidad de convertirse en células de diferentes tejidos. Una de las estructuras que tiene más interés, desde el punto de vista de la medicina regenerativa, es la superficie ocular. Por esto, se ha logrado notables progresos en la reconstrucción de la superficie ocular mediante la aplicación de procederes regenerativos. Los cultivos de células del epitelio corneal humano están siendo utilizados en el tratamiento de la insuficiencia limbar. Esto permite disminuir la incidencia de opacidades tipo Haze tras queratectomía fotorrefractiva, acelerar la curación y evitar la aparición de leucomas en pacientes con defectos epiteliares persistentes e intentar disminuir la incidencia de opacidades corneales en pacientes sometidos a queratectomía fototerapéutica por diferentes distrofias corneales.In the last few years, an extraordinary advance has taken place in the knowledge about several biomedical branches as is the case of cellular biology, which has remarkably encouraged the development of a new medical branch called regenerative medicine. This medical discipline is fundamentally based on the new knowledge on the stem cells and their capacity to become cells for different tissues. One of the most interesting structures for the regenerative medicine is the ocular surface. In the last few years, significant advances have been achieved in the field of the ocular surface reconstruction with regenerative procedures. Some cell cultures of the human corneal epithelium are being used to treat limber insufficiency, to reduce the incidence of haze-type opacities after

Solar Power System Evaluated for the Human Exploration of Mars

Science.gov (United States)

Kerslake, Thomas W.

2000-01-01

The electric power system is a crucial element of any mission for the human exploration of the Martian surface. The bulk of the power generated will be delivered to crew life support systems, extravehicular activity suits, robotic vehicles, and predeployed in situ resource utilization (ISRU) equipment. In one mission scenario, before the crew departs for Mars, the ISRU plant operates for 435 days producing liquefied methane and oxygen for ascent-stage propellants and water for crew life support. About 200 days after ISRU production is completed, the crew arrives for a 500-day surface stay. In this scenario, the power system must operate for a total of 1130 days (equivalent to 1100 Martian "sols"), providing 400 MW-hr of energy to the ISRU plant and up to 18 kW of daytime user power. A photovoltaic power-generation system with regenerative fuel cell (RFC) energy storage has been under study at the NASA Glenn Research Center at Lewis Field. The conceptual power system is dominated by the 4000- m2 class photovoltaic array that is deployed orthogonally as four tent structures, each approximately 5 m on a side and 100-m long. The structures are composed of composite members deployed by an articulating mast, an inflatable boom, or rover vehicles, and are subsequently anchored to the ground. Array panels consist of thin polymer membranes with thin-film solar cells. The array is divided into eight independent electrical sections with solar cell strings operating at 600 V. Energy storage is provided by regenerative fuel cells based on hydrogen-oxygen proton exchange membrane technology. Hydrogen and oxygen reactants are stored in gaseous form at 3000 psi, and the water produced is stored at 14.7 psi. The fuel cell operating temperature is maintained by a 40-m2 deployable pumped-fluid loop radiator that uses water as the working fluid. The power management and distribution (PMAD) architecture features eight independent, regulated 600-Vdc channels. Power management and

Comparison of Regenerative Braking Efficiencies of MY2012 and MY2013 Nissan Leaf

Directory of Open Access Journals (Sweden)

Albert Boretti

2016-07-01

Full Text Available The use of kinetic energy recovery systems (KERS is the best solution presently available to dramatically improve the energy economy of passenger cars. The paper presents an experimental analysis of the energy flow to and from the battery of a MY 2012 and a MY 2013 Nissan Leaf covering the Urban Dynamometer Driving Schedule (UDDS. The two vehicles differ for the integration of the electric drivetrain component, plus a different use of the electric motor and the regenerative brakes, in addition to a different weight. It is shown that while the efficiency propulsive power to vehicle / power from battery are basically unchanged, at about 87-89 %, the efficiency power to the battery / braking power to vehicle are significantly improved from values of about 70-80 % to values of 72-87 %. The analysis provides a state-of-the-art benchmark of the propulsion and regenerative braking efficiencies of electric vehicles.

Regenerative BBU starting currents in standing wave cavities

International Nuclear Information System (INIS)

Vetter, A.M.; Buller, T.L.

1992-01-01

An analytical method for determining regenerative beam breakup (BBU) starting current, in which the contributions of single-cell field configuration and multi-cell structure mode are separated, is described. The field configuration within each cell is determined to close approximation through the use of mesh codes, which also relate the wall losses to the voltage drop along the beam path. The cell-to-cell amplitude variation may be determined by bead pull measurements on model cavities, or by assuming idealized structure modes. As an example, the I S Q L product for TM 110 -like modes of a 433-MHz, 5-cell, slot-coupled cavity is obtained. (author). 3 figs

Institutional framework and the principles of regenerative medicine centers and rehabilitation in a megapolis

OpenAIRE

Shapovalenko Т.V.

2013-01-01

A concept of development of centers for regenerative medicine and rehabilitation, organizational bases of rehabilitation centers, basic principles and approaches to the creation and activities of the rehabilitation treatment and rehabilitation in the city are presented in the study.

A 500μW 5Mbps ULP super-regenerative RF front-end

NARCIS (Netherlands)

Vidojkovic, M.; Rampu, S.; Imamura, K.; Harpe, P.; Dolmans, G.; Groot, H. de

2010-01-01

This paper presents an ultra low power super-regenerative RF front-end for wireless body area network (WBAN) applications. The RF front-end operates in the 2.36-2.4 GHz medical BAN and 2.4-2.485 GHz ISM bands, and consumes 500 μW. It supports OOK modulation at high data rates ranging from 1-5 Mbps.

Regenerative raw materials - High technology without end; Nachwachsende Rohstoffe - Spitzentechnologie ohne Ende

Energy Technology Data Exchange (ETDEWEB)

Wenig, Barbara

2007-07-01

Regenerative raw materials are the basis for a multiplicity of environmentally friendly products. Regenerating raw materials fascinate by special qualities and offer the possibility of preserving only restricted existing fossil resources and climatic friendly managing. The review under consideration reports on areas in which vegetable raw materials already are established as well as on future prospects.

Temporomandibular Joint Regenerative Medicine

Directory of Open Access Journals (Sweden)

Xavier Van Bellinghen

2018-02-01

Full Text Available The temporomandibular joint (TMJ is an articulation formed between the temporal bone and the mandibular condyle which is commonly affected. These affections are often so painful during fundamental oral activities that patients have lower quality of life. Limitations of therapeutics for severe TMJ diseases have led to increased interest in regenerative strategies combining stem cells, implantable scaffolds and well-targeting bioactive molecules. To succeed in functional and structural regeneration of TMJ is very challenging. Innovative strategies and biomaterials are absolutely crucial because TMJ can be considered as one of the most difficult tissues to regenerate due to its limited healing capacity, its unique histological and structural properties and the necessity for long-term prevention of its ossified or fibrous adhesions. The ideal approach for TMJ regeneration is a unique scaffold functionalized with an osteochondral molecular gradient containing a single stem cell population able to undergo osteogenic and chondrogenic differentiation such as BMSCs, ADSCs or DPSCs. The key for this complex regeneration is the functionalization with active molecules such as IGF-1, TGF-β1 or bFGF. This regeneration can be optimized by nano/micro-assisted functionalization and by spatiotemporal drug delivery systems orchestrating the 3D formation of TMJ tissues.

Regenerative hair waves in aging mice and extra-follicular modulators follistatin, dkk1, and sfrp4.

Science.gov (United States)

Chen, Chih-Chiang; Murray, Philip J; Jiang, Ting Xin; Plikus, Maksim V; Chang, Yun-Ting; Lee, Oscar K; Widelitz, Randall B; Chuong, Cheng-Ming

2014-08-01

Hair cycling is modulated by factors both intrinsic and extrinsic to hair follicles. Cycling defects lead to conditions such as aging-associated alopecia. Recently, we demonstrated that mouse skin exhibits regenerative hair waves, reflecting a coordinated regenerative behavior in follicle populations. Here, we use this model to explore the regenerative behavior of aging mouse skin. Old mice (>18 months) tracked over several months show that with progressing age, hair waves slow down, wave propagation becomes restricted, and hair cycle domains fragment into smaller domains. Transplanting aged donor mouse skin to a young host can restore donor cycling within a 3 mm range of the interface, suggesting that changes are due to extracellular factors. Therefore, hair stem cells in aged skin can be reactivated. Molecular studies show that extra-follicular modulators Bmp2, Dkk1, and Sfrp4 increase in early anagen. Further, we identify follistatin as an extra-follicular modulator, which is highly expressed in late telogen and early anagen. Indeed, follistatin induces hair wave propagation and its level decreases in aging mice. We present an excitable medium model to simulate the cycling behavior in aging mice and illustrate how the interorgan macroenvironment can regulate the aging process by integrating both "activator" and "inhibitor" signals.

Heterogeneity among muscle precursor cells in adult skeletal muscles with differing regenerative capacities.

Science.gov (United States)

Pavlath, G K; Thaloor, D; Rando, T A; Cheong, M; English, A W; Zheng, B

1998-08-01

Skeletal muscle has a remarkable capacity to regenerate after injury, although studies of muscle regeneration have heretofore been limited almost exclusively to limb musculature. Muscle precursor cells in skeletal muscle are responsible for the repair of damaged muscle. Heterogeneity exists in the growth and differentiation properties of muscle precursor cell (myoblast) populations throughout limb development but whether the muscle precursor cells differ among adult skeletal muscles is unknown. Such heterogeneity among myoblasts in the adult may give rise to skeletal muscles with different regenerative capacities. Here we compare the regenerative response of a masticatory muscle, the masseter, to that of limb muscles. After exogenous trauma (freeze or crush injuries), masseter muscle regenerated much less effectively than limb muscle. In limb muscle, normal architecture was restored 12 days after injury, whereas in masseter muscle, minimal regeneration occurred during the same time period. Indeed, at late time points, masseter muscles exhibited increased fibrous connective tissue in the region of damage, evidence of ineffective muscle regeneration. Similarly, in response to endogenous muscle injury due to a muscular dystrophy, widespread evidence of impaired regeneration was present in masseter muscle but not in limb muscle. To explore the cellular basis of these different regenerative capacities, we analyzed the myoblast populations of limb and masseter muscles both in vivo and in vitro. From in vivo analyses, the number of myoblasts in regenerating muscle was less in masseter compared with limb muscle. Assessment of population growth in vitro indicated that masseter myoblasts grow more slowly than limb myoblasts under identical conditions. We conclude that the impaired regeneration in masseter muscles is due to differences in the intrinsic myoblast populations compared to limb muscles.

Comparison of Hematopoietic and Spermatogonial Stem Cell Niches from the Regenerative Medicine Aspect.

Science.gov (United States)

Köse, Sevil; Yersal, Nilgün; Önen, Selin; Korkusuz, Petek

2018-06-08

Recent advances require a dual evaluation of germ and somatic stem cell niches with a regenerative medicine perspective. For a better point of view of the niche concept, it is needed to compare the microenvironments of those niches in respect to several components. The cellular environment of spermatogonial stem cells' niche consists of Sertoli cells, Leydig cells, vascular endothelial cells, epididymal fat cells, peritubular myoid cells while hematopoietic stem cells have mesenchymal stem cells, osteoblasts, osteoclasts, megacaryocytes, macrophages, vascular endothelial cells, pericytes and adipocytes in their microenvironment. Not only those cells', but also the effect of the other factors such as hormones, growth factors, chemokines, cytokines, extracellular matrix components, biomechanical forces (like shear stress, tension or compression) and physical environmental elements such as temperature, oxygen level and pH will be clarified during the chapter. Because it is known that the microenvironment has an important role in the stem cell homeostasis and disease conditions, it is crucial to understand the details of the microenvironment and to be able to compare the niche concepts of the different types of stem cells from each other, for the regenerative interventions. Indeed, the purpose of this chapter is to point out the usage of niche engineering within the further studies in the regenerative medicine field. Decellularized, synthetic or non-synthetic scaffolds may help to mimic the stem cell niche. However, the shared or different characteristics of germ and somatic stem cell microenvironments are necessary to constitute a proper niche model. When considered from this aspect, it is possible to produce some strategies on the personalized medicine by using those artificial models of stem cell microenvironment.

Not Missing the Future: A Call to Action for Investigating the Role of Regenerative Medicine Therapies in Pediatric/Adolescent Sports Injuries.

Science.gov (United States)

Best, Thomas M; Caplan, Arnold; Coleman, Michael; Goodrich, Laurie; Hurd, Jason; Kaplan, Lee D; Noonan, Ben; Schoettle, Philip; Scott, Christopher; Stiene, Henry; Huard, Johnny

In August 2016, a group including sport medicine clinicians, researchers, and a bioethicist met in Vail, Colorado to discuss regenerative medicine and its potential role in youth sports injuries. There was consensus that a call to action is urgently needed to understand the current evidence base, the risks and rewards, and future directions of research and clinical practice for regenerative medicine therapies in youth sports. We present here a summary of our meeting, which was supported by the National Youth Sports Health and Safety Institute (NYSHSI), a partnership between the American College of Sports Medicine (ACSM) and Sanford Health. The group's goal is to educate practitioners and the public, and to pioneer a means of accumulating meaningful clinical data on regenerative medicine therapies in pediatric and adolescent athletes.

Preventive and Regenerative Foam Rolling are Equally Effective in Reducing Fatigue-Related Impairments of Muscle Function following Exercise

Directory of Open Access Journals (Sweden)

Johannes Fleckenstein, Jan Wilke, Lutz Vogt, Winfried Banzer

2017-12-01

Full Text Available Objectives of the study were to compare the effects of a single bout of preventive or regenerative foam rolling (FR on exercise-induced neuromuscular exhaustion. Single-centre randomised-controlled study was designed. Forty-five healthy adults (22 female; 25±2 yrs were allocated to three groups: 1 FR of the lower limb muscles prior to induction of fatigue, 2 FR after induction of fatigue, 3 no-treatment control. Neuromuscular exhaustion was provoked using a standardized and validated functional agility short-term fatigue protocol. Main outcome measure was the maximal isometric voluntary force of the knee extensors (MIVF. Secondary outcomes included pain and reactive strength (RSI. Preventive (-16% and regenerative FR (-12% resulted in a decreased loss in MIVF compared to control (-21%; p 0.8, p < 0.1. Differences over time (p < 0.001 between groups regarding pain and RSI did not turn out to be clinically meaningful. A single bout of foam rolling reduces neuromuscular exhaustion with reference to maximal force production. Regenerative rather than preventive foam rolling seems sufficient to prevent further fatigue.

Smart Dressings Based on Nanostructured Fibers Containing Natural Origin Antimicrobial, Anti-Inflammatory, and Regenerative Compounds

Directory of Open Access Journals (Sweden)

Vanesa Andreu

2015-08-01

Full Text Available A fast and effective wound healing process would substantially decrease medical costs, wound care supplies, and hospitalization significantly improving the patients’ quality of life. The search for effective therapeutic approaches seems to be imperative in order to avoid the aggravation of chronic wounds. In spite of all the efforts that have been made during the recent years towards the development of artificial wound dressings, none of the currently available options combine all the requirements necessary for quick and optimal cutaneous regeneration. Therefore, technological advances in the area of temporary and permanent smart dressings for wound care are required. The development of nanoscience and nanotechnology can improve the materials and designs used in topical wound care in order to efficiently release antimicrobial, anti-inflammatory and regenerative compounds speeding up the endogenous healing process. Nanostructured dressings can overcome the limitations of the current coverings and, separately, natural origin components can also overcome the drawbacks of current antibiotics and antiseptics (mainly cytotoxicity, antibiotic resistance, and allergies. The combination of natural origin components with demonstrated antibiotic, regenerative, or anti-inflammatory properties together with nanostructured materials is a promising approach to fulfil all the requirements needed for the next generation of bioactive wound dressings. Microbially compromised wounds have been treated with different essential oils, honey, cationic peptides, aloe vera, plant extracts, and other natural origin occurring antimicrobial, anti-inflammatory, and regenerative components but the available evidence is limited and insufficient to be able to draw reliable conclusions and to extrapolate those findings to the clinical practice. The evidence and some promising preliminary results indicate that future comparative studies are justified but instead of talking about

Regenerative medicine and responsible research and innovation: proposals for a responsible acceleration to the clinic.

Science.gov (United States)

Webster, Andrew

2017-10-01

This paper asks how regenerative medicine can be examined through the 'responsible research and innovation' (RRI) approach which has been developed over the past decade. It describes the drivers to the development of RRI, and then argues for the need to understand innovation itself through drawing on social science analysis rooted in science and technology studies. The paper then identifies a number of highly specific challenges faced by the regenerative medicine field and the implications these have for value creation. It offers a number of examples of how a combined RRI/science and technology studies perspective can identify priority areas for policy and concludes by arguing for a 'responsible acceleration', more likely to foster readiness at a time when much of the policy domain is pushing for ever-rapid access to cell therapies.

Sustainable urban rail systems: Strategies and technologies for optimal management of regenerative braking energy

International Nuclear Information System (INIS)

González-Gil, Arturo; Palacin, Roberto; Batty, Paul

2013-01-01

Highlights: • Review of principal regenerative braking strategies and technologies for urban rail. • Different energy storage technologies are assessed for use in urban rail. • Optimising timetables is a preferential measure to improve energy efficiency. • Energy storage systems improve efficiency and reliability of urban rail systems. • Reversible substations allow for a complete recovery of braking energy. - Abstract: In a society characterised by increasing rates of urbanisation and growing concerns about environmental issues like climate change, urban rail transport plays a key role in contributing to sustainable development. However, in order to retain its inherent advantages in terms of energy consumption per transport capacity and to address the rising costs of energy, important energy efficiency measures have to be implemented. Given that numerous and frequent stops are a significant characteristic of urban rail, recuperation of braking energy offers a great potential to reduce energy consumption in urban rail systems. This paper presents a comprehensive overview of the currently available strategies and technologies for recovery and management of braking energy in urban rail, covering timetable optimisation, on-board and wayside Energy Storage Systems (ESSs) and reversible substations. For each measure, an assessment of their main advantages and disadvantages is provided alongside a list of the most relevant scientific studies and demonstration projects. This study concludes that optimising timetables is a preferential measure to increase the benefits of regenerative braking in any urban rail system. Likewise, it has been observed that ESSs are a viable solution to reuse regenerative energy with voltage stabilisation and energy saving purposes. Electrochemical Double Layer Capacitors has been identified as the most suitable technology for ESSs in general, although high specific power batteries such as Li-ion may become a practical option for on

Exergy analysis for combined regenerative Brayton and inverse Brayton cycles

Energy Technology Data Exchange (ETDEWEB)

Zhang, Zelong; Chen, Lingen; Sun, Fengrui [College of Naval Architecture and Power, Naval University of Engineering, Wuhan 430033 (China)

2012-07-01

This paper presents the study of exergy analysis of combined regenerative Brayton and inverse Brayton cycles. The analytical formulae of exergy loss and exergy efficiency are derived. The largest exergy loss location is determined. By taking the maximum exergy efficiency as the objective, the choice of bottom cycle pressure ratio is optimized by detailed numerical examples, and the corresponding optimal exergy efficiency is obtained. The influences of various parameters on the exergy efficiency and other performances are analyzed by numerical calculations.

Hyperbaric oxygen therapy in a true regenerative environment, the regenerating limb of the axolotl

DEFF Research Database (Denmark)

Hansen, Kasper; Lauridsen, Henrik; Pedersen, Michael

2012-01-01

vertebrates such as the urodele amphibians (salamanders and newts), are excellent animal models for regenerative studies. The iconic Mexican axolotl (Ambystoma mexicanum) is capable of regenerating whole limbs, tail, jaw, and many inner organs, by dedifferentiation of cells to form a blastema (collection...

Regenerative nodular hyperplasia, portal vein thrombosis and primary myelofibrosis: an unusual triple association.

Science.gov (United States)

Sández Montagut, Víctor Manuel; Giráldez Gallego, Álvaro; Ontanilla Clavijo, Guilermo

2018-03-01

We report a case of a regenerative nodular hyperplasia with a portal vein cavernomatosis with a subsequent progression to symptomatic, occlusive thrombosis of the superior mesenteric vein. A thorough investigation resulted in a final diagnosis of primary myelofibrosis associated with the V617F mutation in the JAK2 gene.

Engineering cell fitness: lessons for regenerative medicine.

Science.gov (United States)

Shakiba, Nika; Zandstra, Peter W

2017-10-01

Cell competition results in the loss of weaker cells and the dominance of stronger cells. So-called 'loser' cells are either removed by active elimination or by limiting their access to survival factors. Recently, competition has been shown to serve as a surveillance mechanism against emerging aberrant cells in both the developing and adult organism, contributing to overall organism fitness and survival. Here, we explore the origins and implications of cell competition in development, tissue homeostasis, and in vitro culture. We also provide a forward look on the use of cell competition to interpret multicellular dynamics while offering a perspective on harnessing competition to engineer cells with optimized and controllable fitness characteristics for regenerative medicine applications. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Auto-regenerative thermoluminescence dating using zircon inclusions

International Nuclear Information System (INIS)

Templer, R.H.

1993-01-01

Fired ceramics containing zircon inclusions have been dated by allowing the zircons to regenerate their own thermoluminescence (TL) signal, hence auto-regenerative TL dating. The technique is conceptually straightforward. One first measures the TL accrued since the last heating of the material. The zircon grains are then stored for six months and the TL signal regenerated through self-irradiation is measured. Since the internal dose-rate for zircon is dominated by the internal component the age of the sample is simply given by the ratio of the natural to auto-regenerated signal times the laboratory storage period. The technique, however, requires the measurement of a very small auto-regenerated signal, which introduces a number of experimental and physical complications. The methods for overcoming these problems and successfully dating zircons by auto-regeneration are described. (Author)

Regenerative immunology: the immunological reaction to biomaterials.

Science.gov (United States)

Cravedi, Paolo; Farouk, Samira; Angeletti, Andrea; Edgar, Lauren; Tamburrini, Riccardo; Duisit, Jerome; Perin, Laura; Orlando, Giuseppe

2017-12-01

Regenerative medicine promises to meet two of the most urgent needs of modern organ transplantation, namely immunosuppression-free transplantation and an inexhaustible source of organs. Ideally, bioengineered organs would be manufactured from a patient's own biomaterials-both cells and the supporting scaffolding materials in which cells would be embedded and allowed to mature to eventually regenerate the organ in question. While some groups are focusing on the feasibility of this approach, few are focusing on the immunogenicity of the scaffolds that are being developed for organ bioengineering purposes. This review will succinctly discuss progress in the understanding of immunological characteristics and behavior of different scaffolds currently under development, with emphasis on the extracellular matrix scaffolds obtained decellularized animal or human organs which seem to provide the ideal template for bioengineering purposes. © 2017 Steunstichting ESOT.

Tissue-specific composite cell aggregates drive periodontium tissue regeneration by reconstructing a regenerative microenvironment.

Science.gov (United States)

Zhu, Bin; Liu, Wenjia; Zhang, Hao; Zhao, Xicong; Duan, Yan; Li, Dehua; Jin, Yan

2017-06-01

Periodontitis is the most common cause of periodontium destruction. Regeneration of damaged tissue is the expected treatment goal. However, the regeneration of a functional periodontal ligament (PDL) insertion remains a difficulty, due to complicated factors. Recently, periodontal ligament stem cells (PDLSCs) and bone marrow-derived mesenchymal stem cells (BMMSCs) have been shown to participate in PDL regeneration, both pathologically and physiologically. Besides, interactions affect the biofunctions of different derived cells during the regenerative process. Therefore, the purpose of this study was to discuss the different derived composite cell aggregate (CA) systems of PDLSCs and BMMSCs (iliac-derived or jaw-derived) for periodontium regeneration under regenerative microenvironment reconstruction. Our results showed although all three mono-MSC CAs were compacted and the cells arranged regularly in them, jaw-derived BMMSC (JBMMSC) CAs secreted more extracellular matrix than the others. Furthermore, PDLSC/JBMMSC compound CAs highly expressed ALP, Col-I, fibronectin, integrin-β1 and periostin, suggesting that their biofunction is more appropriate for periodontal structure regeneration. Inspiringly, PDLSC/JBMMSC compound CAs regenerated more functional PDL-like tissue insertions in both nude mice ectopic and minipig orthotopic transplantation. The results indicated that the different derived CAs of PDLSCs/JBMMSCs provided an appropriate regenerative microenvironment facilitating a more stable and regular regeneration of functional periodontium tissue. This method may provide a possible strategy to solve periodontium defects in periodontitis and powerful experimental evidence for clinical applications in the future. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

Parameters Analysis of Hydraulic-Electrical Energy Regenerative Absorber on Suspension Performance

Directory of Open Access Journals (Sweden)

Han Zhang

2014-05-01

Full Text Available To recycle the vibration energy of vehicles over rough roads, a hydraulic-electricity energy regenerative suspension (HEERS was designed in the present work, and simulations were performed with focus on its performance. On the basis of the system principle, the mathematical model of hydraulic-electrical energy regenerative absorber (HEERA and two degrees of freedom (DOF suspension dynamic model were constructed. Using the model of HEERA, simulations on force-displacement and force-velocity characteristics were performed with a 1.67 Hz frequency and a sinusoidal input adopted. And then in combination with HEERA model and two DOF suspension models, simulations on the performance of HEERS also were carried out. Finally, the influences of charging pressure and volume of the accumulator, hydraulic motor displacement, orifice area of check valve, and inner diameter of hydraulic pipelines on the performance of HEERA and HEERS were investigated in depth. The simulation results indicated that (i the damping characteristic of HEERA was coincident with the damping characteristics of traditional absorber; (ii the most remarkable influencing factor on the performance of HEERS was the hydraulic motor displacement, followed by orifice area of check valve, inner diameter of pipelines, and charging pressure of accumulator, while the effects of charging volume of accumulator were quite limited.

Planform: an application and database of graph-encoded planarian regenerative experiments.

Science.gov (United States)

Lobo, Daniel; Malone, Taylor J; Levin, Michael

2013-04-15

Understanding the mechanisms governing the regeneration capabilities of many organisms is a fundamental interest in biology and medicine. An ever-increasing number of manipulation and molecular experiments are attempting to discover a comprehensive model for regeneration, with the planarian flatworm being one of the most important model species. Despite much effort, no comprehensive, constructive, mechanistic models exist yet, and it is now clear that computational tools are needed to mine this huge dataset. However, until now, there is no database of regenerative experiments, and the current genotype-phenotype ontologies and databases are based on textual descriptions, which are not understandable by computers. To overcome these difficulties, we present here Planform (Planarian formalization), a manually curated database and software tool for planarian regenerative experiments, based on a mathematical graph formalism. The database contains more than a thousand experiments from the main publications in the planarian literature. The software tool provides the user with a graphical interface to easily interact with and mine the database. The presented system is a valuable resource for the regeneration community and, more importantly, will pave the way for the application of novel artificial intelligence tools to extract knowledge from this dataset. The database and software tool are freely available at http://planform.daniel-lobo.com.

Genetic engineering for skeletal regenerative medicine.

Science.gov (United States)

Gersbach, Charles A; Phillips, Jennifer E; García, Andrés J

2007-01-01

The clinical challenges of skeletal regenerative medicine have motivated significant advances in cellular and tissue engineering in recent years. In particular, advances in molecular biology have provided the tools necessary for the design of gene-based strategies for skeletal tissue repair. Consequently, genetic engineering has emerged as a promising method to address the need for sustained and robust cellular differentiation and extracellular matrix production. As a result, gene therapy has been established as a conventional approach to enhance cellular activities for skeletal tissue repair. Recent literature clearly demonstrates that genetic engineering is a principal factor in constructing effective methods for tissue engineering approaches to bone, cartilage, and connective tissue regeneration. This review highlights this literature, including advances in the development of efficacious gene carriers, novel cell sources, successful delivery strategies, and optimal target genes. The current status of the field and the challenges impeding the clinical realization of these approaches are also discussed.

Ionic liquids and their solid-state analogues as materials for energy generation and storage

Science.gov (United States)

Macfarlane, Douglas R.; Forsyth, Maria; Howlett, Patrick C.; Kar, Mega; Passerini, Stefano; Pringle, Jennifer M.; Ohno, Hiroyuki; Watanabe, Masayoshi; Yan, Feng; Zheng, Wenjun; Zhang, Shiguo; Zhang, Jie

2016-02-01

Salts that are liquid at room temperature, now commonly called ionic liquids, have been known for more than 100 years; however, their unique properties have only come to light in the past two decades. In this Review, we examine recent work in which the properties of ionic liquids have enabled important advances to be made in sustainable energy generation and storage. We discuss the use of ionic liquids as media for synthesis of electromaterials, for example, in the preparation of doped carbons, conducting polymers and intercalation electrode materials. Focusing on their intrinsic ionic conductivity, we examine recent reports of ionic liquids used as electrolytes in emerging high-energy-density and low-cost batteries, including Li-ion, Li-O2, Li-S, Na-ion and Al-ion batteries. Similar developments in electrolyte applications in dye-sensitized solar cells, thermo-electrochemical cells, double-layer capacitors and CO2 reduction are also discussed.

A Solar Receiver-Reactor with Specularly Reflecting Walls for High-Temperature Thermoelectrochemical and Thermochemical Processes

Science.gov (United States)

1987-10-27

on the radiosity concept1 2 - t and was simply and quickly formulated when we assumed that the power distribution across each surface was uniform. Our...power per unit area leaving A,, its radiosity B,, consists of two components. The direct emission is kIwT1 4 . The diffusely t reflected portion of the...leaving Am, the radiosity Ba, is the radiation power arriving at the aperture from the concentrator. It is given by B2 = P/A 2 = IAA4-/A 2 , (5) where

Implementation and Performance Evaluation of a Regenerative Braking System Coupled to Ultracapacitors for a Brushless DC Hub Motor Driven Electric Tricycle

OpenAIRE

Kuruppu, Sandun

2010-01-01

Research related to electrical vehicles is gaining importance due to the, energy crisis. An electric vehicle itself is far ahead of an internal combustion, engine based vehicle due to its efficiency. Using regenerative braking when, braking, improves the efficiency of an electric vehicle as it recovers energy that, could go to waste if mechanical brakes were used. A novel regenerative braking, system for neighborhood electric vehicles was designed, prototyped and tested., The proposed system ...

Canadians' support for radical life extension resulting from advances in regenerative medicine.

Science.gov (United States)

Dragojlovic, Nick

2013-04-01

This paper explores Canadian public perceptions of a hypothetical scenario in which a radical increase in life expectancy results from advances in regenerative medicine. A national sample of 1231 adults completed an online questionnaire on stem cell research and regenerative medicine, including three items relating to the possibility of Canadians' average life expectancy increasing to 120 years by 2050. Overall, Canadians are strongly supportive of the prospect of extended lifespans, with 59% of the sample indicating a desire to live to 120 if scientific advances made it possible, and 47% of respondents agreeing that such increases in life expectancy are possible by 2050. The strongest predictors of support for radical life extension are individuals' general orientation towards science and technology and their evaluation of its plausibility. These results contrast with previous research, which has suggested public ambivalence for biomedical life extension, and point to the need for more research in this area. They suggest, moreover, that efforts to increase public awareness about anti-aging research are likely to increase support for the life-extending consequences of that research program. Copyright © 2013 Elsevier Inc. All rights reserved.

Induced pluripotent stem cells reprogramming: Epigenetics and applications in the regenerative medicine

Directory of Open Access Journals (Sweden)

Kátia Maria Sampaio Gomes

Full Text Available Summary Induced pluripotent stem cells (iPSCs are somatic cells reprogrammed into an embryonic-like pluripotent state by the expression of specific transcription factors. iPSC technology is expected to revolutionize regenerative medicine in the near future. Despite the fact that these cells have the capacity to self-renew, they present low efficiency of reprogramming. Recent studies have demonstrated that the previous somatic epigenetic signature is a limiting factor in iPSC performance. Indeed, the process of effective reprogramming involves a complete remodeling of the existing somatic epigenetic memory, followed by the establishment of a "new epigenetic signature" that complies with the new type of cell to be differentiated. Therefore, further investigations of epigenetic modifications associated with iPSC reprogramming are required in an attempt to improve their self-renew capacity and potency, as well as their application in regenerative medicine, with a new strategy to reduce the damage in degenerative diseases. Our review aimed to summarize the most recent findings on epigenetics and iPSC, focusing on DNA methylation, histone modifications and microRNAs, highlighting their potential in translating cell therapy into clinics.

Advances in the design and higher-order assembly of collagen mimetic peptides for regenerative medicine.

Science.gov (United States)

Strauss, Kevin; Chmielewski, Jean

2017-08-01

Regenerative medicine makes use of cell-supporting biomaterials to replace lost or damaged tissue. Collagen holds great potential in this regard caused by its biocompatibility and structural versatility. While natural collagen has shown promise for regenerative medicine, collagen mimetic peptides (CMPs) have emerged that allow far higher degrees of customization and ease of preparation. A wide range of two and three-dimensional assemblies have been generated from CMPs, many of which accommodate cellular adhesion and encapsulation, through careful sequence design and the exploitation of electrostatic and hydrophobic forces. But the methodology that has generated the greatest plethora of viable biomaterials is metal-promoted assembly of CMP triple helices-a rapid process that occurs under physiological conditions. Architectures generated in this manner promote cell growth, enable directed attachment of bioactive cargo, and produce living tissue. Copyright © 2017 Elsevier Ltd. All rights reserved.

Injection seeded, diode pumped regenerative ring Nd:YAG amplifier for spaceborne laser ranging technology development

Science.gov (United States)

Coyle, D. Barry; Kay, Richard B.; Degnan, John J.; Krebs, Danny J.; Seery, Bernard D.

1992-01-01

A small, all solid state, regenerative ring amplifier designed as a prototype for space application is discussed. Novel features include dual side pumping of the Nd:YAG crystal and a triangular ring cavity design which minimizes the number of optical components and losses. The amplifier is relatively small (3 ns round trip time) even though standard optical elements are employed. The ring regeneratively amplifies a 100 ps single pulse by approximately 10(exp 5) at a repetition rate of 10 to 100 Hz. The amplifier is designed to be injection seeded with a pulsed, 100 ps laser diode at 1.06 microns, but another Nd:YAG laser system supplying higher pulse energies was employed for laboratory experiment. This system is a prototype laser oscillator for the Geoscience Laser Ranging System (GLRS) platform. Results on measurements of beam quality, astigmatism, and gain are given.

Osteopontin ablation ameliorates muscular dystrophy by shifting macrophages to a pro-regenerative phenotype

Science.gov (United States)

Capote, Joana; Martinez, Leonel; Vetrone, Sylvia; Barton, Elisabeth R.; Sweeney, H. Lee; Miceli, M. Carrie

2016-01-01

In the degenerative disease Duchenne muscular dystrophy, inflammatory cells enter muscles in response to repetitive muscle damage. Immune factors are required for muscle regeneration, but chronic inflammation creates a profibrotic milieu that exacerbates disease progression. Osteopontin (OPN) is an immunomodulator highly expressed in dystrophic muscles. Ablation of OPN correlates with reduced fibrosis and improved muscle strength as well as reduced natural killer T (NKT) cell counts. Here, we demonstrate that the improved dystrophic phenotype observed with OPN ablation does not result from reductions in NKT cells. OPN ablation skews macrophage polarization toward a pro-regenerative phenotype by reducing M1 and M2a and increasing M2c subsets. These changes are associated with increased expression of pro-regenerative factors insulin-like growth factor 1, leukemia inhibitory factor, and urokinase-type plasminogen activator. Furthermore, altered macrophage polarization correlated with increases in muscle weight and muscle fiber diameter, resulting in long-term improvements in muscle strength and function in mdx mice. These findings suggest that OPN ablation promotes muscle repair via macrophage secretion of pro-myogenic growth factors. PMID:27091452

Regenerative Braking Compensatory Control Strategy Considering CVT Power Loss for Hybrid Electric Vehicles

Directory of Open Access Journals (Sweden)

Yang Yang

2018-02-01

Full Text Available Hybrid electric vehicles (HEV equipped with continuously variable transmission (CVT adjust the motor operating point continuously to achieve the optimal motor operating efficiency during regenerative braking. Traditional control strategies consider the CVT efficiency as constant, while the CVT efficiency varies in different operating conditions. In order to reflect the transmission efficiency more accurately during regenerative braking, the CVT theoretical torque loss model is firstly established which then leads to the battery–front motor–CVT joint operating efficiency model. The joint operating efficiency model indicates that the system efficiency is influenced by input speed, input torque, CVT speed ratio, and battery SOC (state of charge. The compensatory strategy for the front motor barking force is proposed to make full use of its braking power and the CVT speed ratio control strategy is modified to maintain the optimal operating efficiency of the system. The simulations are performed under three typical braking conditions and UDDS, NYCC, US06 respectively, the results show that the modified control strategy increases the front motor braking power and improves the system operating efficiency.

Energy Saving Performance Analysis of An Inverter-based Regenerative Power Re-utilization Device for Urban Rail Transit

Science.gov (United States)

Li, Jin; Qiu, Zhiling; Hu, Leilei

2018-04-01

The inverter-based regenerative braking power utilization devices can re-utilize the regenerative energy, thus reduce the energy consumption of urban rail transit. In this paper the power absorption principle of the inverter-based device is introduced, then the key influencing factors of energy saving performance are analyzed based on the absorption model. The field operation data verified that the control DC voltage plays an important role and lower control DC voltage yields more energy saving. Also, the one year energy saving performance data of an inverter-based re-utilization device located in NanJing S8 line is provided, and more than 1.2 million kWh energy is recovered in the one year operation.

ECM and ECM-like materials - Biomaterials for applications in regenerative medicine and cancer therapy.

Science.gov (United States)

Hinderer, Svenja; Layland, Shannon Lee; Schenke-Layland, Katja

2016-02-01

Regenerative strategies such as stem cell-based therapies and tissue engineering applications are being developed with the aim to replace, remodel, regenerate or support damaged tissues and organs. In addition to careful cell type selection, the design of appropriate three-dimensional (3D) scaffolds is essential for the generation of bio-inspired replacement tissues. Such scaffolds are usually made of degradable or non-degradable biomaterials and can serve as cell or drug carriers. The development of more effective and efficient drug carrier systems is also highly relevant for novel cancer treatment strategies. In this review, we provide a summary of current approaches that employ ECM and ECM-like materials, or ECM-synthetic polymer hybrids, as biomaterials in the field of regenerative medicine. We further discuss the utilization of such materials for cell and drug delivery, and highlight strategies for their use as vehicles for cancer therapy. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

Fibrin glue as the cell-delivery vehicle for mesenchymal stromal cells in regenerative medicine.

Science.gov (United States)

Wu, Xiuwen; Ren, Jianan; Li, Jieshou

2012-05-01

The use of tissue-engineering techniques such as stem-cell therapy to renew injured tissues is a promising strategy in regenerative medicine. As a cell-delivery vehicle, fibrin glues (FG) facilitate cell attachment, growth and differentiation and, ultimately, tissue formation and organization by its three-dimensional structure. Numerous studies have provided evidence that stromal cells derived from bone marrow (bone marrow stromal cells; BMSC) and adipose tissue (adipose-derived stromal cells; ADSC) contain a population of adult multipotent mesenchymal stromal cells (MSC) and endothelial progenitor cells that can differentiate into several lineages. By combining MSC with FG, the implantation could take advantage of the mutual benefits. Researchers and physicians have pinned their hopes on stem cells for developing novel approaches in regenerative medicine. This review focuses on the therapeutic potential of MSC with FG in bone defect reconstruction, cartilage and tendon injury repair, ligament, heart and nerve regeneration, and, furthermore, wound healing.

Tracking the engraftment and regenerative capabilities of transplanted lung stem cells using fluorescent nanodiamonds.

Science.gov (United States)

Wu, Tsai-Jung; Tzeng, Yan-Kai; Chang, Wei-Wei; Cheng, Chi-An; Kuo, Yung; Chien, Chin-Hsiang; Chang, Huan-Cheng; Yu, John

2013-09-01

Lung stem/progenitor cells are potentially useful for regenerative therapy, for example in repairing damaged or lost lung tissue in patients. Several optical imaging methods and probes have been used to track how stem cells incorporate and regenerate themselves in vivo over time. However, these approaches are limited by photobleaching, toxicity and interference from background tissue autofluorescence. Here we show that fluorescent nanodiamonds, in combination with fluorescence-activated cell sorting, fluorescence lifetime imaging microscopy and immunostaining, can identify transplanted CD45(-)CD54(+)CD157(+) lung stem/progenitor cells in vivo, and track their engraftment and regenerative capabilities with single-cell resolution. Fluorescent nanodiamond labelling did not eliminate the cells' properties of self-renewal and differentiation into type I and type II pneumocytes. Time-gated fluorescence imaging of tissue sections of naphthalene-injured mice indicates that the fluorescent nanodiamond-labelled lung stem/progenitor cells preferentially reside at terminal bronchioles of the lungs for 7 days after intravenous transplantation.

Attenuated Innate Immunity in Embryonic Stem Cells and Its Implications in Developmental Biology and Regenerative Medicine.

Science.gov (United States)

Guo, Yan-Lin; Carmichael, Gordon G; Wang, Ruoxing; Hong, Xiaoxiao; Acharya, Dhiraj; Huang, Faqing; Bai, Fengwei

2015-11-01

Embryonic stem cells (ESCs) represent a promising cell source for regenerative medicine. Intensive research over the past 2 decades has led to the feasibility of using ESC-differentiated cells (ESC-DCs) in regenerative medicine. However, increasing evidence indicates that ESC-DCs generated by current differentiation methods may not have equivalent cellular functions to their in vivo counterparts. Recent studies have revealed that both human and mouse ESCs as well as some types of ESC-DCs lack or have attenuated innate immune responses to a wide range of infectious agents. These findings raise important concerns for their therapeutic applications since ESC-DCs, when implanted to a wound site of a patient, where they would likely be exposed to pathogens and inflammatory cytokines. Understanding whether an attenuated immune response is beneficial or harmful to the interaction between host and grafted cells becomes an important issue for ESC-based therapy. A substantial amount of recent evidence has demonstrated that the lack of innate antiviral responses is a common feature to ESCs and other types of pluripotent cells. This has led to the hypothesis that mammals may have adapted different antiviral mechanisms at different stages of organismal development. The underdeveloped innate immunity represents a unique and uncharacterized property of ESCs that may have important implications in developmental biology, immunology, and in regenerative medicine. © 2015 AlphaMed Press.

Disease-in-a-dish: the contribution of patient-specific induced pluripotent stem cell technology to regenerative rehabilitation.

Science.gov (United States)

Mack, David L; Guan, Xuan; Wagoner, Ashley; Walker, Stephen J; Childers, Martin K

2014-11-01

Advances in regenerative medicine technologies will lead to dramatic changes in how patients in rehabilitation medicine clinics are treated in the upcoming decades. The multidisciplinary field of regenerative medicine is developing new tools for disease modeling and drug discovery based on induced pluripotent stem cells. This approach capitalizes on the idea of personalized medicine by using the patient's own cells to discover new drugs, increasing the likelihood of a favorable outcome. The search for compounds that can correct disease defects in the culture dish is a conceptual departure from how drug screens were done in the past. This system proposes a closed loop from sample collection from the diseased patient, to in vitro disease model, to drug discovery and Food and Drug Administration approval, to delivering that drug back to the same patient. Here, recent progress in patient-specific induced pluripotent stem cell derivation, directed differentiation toward diseased cell types, and how those cells can be used for high-throughput drug screens are reviewed. Given that restoration of normal function is a driving force in rehabilitation medicine, the authors believe that this drug discovery platform focusing on phenotypic rescue will become a key contributor to therapeutic compounds in regenerative rehabilitation.

New tools in regenerative medicine: gene therapy.

Science.gov (United States)

Muñoz Ruiz, Miguel; Regueiro, José R

2012-01-01

Gene therapy aims to transfer genetic material into cells to provide them with new functions. A gene transfer agent has to be safe, capable of expressing the desired gene for a sustained period of time in a sufficiently large population of cells to produce a biological effect. Identifying a gene transfer tool that meets all of these criteria has proven to be a difficult objective. Viral and nonviral vectors, in vivo, ex vivo and in situ strategies co-exist at present, although ex vivo lenti-or retroviral vectors are presently the most popular.Natural stem cells (from embryonic, hematopoietic, mesenchymal, or adult tissues) or induced progenitor stem (iPS) cells can be modified by gene therapy for use in regenerative medicine. Among them, hematopoietic stem cells have shown clear clinical benefit, but iPS cells hold humongous potential with no ethical concerns.

Investigation of the feasibility of the solar-/geothermally-assisted heat supply system Gesotherm S; Untersuchung der Durchfuehrbarkeit des solar-/ geothermisch gestuetzten Waermeversorgungssystems Gesotherm S

Energy Technology Data Exchange (ETDEWEB)

Liebisch, H. [EKT Energie und Kommunal-Technologie GmbH, Berlin (Germany)

1998-12-31

The project has been running since 1st March 1998 and is supposed to investigate the technical feasibility and economic efficiency of the Gesotherm S heat supply system in the residential area Berlin-Biesdorf/Habichtshorst (1,000 flats). Main points of investigation are: proof of feasibility and geothermal analysis of the deep pit; analysis of storage possibilities and technical synergies of combined solar-geothermal operation; determination of the regenerative supply ratio; calculation of economic efficiency; estimation of cost-saving potentials. The whole system is simulated for these studies. A new simulation model was developed for the pit. Simulations are based on the SMILE-simulation environment developed by the Technical University of Berlin. First estimates indicate costs of DM 200 per MWh without subsidies. (orig.) [Deutsch] Mit dem seit 1. Maerz 1998 laufenden Vorhaben soll die technische Realisierbarkeit und wirtschaftliche Attraktivitaet des Waermeversorgungssystems Gesotherm S am Beispiel der Nahwaermeversorgung eines Wohngebietes (ca. 1.000 WE) in Berlin-Biesdorf/Habichtshorst umfassend untersucht werden. Schwerpunkte der Untersuchung: - Machbarkeitsnachweis und geothermische Analyse der Tiefensonde - Analyse der Speichermoeglichkeiten und der technischen Synergieeffekte des solar-/geothermischen Kombinationsbetriebes - Ermittlung der regenerativen Deckungsrate - Berechnung der Wirtschaftlichkeit - Abschaetzung der Kostensenkungspotentiale. Fuer die Untersuchung wird das Gesamtsystem simuliert. Speziell fuer die Tiefensonde wird ein neues Simulationsmodell entwickelt. Basis ist die, an der TU-Berlin entwickelte, Simulationsumgebung SMILE. Erste Abschaetzungen ergaben Waermekosten ohne Subventionen von unter 200 DM/MWh. (orig.)

Retreatment of failed regenerative endodontic of orthodontically treated immature permanent maxillary central incisor: a case report

Directory of Open Access Journals (Sweden)

Musaed Fahad Al-Tammami

2017-02-01

Full Text Available A revascularization procedure was shown to be the best alternative therapy for immature teeth with necrotic pulp and apical infection. A 12 year old female with a history of trauma to her upper central incisor and a sinus tract was referred for endodontic treatment. She was an active orthodontic patient and had undergone regenerative endodontic treatment for the past 2 years. Clinical examination revealed no response to sensibility, percussion, and palpation tests. The preoperative radiograph showed an open apex and apical rarefaction. The case was diagnosed as previously treated tooth with asymptomatic apical periodontitis. Regenerative endodontic retreatment was performed, and the case was followed for 3 years. Clinical, radiographic, and cone-beam computed tomography follow-up examination revealed an asymptomatic tooth, with evidence of periapical healing and root maturation.

Development of a Microwave Regenerative Sorbent-Based Hydrogen Purifier

Science.gov (United States)

Wheeler, Richard R., Jr.; Dewberry, Ross H.; McCurry, Bryan D.; Abney, Morgan B.; Greenwood, Zachary W.

2016-01-01

This paper describes the design and fabrication of a Microwave Regenerative Sorbent-based Hydrogen Purifier (MRSHP). This unique microwave powered technology was developed for the purification of a hydrogen stream produced by the Plasma Pyrolysis Assembly (PPA). The PPA is a hydrogen recovery (from methane) post processor for NASA's Sabatier-based carbon dioxide reduction process. Embodied in the Carbon dioxide Reduction Assembly (CRA), currently aboard the International Space Station (ISS), the Sabatier reaction employs hydrogen to catalytically recover oxygen, in the form of water, from respiratory carbon dioxide produced by the crew. This same approach is base-lined for future service in the Air Revitalization system on extended missions into deep space where resupply is not practical. Accordingly, manned exploration to Mars may only become feasible with further closure of the air loop as afforded by the greater hydrogen recovery permitted by the PPA with subsequent hydrogen purification. By utilizing the well-known high sorbate loading capacity of molecular sieve 13x, coupled with microwave dielectric heating phenomenon, MRSHP technology is employed as a regenerative filter for a contaminated hydrogen gas stream. By design, freshly regenerated molecular sieve 13x contained in the MRSHP will remove contaminants from the effluent of a 1-CM scale PPA for several hours prior to breakthrough. By reversing flow and pulling a relative vacuum the MRSHP prototype then uses 2.45 GHz microwave power, applied through a novel coaxial antenna array, to rapidly heat the sorbent bed and drive off the contaminants in a short duration vacuum/thermal contaminant desorption step. Finally, following rapid cooling via room temperature cold plates, the MRSHP is again ready to serve as a hydrogen filter.

Quantitative evaluation of RASSF1A methylation in the non-lesional, regenerative and neoplastic liver

Science.gov (United States)

Di Gioia, Sonia; Bianchi, Paolo; Destro, Annarita; Grizzi, Fabio; Malesci, Alberto; Laghi, Luigi; Levrero, Massimo; Morabito, Alberto; Roncalli, Massimo

2006-01-01

Background Epigenetic changes during ageing and their relationship with cancer are under the focus of intense research. RASSF1A and NORE1A are novel genes acting in concert in the proapoptotic pathway of the RAS signalling. While NORE1A has not been previously investigated in the human liver, recent reports have suggested that RASSF1A is frequently epigenetically methylated not only in HCC but also in the cirrhotic liver. Methods To address whether epigenetic changes take place in connection to age and/or to the underlying disease, we investigated RASSF1A and NORE1A gene promoter methylation by conventional methylation specific PCR and Real-Time MSP in a series of hepatitic and non-hepatitic livers harboring regenerative/hyperplastic (cirrhosis/focal nodular hyperplasia), dysplastic (large regenerative, low and high grade dysplastic nodules) and neoplastic (hepatocellular adenoma and carcinoma) growths. Results In the hepatitic liver (chronic hepatitic/cirrhosis, hepatocellular nodules and HCC) we found widespread RASSF1A gene promoter methylation with a methylation index that increased from regenerative conditions (cirrhosis) to hepatocellular nodules (p < 0.01) to HCC (p < 0.001). In the non-hepatitic liver a consistent pattern of gene methylation was also found in both lesional (focal nodular hyperplasia and hepatocellular adenoma) and non-lesional tissue. Specifically, hepatocellular adenomas (HA) showed a methylation index significantly higher than that detected in focal nodular hyperplasia (FNH) (p < 0.01) and in non-lesional tissue (p < 0.001). In non-lesional liver also the methylation index gradually increased by ageing (p = 0.002), suggesting a progressive spreading of methylated cells over time. As opposed to RASSF1A gene promoter methylation, NORE1A gene was never found epigenetically alterated in both hepatitic and non-hepatitic liver. Conclusion We have shown that in non-lesional, regenerative and neoplastic liver the RASSF1A gene is increasingly

The application of an enamel matrix protein derivative (Emdogain) in regenerative periodontal therapy: a review.

NARCIS (Netherlands)

Sculean, A.; Schwarz, F.; Becker, J.; Brecx, M.

2007-01-01

Regenerative periodontal therapy aims at reconstitution of the lost periodontal structures such as new formation of root cementum, periodontal ligament and alveolar bone. Findings from basic research indicate that enamel matrix protein derivative (EMD) has a key role in periodontal wound healing.

Thermodynamic study of a regenerative atmospheric water distiller

International Nuclear Information System (INIS)

Costa, Gustavo Koury

1998-06-01

The need of water for human consumption in our region where there is a great storage of non saline sources has motivated the study of new desalination technologies. The present work introduces a water distiller whose main characteristic, in relation to other units, is the high production allied to a good efficiency. This equipment that promotes the reuse of the water condensation heat is then called Regenerative Distiller. A theoretical study of the thermodynamic process involved is made, resulting in a numeric model for the project of new units accordingly to the required demands. The theoretical results are also compared with experimental data obtained through the testing of prototype, built and put into operation by the FAE/DEN group of the Federal University of Pernambuco. (author)

Passive force balancing of an active magnetic regenerative liquefier

Science.gov (United States)

Teyber, R.; Meinhardt, K.; Thomsen, E.; Polikarpov, E.; Cui, J.; Rowe, A.; Holladay, J.; Barclay, J.

2018-04-01

Active magnetic regenerators (AMR) have the potential for high efficiency cryogen liquefaction. One active magnetic regenerative liquefier (AMRL) configuration consists of dual magnetocaloric regenerators that reciprocate in a persistent-mode superconducting solenoid. Issues with this configuration are the spatial and temporal magnetization gradients that induce large magnetic forces and winding currents. To solve the coupled problem, we present a force minimization approach using passive magnetic material to balance a dual-regenerator AMR. A magnetostatic model is developed and simulated force waveforms are compared with experimental measurements. A genetic algorithm identifies force-minimizing passive structures with virtually ideal balancing characteristics. Implementation details are investigated which affirm the potential of the proposed methodology.

Concise Review: Amniotic Fluid Stem Cells: The Known, the Unknown, and Potential Regenerative Medicine Applications.

Science.gov (United States)

Loukogeorgakis, Stavros P; De Coppi, Paolo

2017-07-01

The amniotic fluid has been identified as an untapped source of cells with broad potential, which possess immunomodulatory properties and do not have the ethical and legal limitations of embryonic stem cells. CD117(c-Kit)+ cells selected from amniotic fluid have been shown to differentiate into cell lineages representing all three embryonic germ layers without generating tumors, making them ideal candidates for regenerative medicine applications. Moreover, their ability to engraft in injured organs and modulate immune and repair responses of host tissues, suggest that transplantation of such cells may be useful for the treatment of various degenerative and inflammatory diseases. Although significant questions remain regarding the origin, heterogeneous phenotype, and expansion potential of amniotic fluid stem cells, evidence to date supports their potential role as a valuable stem cell source for the field of regenerative medicine. Stem Cells 2017;35:1663-1673. © 2016 AlphaMed Press.

Regenerative Medicine: A Vehicle to Infuse Laboratory-Bench Modules into an Exercise Physiology Curriculum

Science.gov (United States)

Brown, Jason M.; Guy, Breonte S.; Henderson, Dawn X.; Ebert, C. Edward; Harp, Jill; Markert, Chad D.

2018-01-01

Regenerative medicine is a novel discipline that both excites undergraduates and may be used as a vehicle to expose students to scientific concepts and opportunities. The goal of this article is to describe the implementation of a National Science Foundation-funded Targeted Infusion Project in which underrepresented minority undergraduates are…

Optimization of solar-powered Stirling heat engine with finite-time thermodynamics

Energy Technology Data Exchange (ETDEWEB)

Yaqi, Li [School of Energy and Power Engineering, Xi' an Jiaotong University, Xi' an, Shaanxi 710049 (China); Xi' an Research Institute of Hi-Tech, Xi' an, Shaanxi 710025 (China); Yaling, He; Weiwei, Wang [School of Energy and Power Engineering, Xi' an Jiaotong University, Xi' an, Shaanxi 710049 (China)

2011-01-15

A mathematical model for the overall thermal efficiency of the solar-powered high temperature differential dish-Stirling engine with finite-rate heat transfer, regenerative heat losses, conductive thermal bridging losses and finite regeneration processes time is developed. The model takes into consideration the effect of the absorber temperature and the concentrating ratio on the thermal efficiency; radiation and convection heat transfer between the absorber and the working fluid as well as convection heat transfer between the heat sink and the working fluid. The results show that the optimized absorber temperature and concentrating ratio are at about 1100 K and 1300, respectively. The thermal efficiency at optimized condition is about 34%, which is not far away from the corresponding Carnot efficiency at about 50%. Hence, the present analysis provides a new theoretical guidance for designing dish collectors and operating the Stirling heat engine system. (author)

Seamless vascularized large-diameter tubular collagen scaffolds reinforced with polymer knittings for esophageal regenerative medicine

NARCIS (Netherlands)

Hoogenkamp, H.R.; Koens, M.J.W.; Geutjes, P.J.; Ainoedhofer, H.; Wanten, G.J.A.; Tiemessen, D.M.; Hilborn, J.; Gupta, B.; Feitz, W.F.J.; Daamen, W.F.; Saxena, A.K.; Oosterwijk, E.; Kuppevelt, T.H. van

2014-01-01

A clinical demand exists for alternatives to repair the esophagus in case of congenital defects, cancer, or trauma. A seamless biocompatible off-the-shelf large-diameter tubular scaffold, which is accessible for vascularization, could set the stage for regenerative medicine of the esophagus. The use

Ultra-stable, diode-pumped Nd-doped glass regenerative amplifier for the National Ignition Facility (NIF)

International Nuclear Information System (INIS)

Crane, J.K.; Martinez, M.; Beach, R.J.; Mitchell, S.; Pratt, G.; Christensen, J.J.

1995-12-01

We describe a diode laser-pumped Nd:glass regenerative amplifier that amplifies temporally shaped pulses with low distortion, high pulse-to- pulse stability, and high gain. This laser amplifier is a prototype subsystem for the National Ignition Facility (NIF) laser system. 2 refs., 1 fig

Investigation of Bio-Regenerative Life Support and Trash-to-Gas Experiment on a 4-Month Mars Simulation Mission

Science.gov (United States)

Caraccio, Anne; Poulet, Lucie; Hintze, Paul E.; Miles, John D.

2014-01-01

Future crewed missions to other planets or deep space locations will require regenerative Life Support Systems (LSS) as well as recycling processes for mission waste. Constant resupply of many commodity materials will not be a sustainable option for deep space missions, nor will stowing trash on board a vehicle or at a lunar or Martian outpost. The habitable volume will decline as the volume of waste increases. A complete regenerative environmentally controlled life support system (ECLSS) on an extra-terrestrial outpost will likely include physico-chemical and biological technologies, such as bioreactors and greenhouse modules. Physico-chemical LSS do not enable food production and bio-regenerative LSS are not stable enough to be used alone in space. Mission waste that cannot be recycled into the bio-regenerative ECLSS can include excess food, food packaging, clothing, tape, urine and fecal waste. This waste will be sent to a system for converting the trash into high value products. Two crew members on a 120 day Mars analog simulation, in collaboration with Kennedy Space Centers (KSC) Trash to Gas (TtG) project investigated a semi-closed loop system that treated non-edible biomass and other logistical waste for volume reduction and conversion into useful commodities. The purpose of this study is to show how plant growth affects the amount of resources required by the habitat and how spent plant material can be recycled. Real-time data was sent to the reactor at KSC in Florida for replicating the analog mission waste for laboratory operation. This paper discusses the 120 day mission plant growth activity, logistical and plant waste management, power and water consumption effects of the plant and logistical waste, and potential energy conversion techniques using KSCs TtG technology.

Investigation of Bio-Regenerative Life Support and Trash-To-Gas Experiment on a 4 Month Mars Simulation Mission

Science.gov (United States)

Caraccio, Anne; Poulet, Lucie; Hintze, Paul E.; Miles, John D.

2014-01-01

Future crewed missions to other planets or deep space locations will require regenerative Life Support Systems (LSS) as well as recycling processes for mission waste. Constant resupply of many commodity materials will not be a sustainable option for deep space missions, nor will storing trash on board a vehicle or at a lunar or Martian outpost. The habitable volume will decline as the volume of waste increases. A complete regenerative environmentally controlled life support system (ECLSS) on an extra-terrestrial outpost will likely include physico-chemical and biological technologies, such as bioreactors and greenhouse modules. Physico-chemical LSS do not enable food production and bio-regenerative LSS are not stable enough to be used alone in space. Mission waste that cannot be recycled into the bio-regenerative ECLSS can include excess food, food packaging, clothing, tape, urine and fecal waste. This waste will be sent to a system for converting the trash into the high value products. Two crew members on a 120 day Mars analog simulation, in collaboration with Kennedy Space Centers (KSC) Trash to Gas (TtG) project investigated a semi-closed loop system that treated non-edible biomass and other logistical waste for volume reduction and conversion into useful commodities. The purposes of this study are to show the how plant growth affects the amount of resources required by the habitat and how spent plant material can be recycled. Real-time data was sent to the reactor at KSC in Florida for replicating the analog mission waste for laboratory operation. This paper discusses the 120 day mission plant growth activity, logistical and plant waste management, power and water consumption effects of the plant and logistical waste, and potential energy conversion techniques using KSCs TtG reactor technology.

Regenerative medicine in kidney disease: where we stand and where to go.

Science.gov (United States)

Borges, Fernanda T; Schor, Nestor

2017-07-22

The kidney is a complex organ with more than 20 types of specialized cells that play an important role in maintaining the body's homeostasis. The epithelial tubular cell is formed during embryonic development and has little proliferative capacity under physiological conditions, but after acute injury the kidney does have regenerative capacity. However, after repetitive or severe lesions, it may undergo a maladaptation process that predisposes it to chronic kidney injury. Regenerative medicine includes various repair and regeneration techniques, and these have gained increasing attention in the scientific literature. In the future, not only will these techniques contribute to the repair and regeneration of the human kidney, but probably also to the construction of an entire organ. New mechanisms studied for kidney regeneration and repair include circulating stem cells as mesenchymal stromal/stem cells and their paracrine mechanisms of action; renal progenitor stem cells; the leading role of tubular epithelial cells in the tubular repair process; the study of zebrafish larvae to understand the process of nephron development, kidney scaffold and its repopulation; and, finally, the development of organoids. This review elucidates where we are in terms of current scientific knowledge regarding these mechanisms and the promises of future scientific perspectives.

A regenerative approach towards mucosal fenestration closure

Science.gov (United States)

Gandi, Padma; Anumala, Naveen; Reddy, Amarender; Viswa Chandra, Rampalli

2013-01-01

Mucosal fenestration is an opening or an interstice through the oral mucosa. A lesion which occurs with greater frequency than generally realised, its occurrence is attributed to a myriad of causes. Mucogingival procedures including connective tissue grafts, free gingival grafts and lateral pedicle grafts are generally considered to be the treatment of choice in the closure of a mucosal fenestration. More often, these procedures are performed in conjunction with other procedures such as periradicular surgery and with bone grafts. However, the concomitant use of gingival grafts and bone grafts in mucosal fenestrations secondary to infections in sites exhibiting severe bone loss is highly debatable. In this article, we report two cases of mucosal fenestrations secondary to trauma and their management by regenerative periodontal surgery with the placement of guided tissue regeneration membrane and bone graft. The final outcome was a complete closure of the fenestration in both the cases. PMID:23749826

Bi-Mix Antimicrobial Scaffolds for Regenerative Endodontics

Science.gov (United States)

Palasuk, Jadesada; Kamocki, Krzysztof; Hippenmeyer, Lauren; Platt, Jeffrey A.; Spolnik, Kenneth J.; Gregory, Richard L.; Bottino, Marco C.

2014-01-01

Introduction Eliminating and/or inhibiting bacterial growth within the root canal system have been shown to play a key role in the regenerative outcome. The aim of this study was to synthesize and determine in vitro both the antimicrobial effectiveness and cytocompatibility of bi-mix antibiotic-containing polydioxanone (PDS)-based polymer scaffolds. Methods Antibiotic-containing (metronidazole, MET and ciprofloxacin, CIP) polymer solutions (distinct antibiotic weight ratios) were spun into fibers as a potential mimic to the double antibiotic paste (DAP, a MET/CIP mixture). Fiber morphology, chemical characteristics, and tensile strength were evaluated by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and tensile testing, respectively. Antimicrobial efficacy was tested over time (aliquot collection) against Enterococcus faecalis (Ef), Porphyromonas gingivalis (Pg), and Fusobacterium nucleatum (Fn). Similarly, cytotoxicity was evaluated in human dental pulp stem cells (hDPSCs). Data were statistically analyzed (pendodontics. PMID:25201643

Efficacy and safety of regenerative cell therapy for pulmonary arterial hypertension in animal models: a preclinical systematic review protocol.

Science.gov (United States)

Suen, Colin M; Zhai, Alex; Lalu, Manoj M; Welsh, Christopher; Levac, Brendan M; Fergusson, Dean; McIntyre, Lauralyn; Stewart, Duncan J

2016-05-25

Pulmonary arterial hypertension (PAH) is a rare disease (15 cases per million) that is characterized by widespread loss of the pulmonary microcirculation and elevated pulmonary vascular resistance leading to pathological right ventricular remodeling and ultimately right heart failure. Regenerative cell therapies (i.e., therapies involving cells with stem or progenitor-like properties) could potentially restore the effective lung microcirculation and provide a curative therapy for PAH. Preclinical evidence suggests that regenerative cell therapy using endothelial progenitor cells or mesenchymal stem cells may be beneficial in the treatment of PAH. These findings have led to the completion of a small number of human clinical trials, albeit with modest effect compared to animal studies. The objective of this systematic review is to compare the efficacy and safety of regenerative cell therapies in preclinical models of PAH as well as assess study quality to inform future clinical studies. We will include preclinical studies of PAH in which a regenerative cell type was administered and outcomes compared to a disease control. The primary outcome will be pulmonary hemodynamics as assessed by measurement of right ventricular systolic pressure and/or mean pulmonary arterial pressure. Secondary outcomes will include mortality, survival, right ventricular remodeling, pulmonary vascular resistance, cardiac output, cardiac index, pulmonary acceleration time, tricuspid annular systolic excursion, and right ventricular wall thickness. Electronic searches of MEDLINE and EMBASE databases will be constructed and reviewed by the Peer Review of Electronic Search Strategies (PRESS) process. Search results will be screened independently in duplicate. Data from eligible studies will be extracted, pooled, and analyzed using random effects models. Risk of bias will be assessed using the SYstematic Review Centre for Laboratory animal Experimentation (SYRCLE) risk of bias tool, and

Translating stem cell therapies: the role of companion animals in regenerative medicine

OpenAIRE

Volk, Susan W.; Theoret, Christine

2013-01-01

Veterinarians and veterinary medicine have been integral to the development of stem cell therapies. The contributions of large animal experimental models to the development and refinement of modern hematopoietic stem cell transplantation were noted nearly five decades ago. More recent advances in adult stem cell/regenerative cell therapies continue to expand knowledge of the basic biology and clinical applications of stem cells. A relatively liberal legal and ethical regulation of stem cell r...

Modeling hydraulic regenerative hybrid vehicles using AMESim and Matlab/Simulink

Science.gov (United States)

Lynn, Alfred; Smid, Edzko; Eshraghi, Moji; Caldwell, Niall; Woody, Dan

2005-05-01

This paper presents the overview of the simulation modeling of a hydraulic system with regenerative braking used to improve vehicle emissions and fuel economy. Two simulation software packages were used together to enhance the simulation capability for fuel economy results and development of vehicle and hybrid control strategy. AMESim, a hydraulic simulation software package modeled the complex hydraulic circuit and component hardware and was interlinked with a Matlab/Simulink model of the vehicle, engine and the control strategy required to operate the vehicle and the hydraulic hybrid system through various North American and European drive cycles.

Compact Water Vapor Exchanger for Regenerative Life Support Systems

Science.gov (United States)

Izenson, Michael G.; Chen, Weibo; Anderson, Molly; Hodgson, Edward

2012-01-01

Thermal and environmental control systems for future exploration spacecraft must meet challenging requirements for efficient operation and conservation of resources. Regenerative CO2 removal systems are attractive for these missions because they do not use consumable CO2 absorbers. However, these systems also absorb and vent water to space along with carbon dioxide. This paper describes an innovative device designed to minimize water lost from regenerative CO2 control systems. Design studies and proof-of-concept testing have shown the feasibility of a compact, efficient membrane water vapor exchanger (WVX) that will conserve water while meeting challenging requirements for operation on future spacecraft. Compared to conventional WVX designs, the innovative membrane WVX described here has the potential for high water recovery efficiency, compact size, and very low pressure losses. The key innovation is a method for maintaining highly uniform flow channels in a WVX core built from water-permeable membranes. The proof-of-concept WVX incorporates all the key design features of a prototypical unit, except that it is relatively small scale (1/23 relative to a unit sized for a crew of six) and some components were fabricated using non-prototypical methods. The proof-of-concept WVX achieved over 90% water recovery efficiency in a compact core in good agreement with analysis models. Furthermore the overall pressure drop is very small (less than 0.5 in. H2O, total for both flow streams) and meets requirements for service in environmental control and life support systems on future spacecraft. These results show that the WVX provides very uniform flow through flow channels for both the humid and dry streams. Measurements also show that CO2 diffusion through the water-permeable membranes will have negligible effect on the CO2 partial pressure in the spacecraft atmosphere.

Modality-Specific Axonal Regeneration: Towards selective regenerative neural interfaces

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Parisa eLotfi

2011-10-01

Full Text Available Regenerative peripheral nerve interfaces have been proposed as viable alternatives for the natural control of robotic prosthetic devices. However, sensory and motor axons at the neural interface are of mixed submodality types, which difficult the specific recording from motor axons and the eliciting of precise sensory modalities through selective stimulation. Here we evaluated the possibility of using type-specific neurotrophins to preferentially entice the regeneration of defined axonal populations from transected peripheral nerves into separate compartments. Segregation of mixed sensory fibers from dorsal root ganglion neurons was evaluated in vitro by compartmentalized diffusion delivery of nerve growth factor (NGF and neurotrophin-3 (NT-3, to preferentially entice the growth of TrkA+ nociceptive and TrkC+ proprioceptive subsets of sensory neurons, respectively. The average axon length in the NGF channel increased 2.5 fold compared to that in saline or NT-3, whereas the number of branches increased 3 fold in the NT-3 channels. These results were confirmed using a 3-D Y-shaped in vitro assay showing that the arm containing NGF was able to entice a 5-fold increase in axonal length of unbranched fibers. To address if such segregation can be enticed in vivo, a Y-shaped tubing was used to allow regeneration of the transected adult rat sciatic nerve into separate compartments filled with either NFG or NT-3. A significant increase in the number of CGRP+ pain fibers were attracted towards the sural nerve, while N-52+ large diameter axons were observed in the tibial and NT-3 compartments. This study demonstrates the guided enrichment of sensory axons in specific regenerative chambers, and supports the notion that neurotrophic factors can be used to segregate sensory and perhaps motor axons in separate peripheral interfaces.

Chitosan and Its Potential Use as a Scaffold for Tissue Engineering in Regenerative Medicine

Science.gov (United States)

Rodríguez-Vázquez, Martin; Vega-Ruiz, Brenda; Ramos-Zúñiga, Rodrigo; Saldaña-Koppel, Daniel Alexander; Quiñones-Olvera, Luis Fernando

2015-01-01

Tissue engineering is an important therapeutic strategy to be used in regenerative medicine in the present and in the future. Functional biomaterials research is focused on the development and improvement of scaffolding, which can be used to repair or regenerate an organ or tissue. Scaffolds are one of the crucial factors for tissue engineering. Scaffolds consisting of natural polymers have recently been developed more quickly and have gained more popularity. These include chitosan, a copolymer derived from the alkaline deacetylation of chitin. Expectations for use of these scaffolds are increasing as the knowledge regarding their chemical and biological properties expands, and new biomedical applications are investigated. Due to their different biological properties such as being biocompatible, biodegradable, and bioactive, they have given the pattern for use in tissue engineering for repair and/or regeneration of different tissues including skin, bone, cartilage, nerves, liver, and muscle. In this review, we focus on the intrinsic properties offered by chitosan and its use in tissue engineering, considering it as a promising alternative for regenerative medicine as a bioactive polymer. PMID:26504833

Concentrating Solar Power Projects - Planta Solar 20 | Concentrating Solar

Science.gov (United States)

Power | NREL 20 This page provides information on Planta Solar 20, a concentrating solar power Solar's Planta Solar 20 (PS20) is a 20-megawatt power tower plant being constructed next to the PS10 tower and increasing incident solar radiation capture will increase net electrical power output by 10

Model predictive control-based efficient energy recovery control strategy for regenerative braking system of hybrid electric bus

International Nuclear Information System (INIS)

Li, Liang; Zhang, Yuanbo; Yang, Chao; Yan, Bingjie; Marina Martinez, C.

2016-01-01

Highlights: • A 7-degree-of-freedom model of hybrid electric vehicle with regenerative braking system is built. • A modified nonlinear model predictive control strategy is developed. • The particle swarm optimization algorithm is employed to solve the optimization problem. • The proposed control strategy is verified by simulation and hardware-in-loop tests. • Test results verify the effectiveness of the proposed control strategy. - Abstract: As one of the main working modes, the energy recovered with regenerative braking system provides an effective approach so as to greatly improve fuel economy of hybrid electric bus. However, it is still a challenging issue to ensure braking stability while maximizing braking energy recovery. To solve this problem, an efficient energy recovery control strategy is proposed based on the modified nonlinear model predictive control method. Firstly, combined with the characteristics of the compound braking process of single-shaft parallel hybrid electric bus, a 7 degrees of freedom model of the vehicle longitudinal dynamics is built. Secondly, considering nonlinear characteristic of the vehicle model and the efficiency of regenerative braking system, the particle swarm optimization algorithm within the modified nonlinear model predictive control is adopted to optimize the torque distribution between regenerative braking system and pneumatic braking system at the wheels. So as to reduce the computational time of modified nonlinear model predictive control, a nearest point method is employed during the braking process. Finally, the simulation and hardware-in-loop test are carried out on road conditions with different tire–road adhesion coefficients, and the proposed control strategy is verified by comparing it with the conventional control method employed in the baseline vehicle controller. The simulation and hardware-in-loop test results show that the proposed strategy can ensure vehicle safety during emergency braking

An Overview of a Regenerative Fuel Cell Concept for a Mars Surface Mobile Element (Mars Rover)

Science.gov (United States)

Andersson, T.

2018-04-01

This paper outlines an overview of a regenerative fuel cell concept for a Mars rover. The objectives of the system are to provide electrical and thermal power during the Mars night and to provide electrical power for the operational cycles.

Regenerative Medicine for Neurological Disorders

Directory of Open Access Journals (Sweden)

Dong-Hyuk Park

2010-01-01

Full Text Available The annual meeting of the American Society for Neural Therapy and Repair (ASNTR has always introduced us to top-notch and up-to-date approaches for regenerative medicine related to neuroscience, ranging from stem cell–based therapy to novel drugs. The 16th ASNTR meeting focused on a variety of different topics, including the unknown pathogenesis or mechanisms of specific neurodegenerative diseases, stem cell biology, and development of novel alternative medicines or devices. Newly developed stem cells, such as amniotic epithelial stem cells and induced pluripotent stem cells, as well as well-known traditional stem cells, such as neural, embryonic, bone marrow mesenchymal, and human umbilical cord blood–derived stem cells, were reported. A number of commercialized stem cells were also covered at this meeting. Fetal neural tissues, such as ventral mesencephalon, striatum, and Schwann cells, were investigated for neurodegenerative diseases or spinal cord injury. A number of studies focused on novel methods for drug monitoring or graft tracking, and combination therapy with stem cells and medicine, such as cytokines or trophic factors. Finally, the National Institutes of Health guidelines for human stem cell research, clinical trials of commercialized stem cells without larger animal testing, and prohibition of medical tourism were big controversial issues that led to heated discussion.

Impact of the operation of non-displaced feedwater heaters on the performance of Solar Aided Power Generation plants

International Nuclear Information System (INIS)

Qin, Jiyun; Hu, Eric; Nathan, Graham J.

2017-01-01

Highlights: • Impact of non-displaced feedwater heater on plant’s performance has been evaluated. • Two operation strategies for non-displaced feedwater heater has been proposed. • Constant temperature strategy is generally better. • Constant mass flow rate strategy is suit for rich solar thermal input. - Abstract: Solar Aided Power Generation is a technology in which low grade solar thermal energy is used to displace the high grade heat of the extraction steam in a regenerative Rankine cycle power plant for feedwater preheating purpose. The displaced extraction steam can then expand further in the steam turbine to generate power. In such a power plant, using the (concentrated) solar thermal energy to displace the extraction steam to high pressure/temperature feedwater heaters (i.e. displaced feedwater heaters) is the most popular arrangement. Namely the extraction steam to low pressure/temperature feedwater heaters (i.e. non-displaced feedwater heaters) is not displaced by the solar thermal energy. In a Solar Aided Power Generation plants, when solar radiation/input changes, the extraction steam to the displaced feedwater heaters requires to be adjusted according to the solar radiation. However, for the extraction steams to the non-displaced feedwater heaters, it can be either adjusted accordingly following so-called constant temperature strategy or unadjusted i.e. following so-called constant mass flow rate strategy, when solar radiation/input changes. The previous studies overlooked the operation of non-displaced feedwater heaters, which has also impact on the whole plant’s performance. This paper aims to understand/reveal the impact of the two different operation strategies for non-displaced feedwater heaters on the plant’s performance. In this paper, a 300 MW Rankine cycle power plant, in which the extraction steam to high pressure/temperature feedwater heaters is displaced by the solar thermal energy, is used as study case for this purpose. It

Orthodontic-periodontal interactions: Orthodontic extrusion in interdisciplinary regenerative treatments.

Science.gov (United States)

Paolone, Maria Giacinta; Kaitsas, Roberto

2018-06-01

Orthodontics is a periodontal treatment. "Guided orthodontic regeneration" (GOR) procedures use orthodontic movements in perio-restorative patients. The GOR technique includes a guided orthodontic "soft tissue" regeneration (GOTR) and a guided orthodontic "bone" regeneration (GOBR) with a plastic soft tissue approach and a regenerating reality. The increased amount of soft tissue gained with orthodontic movement can be used for subsequent periodontal regenerative techniques. The increased amount of bone can as well improve primary implant stability and, eventually, simplify a GTR technique to regenerate soft tissues, to restore tooth with external resorption in aesthetic zone or to extract a tooth to create new hard-soft tissue for adjacent teeth. Copyright © 2018. Published by Elsevier Masson SAS.

Regenerative Carbonate-Based Thermochemical Energy Storage System for Concentrating Solar Power

Energy Technology Data Exchange (ETDEWEB)

Gangwal, Santosh [Southern Research Inst., Durham, NC (United States); Muto, Andrew [Southern Research Inst., Durham, NC (United States)

2017-08-30

Southern Research has developed a thermochemical energy storage (TCES) technology that utilizes the endothermic-exothermic reversible carbonation of calcium oxide (lime) to store thermal energy at high-temperatures, such as those achieved by next generation concentrating solar power (CSP) facilities. The major challenges addressed in the development of this system include refining a high capacity, yet durable sorbent material and designing a low thermal resistance low-cost heat exchanger reactor system to move heat between the sorbent and a heat transfer fluid under conditions relevant for CSP operation (e.g., energy density, reaction kinetics, heat flow). The proprietary stabilized sorbent was developed by Precision Combustion, Inc. (PCI). A factorial matrix of sorbent compositions covering the design space was tested using accelerated high throughput screening in a thermo-gravimetric analyzer. Several promising formulations were selected for more thorough evaluation and one formulation with high capacity (0.38 g CO₂/g sorbent) and durability (>99.7% capacity retention over 100 cycles) was chosen as a basis for further development of the energy storage reactor system. In parallel with this effort, a full range of currently available commercial and developmental heat exchange reactor systems and sorbent loading methods were examined through literature research and contacts with commercial vendors. Process models were developed to examine if a heat exchange reactor system and balance of plant can meet required TCES performance and cost targets, optimizing tradeoffs between thermal performance, exergetic efficiency, and cost. Reactor types evaluated included many forms, from microchannel reactor, to diffusion bonded heat exchanger, to shell and tube heat exchangers. The most viable design for application to a supercritical CO₂ power cycle operating at 200-300 bar pressure and >700°C was determined to be a combination of a diffusion bonded heat

Diffuse Muscular Pain, Skin Tightening, and Nodular Regenerative Hyperplasia Revealing Paraneoplastic Amyopathic Dermatomyositis due to Testicular Cancer

Directory of Open Access Journals (Sweden)

Sarah Norrenberg

2012-01-01

Full Text Available Paraneoplastic dermatomyositis (DM associated with testicular cancer is extremely rare. We report the case of a patient with skin tightening, polymyalgia, hypereosinophilia, and nodular regenerative hyperplasia revealing seminoma and associated paraneoplastic DM.

Genetic Dissection of Maize Embryonic Callus Regenerative Capacity Using Multi-Locus Genome-Wide Association Studies

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Langlang Ma

2018-04-01

Full Text Available The regenerative capacity of the embryonic callus, a complex quantitative trait, is one of the main limiting factors for maize transformation. This trait was decomposed into five traits, namely, green callus rate (GCR, callus differentiating rate (CDR, callus plantlet number (CPN, callus rooting rate (CRR, and callus browning rate (CBR. To dissect the genetic foundation of maize transformation, in this study multi-locus genome-wide association studies (GWAS for the five traits were performed in a population of 144 inbred lines genotyped with 43,427 SNPs. Using the phenotypic values in three environments and best linear unbiased prediction (BLUP values, as a result, a total of 127, 56, 160, and 130 significant quantitative trait nucleotides (QTNs were identified by mrMLM, FASTmrEMMA, ISIS EM-BLASSO, and pLARmEB, respectively. Of these QTNs, 63 QTNs were commonly detected, including 15 across multiple environments and 58 across multiple methods. Allele distribution analysis showed that the proportion of superior alleles for 36 QTNs was <50% in 31 elite inbred lines. Meanwhile, these superior alleles had obviously additive effect on the regenerative capacity. This indicates that the regenerative capacity-related traits can be improved by proper integration of the superior alleles using marker-assisted selection. Moreover, a total of 40 candidate genes were found based on these common QTNs. Some annotated genes were previously reported to relate with auxin transport, cell fate, seed germination, or embryo development, especially, GRMZM2G108933 (WOX2 was found to promote maize transgenic embryonic callus regeneration. These identified candidate genes will contribute to a further understanding of the genetic foundation of maize embryonic callus regeneration.

Distributed Antenna Channels with Regenerative Relaying: Relay Selection and Asymptotic Capacity

Directory of Open Access Journals (Sweden)

Aitor del Coso

2007-11-01

Full Text Available Multiple-input-multiple-output (MIMO techniques have been widely proposed as a means to improve capacity and reliability of wireless channels, and have become the most promising technology for next generation networks. However, their practical deployment in current wireless devices is severely affected by antenna correlation, which reduces their impact on performance. One approach to solve this limitation is relaying diversity. In relay channels, a set of N wireless nodes aids a source-destination communication by relaying the source data, thus creating a distributed antenna array with uncorrelated path gains. In this paper, we study this multiple relay channel (MRC following a decode-and-forward (D&F strategy (i.e., regenerative forwarding, and derive its achievable rate under AWGN. A half-duplex constraint on relays is assumed, as well as distributed channel knowledge at both transmitter and receiver sides of the communication. For this channel, we obtain the optimum relay selection algorithm and the optimum power allocation within the network so that the transmission rate is maximized. Likewise, we bound the ergodic performance of the achievable rate and derive its asymptotic behavior in the number of relays. Results show that the achievable rate of regenerative MRC grows as the logarithm of the Lambert W function of the total number of relays, that is, 𝒞=log⁡2(W0(N. Therefore, D&F relaying, cannot achieve the capacity of actual MISO channels.

Past and future of stem cells: from Prometheus to regenerative medicine

Directory of Open Access Journals (Sweden)

Gavino Faa

2016-09-01

Full Text Available The salamander limb regenerates completely after amputation and the heart of the zebrafish returns to normal even after an extensive injury. What is it that makes all this possible? The answer is the presence of stem cells, which in these animals are quite efficient. We humans have lost this capacity, but researchers are working incessantly to control cell reprogramming and make regenerative medicine possible and close at hand. It is probable that the ancient Greeks knew about the regenerative properties of the liver. Suffice it to recall the story of Prometheus. Different organs are considered: brain, heart, lung, kidney, adrenal glands, liver, pancreas, gut. Last but not least, we consider the stem cells of mother's milk which, from the neonatal intestinal lumen, are transported to the several organs, among which the brain, in which they become neurons, oligodendrocytes and astrocytes. This is a discovery that changes many things with respect to our knowledge today. Many actors are present on the stage in the archipelago of complexity and the uninterrupted string of perinatal programming which, from fetus to adult, orients and governs our health, for better or for worse. Proceedings of the 2nd International Course on Perinatal Pathology (part of the 11th International Workshop on Neonatology · October 26th-31st, 2015 · Cagliari (Italy · October 31st, 2015 · Stem cells: present and future Guest Editors: Gavino Faa, Vassilios Fanos, Antonio Giordano