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Full-Text Articles in Physical Sciences and Mathematics

Enabling An Equitable Energy Transition Through Inclusive Research, Michael Ash, Erin Baker, Mark Tuominen, Dhandapani Venkataraman, Matthew Burke, S. Castellanos, M. Cha, Gabe Chan, D. Djokic, J.C. Ford, Anna P. Goldstein, David Hsu, Matt Lacker, C. Miller, D. Nock, A.P. Ravikumar, Allison Bates, Anna Stefanopoulou, E Grubert, D.M Kammen, M. Pastor, S.Z, Attari, S. Carley, D.L Clark, D. Dean-Ryan, U. Kosar, Kerry Bowie, Tina Johnson Jan 2023

Enabling An Equitable Energy Transition Through Inclusive Research, Michael Ash, Erin Baker, Mark Tuominen, Dhandapani Venkataraman, Matthew Burke, S. Castellanos, M. Cha, Gabe Chan, D. Djokic, J.C. Ford, Anna P. Goldstein, David Hsu, Matt Lacker, C. Miller, D. Nock, A.P. Ravikumar, Allison Bates, Anna Stefanopoulou, E Grubert, D.M Kammen, M. Pastor, S.Z, Attari, S. Carley, D.L Clark, D. Dean-Ryan, U. Kosar, Kerry Bowie, Tina Johnson

ETI Publications

Comprehensive and meaningful inclusion of marginalized communities within the research enterprise will be critical to ensuring an equitable, technology-informed, clean energy transition. We provide five key action items for government agencies and philanthropic institutions to operationalize the commitment to an equitable energy transition.


Evidence For The Role Of Cyp51a And Xenobiotic Detoxification In Differential Sensitivity To Azole Fungicides In Boxwood Blight Pathogens, Stefanos Stravoravdis, Robert E. Marra, Nicholas R. Leblanc, Joanne Crouch, Jonathan P. Hulvey Jan 2021

Evidence For The Role Of Cyp51a And Xenobiotic Detoxification In Differential Sensitivity To Azole Fungicides In Boxwood Blight Pathogens, Stefanos Stravoravdis, Robert E. Marra, Nicholas R. Leblanc, Joanne Crouch, Jonathan P. Hulvey

Microbiology Department Faculty Publication Series

Boxwood blight, a fungal disease of ornamental plants (Buxus spp.), is caused by two sister species, Calonectria pseudonaviculata (Cps) and C. henricotiae (Che). Compared to Cps, Che is documented to display reduced sensitivity to fungicides, including the azole class of antifungals, which block synthesis of a key fungal membrane component, ergosterol. A previous study reported an ergosterol biosynthesis gene in Cps, CYP51A, to be a pseudogene, and RNA-Seq data confirm that a functional CYP51A is expressed only in Che. The lack of additional ergosterol biosynthesis genes showing significant differential expression suggests that the functional CYP51A in Che could contribute to …


Raising Dielectric Permittivity Mitigates Dopant-Induced Disorder In Conjugated Polymers, Meenakshi Upadhyaya, Michael Lu-Díaz, Subhayan Samanta, Muhammad Abdullah, Keith Dusoe, Kevin R. Kittilstved, Dhandapani Venkataraman, Zlatan Akšamija Jan 2021

Raising Dielectric Permittivity Mitigates Dopant-Induced Disorder In Conjugated Polymers, Meenakshi Upadhyaya, Michael Lu-Díaz, Subhayan Samanta, Muhammad Abdullah, Keith Dusoe, Kevin R. Kittilstved, Dhandapani Venkataraman, Zlatan Akšamija

Electrical and Computer Engineering Faculty Publication Series

Conjugated polymers need to be doped to increase charge carrier density and reach the electrical conductivity necessary for electronic and energy applications. While doping increases carrier density, Coulomb interactions between the dopant molecules and the localized carriers are poorly screened, causing broadening and a heavy tail in the electronic density-of-states (DOS). The authors examine the effects of dopant-induced disorder on two complimentary charge transport properties of semiconducting polymers, the Seebeck coefficient and electrical conductivity, and demonstrate a way to mitigate them. Their simulations, based on a modified Gaussian disorder model with Miller-Abrahams hopping rates, show that dopant-induced broadening of the …


Effective And Selective Dna Modification On Bacterial Membranes, Qian Tian, Yousef Bagheri, Puspam Keshri, Rigumula Wu, Kewei Ren, Qikun Yu, Mingxu You Jan 2021

Effective And Selective Dna Modification On Bacterial Membranes, Qian Tian, Yousef Bagheri, Puspam Keshri, Rigumula Wu, Kewei Ren, Qikun Yu, Mingxu You

Chemistry Department Faculty Publication Series

With highly precise self-assembly and programmability, DNA has been widely used as a versatile material in nanotechnology and synthetic biology. Recently, DNA-based nanostructures and devices have been engineered onto eukaryotic cell membranes for various exciting applications in the detection and regulation of cell functions. While in contrast, the potential of applying DNA nanotechnology for bacterial membrane studies is still largely underexplored, which is mainly due to the lack of tools to modify DNA on bacterial membranes. Herein, using lipid-DNA conjugates, we have developed a simple, fast, and highly efficient system to engineer bacterial membranes with designer DNA molecules. We have …


Polymeric Nanoparticles Active Against Dual-Species Bacterial Biofilms, Jessa Marie V. Makabenta, Jungmi Park, Cheng-Hsuan Li, Aritra Nath Chattopadhyay, Ahmed Nabawy, Ryan F. Landis, Akash Gupta, Suzannah Schmidt-Malan, Robin Patel, Vincent M. Rotello Jan 2021

Polymeric Nanoparticles Active Against Dual-Species Bacterial Biofilms, Jessa Marie V. Makabenta, Jungmi Park, Cheng-Hsuan Li, Aritra Nath Chattopadhyay, Ahmed Nabawy, Ryan F. Landis, Akash Gupta, Suzannah Schmidt-Malan, Robin Patel, Vincent M. Rotello

Chemistry Department Faculty Publication Series

Biofilm infections are a global public health threat, necessitating new treatment strategies. Biofilm formation also contributes to the development and spread of multidrug-resistant (MDR) bacterial strains. Biofilm-associated chronic infections typically involve colonization by more than one bacterial species. The co-existence of multiple species of bacteria in biofilms exacerbates therapeutic challenges and can render traditional antibiotics ineffective. Polymeric nanoparticles offer alternative antimicrobial approaches to antibiotics, owing to their tunable physico-chemical properties. Here, we report the efficacy of poly(oxanorborneneimide) (PONI)-based antimicrobial polymeric nanoparticles (PNPs) against multi-species bacterial biofilms. PNPs showed good dual-species biofilm penetration profiles as confirmed by confocal laser scanning microscopy. …


Exogenous Introduction Of Initiator And Executioner Caspases Results In Different Apoptotic Outcomes, Francesca Anson, S Thayumanavan, Jeanne A. Hardy Jan 2021

Exogenous Introduction Of Initiator And Executioner Caspases Results In Different Apoptotic Outcomes, Francesca Anson, S Thayumanavan, Jeanne A. Hardy

Chemistry Department Faculty Publication Series

The balance of pro-apoptotic and pro-survival proteins defines a cell's fate. These processes are controlled through an interdependent and finely tuned protein network that enables survival or leads to apoptotic cell death. The caspase family of proteases is central to this apoptotic network, with initiator and executioner caspases, and their interaction partners, regulating and executing apoptosis. In this work, we interrogate and modulate this network by exogenously introducing specific initiator or executioner caspase proteins. Each caspase is exogenously introduced using redox-responsive polymeric nanogels. Although caspase-3 might be expected to be the most effective due to the centrality of its role …


A Synergistic Anti-Diabetic Effect By Ginsenosides Rb1 And Rg3 Through Adipogenic And Insulin Signaling Pathways In 3t3-L1 Cells, Hee-Do Hong, Sun-Il Choi, Ok-Hwan Lee, Young-Cheul Kim Jan 2021

A Synergistic Anti-Diabetic Effect By Ginsenosides Rb1 And Rg3 Through Adipogenic And Insulin Signaling Pathways In 3t3-L1 Cells, Hee-Do Hong, Sun-Il Choi, Ok-Hwan Lee, Young-Cheul Kim

Nutrition Department Faculty Publication Series

Although ginsenosides Rb1 and Rg3 have been identified as the significant ginsenosides found in red ginseng that confer anti-diabetic actions, it is unclear whether insulin-sensitizing effects are mediated by the individual compounds or by their combination. To determine the effect of ginsenosides Rb1 and Rg3 on adipocyte differentiation, 3T3-L1 preadipocytes were induced to differentiate the standard hormonal inducers in the absence or presence of ginsenosides Rb1 or Rg3. Additionally, we determined the effects of Rb1, Rg3, or their combination on the expression of genes related to adipocyte differentiation, adipogenic transcription factors, and the insulin signaling pathway in 3T3-L1 cells using …


Solar Cells, D. Venkataraman Jan 2019

Solar Cells, D. Venkataraman

Science and Engineering Saturday Seminars

Solar cells convert the sun's energy into electrical energy. In this workshop, I will discuss the processes involved in solar cell and various types of solar cells that are being developed as an alternative to silicon solar cells. I will also demonstrate how students can build a solar cell from readily available materials.


Concentration, Amount And Counting By Weighing, Julian Tyson Jan 2018

Concentration, Amount And Counting By Weighing, Julian Tyson

Science and Engineering Saturday Seminars

Concentration, Amount and Counting by Weighing

UMass Amherst STEM Ed Institute Saturday Workshop 2/3/2018

Julian Tyson, Professor Emeritus, Department of Chemistry. Tyson@chem.umass.edu

Session 1. Introductions.

Ice-breaker: The elementarity contest.

Setting the scene: “How much arsenic do we eat?” Why do we want to know? The Consumer Reports articles (Nov 2012 and Nov 2014)

Dealing with really big and really small numbers.

Session 2. Amount, concentration

Solids, liquids and gases. The “parts per” concept.

Session 3. Counting by weighing

The count equation. Rice grains (the bottle content problem), atoms and molecules.. Chemical formulas and balanced chemical expressions. The numbers in the …


Persistent Radical Anion Polymers Based On Naphthalenediimide And A Vinylene Spacer, Sashi Debnath, Connor J. Boyle, Dongming Zhou, Bryan M. Wong, Kevin R. Kittilstved, Dhandapani Venkataraman Jan 2018

Persistent Radical Anion Polymers Based On Naphthalenediimide And A Vinylene Spacer, Sashi Debnath, Connor J. Boyle, Dongming Zhou, Bryan M. Wong, Kevin R. Kittilstved, Dhandapani Venkataraman

Chemistry Department Faculty Publication Series

Persistent n-doped conjugated polymers were achieved by doping the electron accepting PDNDIV and PFNDIVpolymers with ionic (TBACN) or neutral (TDAE) dopants. The great electron affinities, as indicated by the low LUMO levels of PDNDIV (−4.09 eV) and PFNDIV (−4.27 eV), facilitated the chemical reduction from either TBACN or TDAE. The low-lying LUMOs of the neutral polymers PDNDIV and PFNDIV were achieved by incorporation of vinylene spacers between the electron poor NDI units to increase the conjugation length without the use of an electron donor, and this was lowered further by an electron-withdrawing fluorinated N-substituent on the NDI moiety. The …


3' End Additions By T7 Rna Polymerase Are Rna Self-Templated, Distributive And Diverse In Character––Rna-Seq Analyses, Yasaman Gholamalipour, Aruni K. Mudiyanselage, Craig T. Martin Jan 2018

3' End Additions By T7 Rna Polymerase Are Rna Self-Templated, Distributive And Diverse In Character––Rna-Seq Analyses, Yasaman Gholamalipour, Aruni K. Mudiyanselage, Craig T. Martin

Chemistry Department Faculty Publication Series

Synthetic RNA is widely used in basic science, nanotechnology and therapeutics research. The vast majority of this RNA is synthesized in vitro by T7 RNA polymerase or one of its close family members. However, the desired RNA is generally contaminated with products longer and shorter than the DNA-encoded product. To better understand these undesired byproducts and the processes that generate them, we analyze in vitro transcription reactions using RNA-Seq as a tool. The results unambiguously confirm that product RNA rebinds to the polymerase and self-primes (in cis) generation of a hairpin duplex, a process that favorably competes with promoter driven …


High Energy Density In Azobenzene-Based Materials For Photo-Thermal Batteries Via Controlled Polymer Architecture And Polymer-Solvent Interactions, Seung Pyo Jeong, Lawrence A. Renna, Connor J. Boyle, Hyunwook S. Kwak, Edward Harder, Wolfgang Damm, Dhandapani Venkataraman Jan 2017

High Energy Density In Azobenzene-Based Materials For Photo-Thermal Batteries Via Controlled Polymer Architecture And Polymer-Solvent Interactions, Seung Pyo Jeong, Lawrence A. Renna, Connor J. Boyle, Hyunwook S. Kwak, Edward Harder, Wolfgang Damm, Dhandapani Venkataraman

Chemistry Department Faculty Publication Series

Energy densities of ~510 J/g (max: 698 J/g) have been achieved in azobenzene-based syndiotactic-rich poly(methacrylate) polymers. The processing solvent and polymer-solvent interactions are important to achieve morphologically optimal structures for high-energy density materials. This work shows that morphological changes of solid-state syndiotactic polymers, driven by different solvent processings play an important role in controlling the activation energy of Z-E isomerization as well as the shape of the DSC exotherm. Thus, this study shows the crucial role of processing solvents and thin film structure in achieving higher energy densities.


Comparative Study Of Multicellular Tumor Spheroid Formation Methods And Implications For Drug Screening, Maria F. Gencoglu, Lauren E. Barney, Christopher L. Hall, Elizabeth A. Brooks, Alyssa D. Schwartz, Daniel C. Corbett, Kelly R. Stevens, Shelly Peyton Jan 2017

Comparative Study Of Multicellular Tumor Spheroid Formation Methods And Implications For Drug Screening, Maria F. Gencoglu, Lauren E. Barney, Christopher L. Hall, Elizabeth A. Brooks, Alyssa D. Schwartz, Daniel C. Corbett, Kelly R. Stevens, Shelly Peyton

Chemical Engineering Faculty Publication Series

Improved in vitro models are needed to better understand cancer progression and bridge the gap between in vitro proof-of-concept studies, in vivo validation, and clinical application. Multicellular tumor spheroids (MCTS) are a popular method for three-dimensional (3D) cell culture, because they capture some aspects of the dimensionality, cell–cell contact, and cell–matrix interactions seen in vivo. Many approaches exist to create MCTS from cell lines, and they have been used to study tumor cell invasion, growth, and how cells respond to drugs in physiologically relevant 3D microenvironments. However, there are several discrepancies in the observations made of cell behaviors when comparing …


2016 Newsletter, Julian Tyson, Kevin Griffith Jan 2016

2016 Newsletter, Julian Tyson, Kevin Griffith

STEM Education Institute Newsletters

PVSTEMNet Update, Pg. 2

Arsenic Education, Pg. 3-6

UMass Biotech Initiatives, Pg. 7-8

BioTeach Program, Pg. 9

NSTA Award, Pg. 10

Cosmos Course, Pg.11

Humor and Climate, Pg. 12-13

More Cli-Sci Fiction, Pg. 14

Science and Engineering Saturday Seminars, Pg. 15-16

Tuesday Talks, Pg. 17-18


Carbon Nanotubes And Graphene As Additives In 3d Printing, Lara A. Al-Hariri, Branden Leonhardt, Mesopotamia Nowotarski, James Magi, Kaelynn Chambliss, Thaís Venzel, Sagar Delekar, Steve Acquah Jan 2016

Carbon Nanotubes And Graphene As Additives In 3d Printing, Lara A. Al-Hariri, Branden Leonhardt, Mesopotamia Nowotarski, James Magi, Kaelynn Chambliss, Thaís Venzel, Sagar Delekar, Steve Acquah

Chemistry Department Faculty Publication Series

3D printing is a revolutionary technology for the consumer and industrial markets. As the technology for 3D printing has expanded, the need for multi-materials that support fused deposition modeling and other forms of additive manufacturing is increasing. 3D printing filaments infused with carbon nanotubes and graphene are now commercially available, with the promise of producing conductive composites. This chapter explores some of the research, products, and challenges involved in bringing the next generation of functional printing materials to the consumer market.


Where To Buy Materials For The Activities, Morton Sternheim Jan 2015

Where To Buy Materials For The Activities, Morton Sternheim

Nanotechnology Teacher Summer Institutes

Sources for some of the less common materials used in the activities.


Nanotechnology Overview Powerpoint, Mark Tuominen Jan 2015

Nanotechnology Overview Powerpoint, Mark Tuominen

Nanotechnology Teacher Summer Institutes

Nanotechnology is the understanding and control of matter at dimensions of roughly 1 to 100 nanometers, where unique phenomena enable novel applications. This PowerPoint gives an overview of the field and introduces the teacher summer institute.


Gelatin Diffusion Experiment, Jennifer Welborn Jan 2015

Gelatin Diffusion Experiment, Jennifer Welborn

Nanotechnology Teacher Summer Institutes

In this activity, nanotech participants will:

- See how food dyes and gelatin are used to model the delivery of nanoscale medicines to cells in the human body - Measure diffusion distances of 3 different colors of food dye by: Eye, photo image on a computer, ADI software (Analyzing Digital Images) Some useful websites:


The Science Of Two Dimensional Materials (Powerpoint), Jun Yan Jan 2015

The Science Of Two Dimensional Materials (Powerpoint), Jun Yan

Nanotechnology Teacher Summer Institutes

Graphene is a single atomic sheet of graphite.

Exercise: how much graphene do we need to cover the surface of the empire state building?


Nanoscale Thin Films, Rob Snyder Jan 2015

Nanoscale Thin Films, Rob Snyder

Nanotechnology Teacher Summer Institutes

An activity that makes a nanoscale film of oleic acid on water. The student will

  • Learn about Ben Franklin’s observations of a thin film that had a nanoscale dimension.

  • Create a very thin film with a very dilute solution of oleic acid.

  • Use data you collect to determine if you made a thin film with a nanoscale dimension that formed on the surface of water.

  • Learn about the molecular interactions that resulted in the formation of the thin film.

  • Be introduced to the Big Ideas of Nanoscale Self-Assembly


Seeing At The Nanoscale: New Microscopies For The Life Sciences, Jennifer Ross Jan 2015

Seeing At The Nanoscale: New Microscopies For The Life Sciences, Jennifer Ross

Nanotechnology Teacher Summer Institutes

Visualizing single modules with fluorescence microscopy


Ozone, Uv, And Nanoparticles, Morton Sternheim, Jennifer Welborn Jan 2015

Ozone, Uv, And Nanoparticles, Morton Sternheim, Jennifer Welborn

Nanotechnology Teacher Summer Institutes

•Ultraviolet light causes skin damage and cancer •Ozone in the stratosphere blocks UV •Sunscreen blocks UV, partly •Nanoparticles in sunscreen improve blocking Sunscreen PowerPoint and activities based on NanoSense web site:

http://nanosense.sri.com/activities/clearsunscreen/index.html


Powers Of Ten: From Meters To Nanometers And Beyond, Rob Snyder Jan 2015

Powers Of Ten: From Meters To Nanometers And Beyond, Rob Snyder

Nanotechnology Teacher Summer Institutes

The goal of this activity is to guide students toward an understanding of nanoscale dimensions by:

  • Making a number of measurements using meter sticks, magnifiers, microscopes and spectrometers so students can make observations and generate their own data.

  • Using scientific notation to compare the measurements they have made with the dimensions of very small structures


Self Assembly, Mark Tuominem, Jennifer Welborn, Rob Snyder Jan 2015

Self Assembly, Mark Tuominem, Jennifer Welborn, Rob Snyder

Nanotechnology Teacher Summer Institutes

No abstract provided.


Nanomedicine, Mark Tuominen Jan 2015

Nanomedicine, Mark Tuominen

Nanotechnology Teacher Summer Institutes

An overview of nanomedicine. The end goal of nanomedicine is improved diagnostics, treatment and prevention of disease. Nanotechnology holds key to a number of recent and future breakthroughs in medicine.


Integrating Arsenic-Related Environmental Topics Into The Education Of The Next Generation Of Citizens For Arsenic-Hit Communities: Awareness And Mobilization, Julian Tyson Jan 2015

Integrating Arsenic-Related Environmental Topics Into The Education Of The Next Generation Of Citizens For Arsenic-Hit Communities: Awareness And Mobilization, Julian Tyson

Chemistry Department Faculty Publication Series

No abstract provided.


Immobilization Of Scandium And Other Chemical Elements In Systems With Aquatic Macrophyte, S. A. Ostroumov, M. E. Johnson, Julian Tyson, B. Xing Jan 2015

Immobilization Of Scandium And Other Chemical Elements In Systems With Aquatic Macrophyte, S. A. Ostroumov, M. E. Johnson, Julian Tyson, B. Xing

Chemistry Department Faculty Publication Series

No abstract provided.


Evaluation Report, Alan Peterfreund Jan 2014

Evaluation Report, Alan Peterfreund

STEM Digital

This evaluation report synthesizes the results of evaluation activities conducted by SageFox Consulting Group of the STEM DIGITAL project led by the UMass STEM Ed Institute for its no-cost extension year, covering the period September 2013 to August 2014. The goals of the program are to facilitate the participants’ abilities to stimulate student interest in STEM careers while engaging them in ways to think critically about their environment. Participating teachers incorporated digital cameras and Analyzing Digital Images (ADI) software into lab activities focusing on environmental science. STEM DIGITAL materials focused on three strands related to (1) ozone and air quality, …


Push-Pull Molecules: Models And Polymer Building Blocks For Organic Photovoltaic Applications, Raymond Devaughn Jan 2014

Push-Pull Molecules: Models And Polymer Building Blocks For Organic Photovoltaic Applications, Raymond Devaughn

Masters Theses 1911 - February 2014

Several fluorenone alkynyl based oligo conjugated molecules were synthesized and characterized. Most compounds exhibited UV-Vis absorption onset at ca. 500 nm and a PL emission onset of ~329-370 nm, with excimer emission suspected from most systems near ~530-560 nm. Experimentally determined EHOMO and ELUMO energies range from -6.02 to -5.73 eV and -3.47 and 3.55 eV, respectively, with the lowest experimental Eg lying at -2.26 eV for 2-(trimethoxyphenylacetylene)-fluorenone. Cyclic voltammetry indicates quasi-reversible reduction for all systems, with 2,7-bis(nitrophenylacetylene)fluorenone exhibiting a high reduction potential of -1.25 eV. Only 2,7-bis(trimethoxyphenylacetylene)fluorenone exhibited a quasi-reversible oxidation, due to electron rich methoxy …


2013-2014 Newsletter, Morton Sternheim Jan 2014

2013-2014 Newsletter, Morton Sternheim

STEM Education Institute Newsletters

Patterns Workshop

iCons

New! MassBioEd Seminars

Arsenic: Citizen Science

STEM DIGITAL online

Nanotechnology