Photodynamic therapy (PDT) has emerged as a promising targeted treatment for cancer. However, current PDT is limited by low tissue penetration, insufficient phototoxicity (toxicity with light irradiation), and undesirable cytotoxicity (toxicity without light irradiation). Here, we report the discovery of cyanine-carborane salts as potent photosensitizers (PSs) that harness the near-infrared (NIR) absorbing [cyanine+] with the inertness of [carborane-]. The implementation of [cyanine+] [carborane-] salts dramatically enhance cancer targeting of the PSs and decrease cytotoxicity. We characterize the cellular uptake of the cyanine-carborane PSs, organelle localization, generation of reactive oxygen species (ROS) with the ability to cogenerate multiple ROS species, suppression of pro-metastatic pathways, and activation of apoptotic pathways. We further demonstrate the ability of optimized PSs to eliminate tumors in vivo using an orthotopic mouse model of breast cancer. These newly developed [cyanine+] [carborane-] salt PSs introduce a potent therapeutic approach against aggressive breast cancer while decreasing side effects.

Organic luminophores offer great potential for energy harvesting and light emission due to tunable spectral properties, strong luminescence, high solubility, and excellent wavelength selectivity. To realize their full potential, the lifetimes of luminophores must extend to many years under illumination. Many organic luminophores, however, have a tendency to degrade and undergo rapid photobleaching, leading to the perception of intrinsic instability of organic molecules. In this work, we demonstrate that by exchanging the counterion of a heptamethine cyanine salt the photostability and corresponding lifetime of dilute cyanine salts can be enhanced by orders of magnitude from 10 h to an extrapolated lifetime of greater than 65,000 h under illumination. To help correlate and comprehend the underlying mechanism behind this phenomenon, the water contact angle and binding energy of each pairing were measured and calculated. We find that increased water contact angle, and therefore increasing hydrophobicity, generally correlates to improved lifetimes. Similarly, a lower absolute binding energy between cation and anion correlates to increased lifetimes. Utilizing the binding energy formalism, we predict the stability of a new anion and experimentally verify it with good consistency. Moving forward, these factors could be used to rapidly screen and identify highly photostable organic luminophore salt systems for a range of energy harvesting and light-emitting applications.

When learning to code, children and novice programmers often transition from block-based to traditional text-based programming environments. This paper explores the usability problems within a block-based authoring environment, EduBlocks, that may hinder children’s learning. Using domain-specific heuristics, a usability evaluation was performed by expert evaluators, which was later combined with data from an analysis of problems reported in Forums, to produce a corpus of usability problems. The corpus was subsequently analysed using thematic analysis, and seven design guidelines were synthesized. Using the guidelines, a model of interaction was created to inform the design of block-based authoring environments that support the transition to text-based authoring. The model examines the interplay between learning within a school environment to independently using the authoring environment and how the interface can support these differing scenarios. This paper contributes to the design of effective user interfaces to support children learning to code and provides guidelines for developers of hybrid authoring environments to support the transition away from blocks.

Transparent and semitransparent photovoltaics offer an exciting opportunity to integrate existing infrastructure with renewable energy. Organic photovoltaics (OPVs) are key enablers for wavelength‐selective transparent photovoltaics (TPVs) because of their selective absorption in the near‐infrared (NIR) that enables simultaneously high power conversion efficiency (PCE) and average visible transmittance (AVT). The recent rise of OPVs and TPVs has been accelerated in large part by the development of nonfullerene acceptors (NFAs) as highly adaptable deep NIR harvesting materials. Herein, sequential layer‐by‐layer (LBL) deposition of a selectively NIR absorbing nontraditional acceptor polymer is paired with a NIR absorbing donor IEICO‐4F that is typically considered an NFA via solvent orthogonality. With detailed optimization of the active layers and top electrode, semi‐transparent photovoltaics with a PCE of 8.8%, AVT of 40.9%, and a light utilization efficiency of 3.6% are demonstrated. The LBL approach enables explicit optical modeling of the device structure to extract exciton diffusion lengths >100 nm for both the polymer and IEICO‐4F with a transition in charge collection length regimes dependent on the acceptor thickness. Furthermore, the LBL deposition technique enables an investigation of the full range of polymer thickness and its impact on power generation and optical performance.

Photodynamic therapy (PDT) is currently limited by the inability of photosensitizers (PSs) to enter cancer cells and generate sufficient reactive oxygen species. Utilizing phosphorescent triplet states of novel PSs to generate singlet oxygen offers exciting possibilities for PDT. Here, we report phosphorescent octahedral molybdenum (Mo)-based nanoclusters (NC) with tunable toxicity for PDT of cancer cells without use of rare or toxic elements. Upon irradiation with blue light, these molecules are excited to their singlet state and then undergo intersystem crossing to their triplet state. These NCs display surprising tunability between their cellular cytotoxicity and phototoxicity by modulating the apical halide ligand with a series of short chain fatty acids from trifluoroacetate to heptafluorobutyrate. The NCs are effective in PDT against breast, skin, pancreas, and colon cancer cells as well as their highly metastatic derivatives, demonstrating the robustness of these NCs in treating a wide variety of aggressive cancer cells. Furthermore, these NCs are internalized by cancer cells, remain in the lysosome, and can be modulated by the apical ligand to produce singlet oxygen. Thus, (Mo)-based nanoclusters are an excellent platform for optimizing PSs. Our results highlight the profound impact of molecular nanocluster chemistry in PDT applications.

Fair and meaningful device performance comparison among luminescent solar concentrator-photovoltaic (LSC-PV) reports cannot be realized without a general consensus on reporting standards in LSC-PV research. Therefore, it is imperative to adopt standardized characterization protocols for these emerging types of PV devices that are consistent with other PV devices. This commentary highlights several common limitations in LSC literature and summarizes the best practices moving forward to harmonize with standard PV reporting, considering the greater nuances present with LSC-PV. Based on these practices, a checklist of actionable items is provided to help standardize the characterization/reporting protocols and offer a set of baseline expectations for authors, reviewers, and editors. The general consensus combined with the checklist will ultimately guide LSC-PV research towards reliable and meaningful advances.

Communication and teamwork are skills underpinned by a person's ability to perceive, interpret and understand another's emotional state, and respond in an appropriate manner. Children, adolescents and young adults with Autism Spectrum Disorder (ASD) struggle with these "emotion recognition skills", often impairing their ability to communicate effectively. A range of interventions have been created and studied, yielding mixed results. Some of these interventions utilise elements of Paul Ekman's research into expression of emotion. This paper reviews and discusses several of these studies, considers the technical problems in each, and proposes a future framework for continued development in this field.

Photodynamic therapy (PDT) has the potential to improve cancer treatment by providing dual selectivity through the use of both photoactive agent and light, with the goal of minimal harmful effects from either the agent or light alone. However, current PDT is limited by insufficient photosensitizers (PSs) that can suffer from low tissue penetration, insufficient phototoxicity (toxicity with light irradiation), or undesirable cytotoxicity (toxicity without light irradiation). Recently, we reported a platform for decoupling optical and electronic properties with counterions that modulate frontier molecular orbital levels of a photoactive ion. Here, we demonstrate the utility of this platform in vivo by pairing near-infrared (NIR) photoactive heptamethine cyanine cation (Cy+), which has enhanced optical properties for deep tissue penetration, with counterions that make it cytotoxic, phototoxic, or nontoxic in a mouse model of breast cancer. We find that pairing Cy+ with weakly coordinating anion FPhB- results in a selectively phototoxic PS (CyFPhB) that stops tumor growth in vivo with minimal side effects. This work provides proof of concept that our counterion pairing platform can be used to generate improved cancer PSs that are selectively phototoxic to tumors and nontoxic to normal healthy tissues.

Small bandgap organic compounds with absorption in the near-infrared are exciting materials for a variety of applications ranging from light harvesters in photovoltaics to active agents in photodynamic therapy. Organic salts, a class of small molecule organic compounds comprised of an ionic chromophore and a counterion, have been used in opaque and transparent photovoltaics, primarily as donor materials in bilayer architectures. They possess excellent molecular extinction coefficients with near-infrared selective absorption, adjustable bandgaps, and tunable energy levels. To approach organic salt photovoltaics from a new perspective, we fabricated devices with an unexplored group of anionic salts comprised of a near-infrared absorbing chromophore paired with a varying number of cationic counterions. We observed different donor and acceptor decay trends in external quantum efficiencies that allowed us to separate and independently quantify exciton diffusion and charge transfer for each salt. Increased charge character on the chromophore greatly improves hole transport, as anions with a net −3 charge have charge collection lengths greater than four times those of corresponding singly charged chromophores. This presents an interesting platform for independent quantification of exciton diffusion and charge transport of an active material in a single photovoltaic device and demonstration of the important role of charge on the chromophore. The dependence of charge transport capabilities on charge character of the chromophore will be a useful tool in the design of future organic salts to engineer materials for higher efficiency transparent photovoltaics.

BACKGROUND:The normal healing of surgical wounds can be disrupted by infection and/or dehiscence, leading to development of chronic, non-healing wounds (NHW). Diagnosis of NHWs is via clinical acumen and analysis of microbiology wound swabs. Volatile organic compounds (VOCs) are emitted generally by human subjects and specifically as products of bacterial metabolism and are detected in the wound area. This systematic review will assess the potential use of VOCs released by surgical wounds as a non-invasive method for identifying bacterial species and the progression to NHW. METHOD:A systematic search of studies, via PRISMA guidelines, was conducted. Of 220 papers screened, seven studies were included. Outcome data were extracted on methods for VOC analysis and wound/bacterial VOC profiles. RESULTS:The studies have shown that VOC profiles are identified by two methods: gas chromatography-mass spectrometry and electronic nose. There are VOC profiles associated with causative bacterial species, with early indications that they could be anatomically specific or could monitor treatment effects. CONCLUSION:VOC profiling of bacterial species within wounds is possible and could become a point of care test. More research is needed on specific VOC profiles to wound location and whether these profiles may predict progression to NHW.

Visibly transparent luminescent solar concentrators (TLSCs) can optimize both power production and visible transparency by selectively harvesting the invisible portion of the solar spectrum. Since the primary applications of TLSCs include building envelopes, greenhouses, automobiles, signage, and mobile electronics, maintaining aesthetics and functionalities is as important as achieving high power conversion efficiencies (PCEs) in practical deployment. In this work, we combine massive-downshifting phosphorescent nanoclusters and fluorescent organic molecules into a TLSC system as ultraviolet (UV) and near-infrared (NIR) selective-harvesting luminophores, respectively, demonstrating UV and NIR dual-band selective-harvesting TLSCs with PCE over 3%, average visible transmittance (AVT) exceeding 75% and color metrics suitable for the window industry. With distinct wavelength-selectivity and effective utilization of the invisible portion of the solar spectrum, this work reports the highest light utilization efficiency (PCE x AVT) of 2.6 for a TLSC system, the highest PCE of any transparent photovoltaic device with AVT greater than 70%, and outperforms the practical limit for non-wavelength-selective transparent photovoltaics.

Visual programming tools allow users to create interactive media projects such as games and animations using visual representations of programming concepts. Although these tools have been shown to have huge potential for teaching children, research has shown that they may not be accessible for children with cognitive impairments, including those with autism spectrum condition. Therefore, this study proposes a set of recommendations for the design of accessible visual programming tools for children with autism spectrum condition. Semi-structured interviews with experts (n = 7) were conducted and thematically analysed to identify initial recommendations. A second set of semi-structured interviews with a subset of the initial experts (n = 3) were then conducted to validate and produce a final set of recommendations.

Transparent luminescent solar concentrators (TLSCs) selectively harvest ultraviolet and near-infrared photons. Due to the absence of electrodes, busbars, and collection grids over the solar harvesting area, the device structure enables these devices to achieve the highest levels of transparency and aesthetics. Recently, CO(i)8DFIC has been developed as a nonfullerene acceptor in organic photovoltaics with unprecedented performance. In this work, nonfullerene acceptors are introduced into TLSCs as the luminophores. The impact of CO(i)8DFIC concentration on power conversion efficiency (PCE), aesthetic quality, and scalability is systematically studied. After device optimization, the CO(i)8DFIC TLSCs are shown to achieve a PCE over 1.2% while the average visible transmittance exceeds 74% and color rendering index exceeds 80. This work reports the highest TLSC device efficiency at the highest visibly transparency and highlights that the photoluminescent properties of these emerging low bandgap organic molecules providing an encouraging path to higher TLSC performance.

Motivated by the exciting properties of metal halide perovskites in photovoltaic applications, there is an evolving need to further explore the limitations of this class of materials in broader fields and high end optoelectronics, which requires better control over the film structure, defect levels, and quality. Epitaxial growth has been ubiquitously deployed in the semiconducting industry. This affords routes to precisely align the atomic arrangement to control the structure and strain and achieve the highest levels of optoelectronic performance. In this review, the recent emergence and progress in the epitaxial growth of metal halide perovskites are introduced within the context of epitaxial and quasiepitaxial approaches, and recent advances are surveyed from growth methods to application integration. The main criteria distinguishing epitaxy and quasiepitaxy, i.e., lattice matching and ordering, can be deployed to direct the selection of proper substrates, growth methods, and precursors for various applications.

Visual programming tools provide a visual programming and execution environment in addition to other visual resources and tools appropriate for creating visual programs for a particular domain. Several visual programming tools have been created for teaching children to program at an early age such as Scratch, ScratchJr, Pocket Code, Code.org and Kodu. Research on the use and benefits of these tools as aids for children to learn academic and non-academic skills has reported positive results. However, children with learning disabilities including those also diagnosed with autism spectrum condition are left out of this area of research. This paper builds on a previous study on the accessibility of Scratch by inspecting other existing visual programming tools targeted at children to determine whether they have features that mitigate accessibility difficulties similar to those that were identified in Scratch. The paper contributes to knowledge by providing an insight into the features of popular VPTs that are likely to cause difficulties for children with learning disabilities and autism spectrum condition.

Purpose Personae are simple tools for describing users, their characteristics and their goals. They are valuable tools when designing for a specific group of users, such as children with autism spectrum condition (ASC). The purpose of this paper is to propose, validate and revise a methodology for creating accurate, data grounded personae for children with ASC. Design/methodology/approach The proposed method is based mainly on Cooper et al.'s (2007) persona construction method. It proposes gathering and analysing qualitative data from users and experts to either create a new persona or extend an existing one. The method is then applied to create personae for the design of a visual programming tool for children with ASC. Based on the results of the application, observations and lessons learnt, a revised version of the method is proposed. Findings The method's combined use of user data and expert knowledge produced a set of personae that have been well reviewed by experts so far. The method's use of a questionnaire to validate personae also produced relevant qualitative feedback. On review, possible downsides of extending existing personae were identified. Therefore, a revised method was introduced, eliminating the need to extend existing personae, and stressing the importance of utilising user data, expert knowledge and feedback. Originality/value This paper addresses the need for a well-defined method for creating data grounded personae that accurately describe the characteristics and goals of children with ASC. Such personae can be used to design and develop more accessible and usable products.

Chenchen Yang joined the materials science program at Michigan State University in 2015 to work under Prof. Lunt in the Molecular and Organic Excitonics Lab. He earned his B.E. from the University of Electronic Science and Engineering of China in 2012. Then, he obtained his M.S. from University of Florida in 2015. His current research focuses on transparent solar cell synthesis, fabrication, and characterization.Dianyi Liu obtained his PhD in inorganic chemistry from Lanzhou University in 2009. He then worked as a postdoc at Peking University, the University of Saskatchewan, and Michigan State University. He began as an assistant professor at Westlake University in January 2019. His research interests include flexible electronics, optoelectronic materials, and devices.Matthew Bates is a graduate student in chemical engineering at Michigan State University working in the Molecular and Organic Excitonic Lab led by Prof. Lunt. He received his B.S. in chemical engineering from Oregon State University in 2016. He is focused on developing transparent photovoltaics.Miles Barr is co-founder and Chief Technology Officer at Ubiquitous Energy in Redwood City, CA. He earned his bachelor’s degree from Vanderbilt University and his Ph.D. from the Massachusetts Institute of Technology, both in chemical engineering. He then co-founded Ubiquitous Energy and has grown the company through pilot manufacturing, serving as both CEO and CTO. His team is currently working to develop, scale up, and commercialize transparent solar technology for a variety of end applications.Richard R. Lunt is the Johansen Crosby Endowed Professor at Michigan State University in the Departments of Chemical Engineering & Materials Science and Physics. He earned his B.S. from the University of Delaware and his PhD from Princeton University. He then worked as a post-doctoral researcher at MIT. His group focuses on understanding and exploiting excitonic photophysics and molecular crystal growth to develop unique thin-film optoelectronic devices. He is known for his pioneering work on transparent solar cells. Chenchen Yang joined the materials science program at Michigan State University in 2015 to work under Prof. Lunt in the Molecular and Organic Excitonics Lab. He earned his B.E. from the University of Electronic Science and Engineering of China in 2012. Then, he obtained his M.S. from University of Florida in 2015. His current research focuses on transparent solar cell synthesis, fabrication, and characterization. Dianyi Liu obtained his PhD in inorganic chemistry from Lanzhou University in 2009. He then worked as a postdoc at Peking University, the University of Saskatchewan, and Michigan State University. He began as an assistant professor at Westlake University in January 2019. His research interests include flexible electronics, optoelectronic materials, and devices. Matthew Bates is a graduate student in chemical engineering at Michigan State University working in the Molecular and Organic Excitonic Lab led by Prof. Lunt. He received his B.S. in chemical engineering from Oregon State University in 2016. He is focused on developing transparent photovoltaics. Miles Barr is co-founder and Chief Technology Officer at Ubiquitous Energy in Redwood City, CA. He earned his bachelor’s degree from Vanderbilt University and his Ph.D. from the Massachusetts Institute of Technology, both in chemical engineering. He then co-founded Ubiquitous Energy and has grown the company through pilot manufacturing, serving as both CEO and CTO. His team is currently working to develop, scale up, and commercialize transparent solar technology for a variety of end applications. Richard R. Lunt is the Johansen Crosby Endowed Professor at Michigan State University in the Departments of Chemical Engineering & Materials Science and Physics. He earned his B.S. from the University of Delaware and his PhD from Princeton University. He then worked as a post-doctoral researcher at MIT. His group focuses on understanding and exploiting excitonic photophysics and molecular crystal growth to develop unique thin-film optoelectronic devices. He is known for his pioneering work on transparent solar cells.

This technical note (TN) describes how environmental life-cycle assessment (LCA) can integrate multiple environmental considerations and stakeholder constraints to inform and support sustainable operations and best practices for the U.S.

Light-activated theranostics offer promising opportunities for disease diagnosis, image-guided surgery, and site-specific personalized therapy. However, current fluorescent dyes are limited by low brightness, high cytotoxicity, poor tissue penetration, and unwanted side effects. To overcome these limitations, we demonstrate a platform for optoelectronic tuning, which allows independent control of the optical properties from the electronic properties of fluorescent organic salts. This is achieved through cationanion pairing of organic salts that can modulate the frontier molecular orbital without impacting the bandgap. Optoelectronic tuning enables decoupled control over the cytotoxicity and phototoxicity of fluorescent organic salts by selective generation of mitochondrial reactive oxygen species that control cell viability. We show that through counterion pairing, organic salt nanoparticles can be tuned to be either nontoxic for enhanced imaging, or phototoxic for improved photodynamic therapy.