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Biodegradable and Inherently Fluorescent pH-Responsive Nanoparticles for Cancer Drug Delivery
No full textPurpose: The development of two novel pH-only and pH- and thermo-responsive theranostic nanoparticle (NP) formulations to deliver an anticancer drug and track the accumulation and therapeutic efficacy of the formulations through inherent fluorescence. Methods: A pH-responsive formulation was synthesized from biodegradable photoluminescent polymer (BPLP) and sodium bicarbonate (SBC) via an emulsion technique, while a thermoresponsive BPLP copolymer (TFP) and SBC were used to synthesize a dual-stimuli responsive formulation via free radical co-polymerization. Cisplatin was employed as a model drug and encapsulated during synthesis. Size, surface charge, morphology, pH-dependent fluorescence, lower critical solution temperature (LCST; TFP NPs only), cytocompatibility and in vitro uptake, drug release kinetics and anticancer efficacy were assessed. Results: While all BPLP-SBC and TFP-SBC combinations produced spherical nanoparticles of a size between 200-300 nm, optimal polymer-SBC ratios were selected for further study. Of these, the optimal BPLP-SBC formulation was found to be cytocompatible against primary Type-1 alveolar epithelial cells (AT1) up to 100 μg/mL, and demonstrated sustained drug release over 14 days, dose-dependent uptake, and marked pH-dependent A549 cancer cell killing (72 vs. 24% cell viability, at pH 7.4 vs. 6.0). The optimal TFP-SBC formulation showed excellent cytocompatibility against AT1 cells up to 500 μg/mL, sustained release characteristics, dose-dependent uptake, pH-dependent (78% at pH 7.4 vs. 64% at pH 6.0 at 37°C) and marked temperature-dependent A549 cancer cell killing (64% at 37°C vs. 37% viability at pH 6.0, 41°C). Conclusions: In all, both formulations hold promise as inherently fluorescent, stimuli-responsive theranostic platforms for passively targeted anti-cancer therapy. Graphical Abstract: [Figure not available: see fulltext.]
Predicting Daily Stock Returns; A Lengthy Study of the Hong Kong and Japan Stock Exchanges
Get PDFIf stock markets are efficient then it should not be possible to predict stock returns, namely, no explanatory variable in a stock market regression model should be statistically significant. In this study, we find results indicating that daily effects exist in stock market returns. These daily or Calendar effects previously shown to exist by others clearly indicate the purpose of this study. Researchers often equate stock market efficiency with the non-predictability property of time series of stock returns. The purpose is to explore whether this line of argument is or is not satisfactory and does or does not aid in furthering our understanding of how markets operate. We focus on one definition of capital market efficiency and on the experience of these principles in analyzing the performance of the two large Asian Stock Market exchanges, which are Japan and Hong Kong. We observe that stock market returns (which include closing prices and dividends) are predictable and there are explanations for short-term predictability. Japan and Hong Kong were the focus of this study because of the maturity of their financial markets and the availability of clean data on these markets from a reputable and available resource. Furthermore, to reduce the influence of the Pandemic (2020-2022, the author studied a data base for a large number years prior to the era of the global Pandemic to reduce the argument that the era studed was a large enough sample and the influence of special variation associated variation associated with the unusual health period was reduce to nothing
Popular music media literacy: A pilot study
Get PDFThe current study pilot tested a popular music media literacy website that was developed based on the final report of the APA Division 46 Task Force on the Sexualization of Popular Music (2018). The study hypothesized that popular music media literacy education would produce significant differences between the baseline assessment and post-literacy assessment for outcomes related to music reflecting real life, viewing the self as similar to music portrayals, music skepticism, level of engagement with music, and self-reported self-esteem. It was also hypothesized that participants would report favorable attitudes regarding the popular music media literacy website being tested. Participants included 52 emerging adult college students who completed the baseline assessment and the post-literacy assessments after reviewing the popular music media literacy website. At baseline, participants reported moderate levels of music as reflecting real life, viewing themselves as similar to music representations and self-reported self-esteem. Participants also reported high levels of music skepticism and engagement with music at baseline. Results indicated that the popular music media literacy website was effective in increasing general music skepticism. The implications for future research and next directions are discussed
Approach to Estimate Hysteretic Soil Damping in Piled Jacket Structures
No full textThis paper presents a quasi-static empirical approach for estimating hysteretic damping of axially loaded piles in an offshore wind jacket structure. Damping is important because it can reduce fatigue in these structures, which may experience many millions of loading cycles. The proposed approach is developed within a \u27t-z\u27 analysis framework and based off modulus reduction and damping curves derived from dynamic element tests. A procedure and equations are provided to estimate the damping ratio through integration of the elastic strain energy density and dissipated energy density over the deformed soil mass. The relationship between damping and pile displacement, called a \u27D-z\u27 curve, is proposed for both discrete and lumped foundation models. Validation of the approach is still needed and research is ongoing
Quantification of microplastics in sediments from Narragansett Bay, Rhode Island USA using a novel isolation and extraction method
No full textMicroplastics are small plastic particles found ubiquitously in marine environments. In this study, a hybridized method was developed for the extraction of microplastics (45–1000 μm) from sediments using sodium bromide solution for density separation. Method development was tested using spiked microplastics as internal standards. The method was then used to extract microplastics from sediments in Narragansett Bay, Rhode Island, USA. Suspect microplastics were analyzed with Raman spectroscopy. Microplastic abundance ranged from 40 particles/100 g sediment to 4.6 million particles/100 g sediment (wet weight). Cellulose acetate fibers were the most abundant microplastic. These results are some of the first data for microplastics in Rhode Island sediments
Non-technical dimensions of communal wastewater treatment plant sustainability in peri-urban Yogyakarta, Indonesia
No full textBackground: This study focuses on identifying non-technical aspects that influence the sustainability of communal wastewater treatment plants (WWTPs) in a peri-urban area of Indonesia. Methods: A questionnaire survey was conducted by random sampling using a method of descriptive analysis that combines qualitative and quantitative approaches. Economic support for communal WWTPs was measured by the community’s Willingness to Pay (WTP) and Ability to Pay (ATP). Results: The results indicate that social dimension, such as a community’s level of participation are critically important in sustaining communal WWTPs. In addition, institutional dimension influences the degree of satisfaction a community has toward the WWTP management. This support is reinforced by social capital in the form of a philosophy of mutual cooperation, like gotong royong (cooperation by members of a community to achieve a common goal) and swadaya (self-reliance). Conclusions: The findings of this study can be used in Indonesia to make policy recommendations for managing and ensuring sustainability of communal WWTPs on a non-technical dimension. Additionally, gotong royong deserves to be promoted internationally as a fundamental value for fostering participation and contribution
Protein-Templated Core/Shell Au Nanostructures for Intracellular Reactive Oxygen Species Detection by SERS
No full textCore/shell gold raspberry nanostructures capable of multiple therapeutic functionalities were synthesized using a template composed of monodispersed anionic protein (bovine serum albumin) nanoparticles coated with a cationic biopolymer (poly-l-lysine). The nanostructures exhibited high photothermal conversion efficiency when exposed to a near-infrared (NIR) laser, which led to significant cellular inhibition of A549 human lung cancer cells due to intracellular hyperthermia. The raspberry structures also provided hot spots for surface-enhanced Raman scattering (SERS) ratiometric sensing of intracellular reactive oxygen species (ROS) when modified with the Raman reporter molecule 4-aminothiophenol (4-ATP). ROS was detected in A549 lung cancer cells upon photothermal heating of internalized nanostructures, enabling a possible mechanism for feedback on therapeutic efficacy. This was confirmed by adding the antioxidant N-acetylcysteine (NAC) and using a complementary fluorescence technique, which showed that the amount of detectable intracellular ROS decreased. These safe-by-design gold raspberry nanostructures could be promising for simultaneous therapeutic applications and monitoring therapeutic efficacy
Responsive Telechelic Block Copolymers for Enhancing the Elasticity of Nanoemulsions
No full textThe rheology of emulsions dictates their performance in many scientific and industrial applications. Here, we demonstrate that high-molecular-weight telechelic triblock copolymers composed of polystyrene end blocks with a poly(ethylene oxide) midblock effectively modify the rheology of a suspension of cyclohexane nanodroplets. Because of their telechelic structure, these polymers bridge between droplets to generate elastic networks with shear moduli on the order of 1000 Pa. The network elasticity increases with polymer concentration and molecular weight as the polymers more effectively form bridges. Furthermore, we tune the nanoscale interactions that control the polymer partitioning by decreasing the temperature below the cloud point of the system. At low temperatures, the polystyrene end blocks no longer preferentially partition into the cyclohexane droplets, and the emulsions begin to exhibit terminal viscous relaxations. These results identify key properties of telechelic block copolymers that can be exploited to significantly enhance nanoemulsion elasticity to improve the processability and transport of complex fluids in applications ranging from 3D printing to functional hydrogels
Conservative conservationists: reconciling conflicting identities on climate change
Get PDFIdentities – how individuals think about themselves in the social world – are powerful drivers of political attitudes and behaviors. On highly polarizing issues such as climate change, political identities are powerful predictors of attitudes, behaviors, and policy preferences. However, other, non-partisan identities are also relevant to climate change attitudes, particularly when the identity is threatened by climate change. What happens when an individual has two salient identities informing opposing attitudes on a political issue? This study leverages a unique sample of politically conservative members of an environmental conservation organization – “conservative conservationists” – to understand how people reconcile conflicting identities to form their environmental attitudes and behaviors. Using qualitative data from interviews (n = 25) and participant observation, I document four strategies that participants use to reconcile identity conflicts and form environmental attitudes: distancing oneself from one of the conflicting identities; increasing deliberate political information seeking; redefining conceptions of an issue to fit with both identities; and creating a new identity that merges the non-conflicting aspects of the two identities. This research has implications for both the theoretical study of how identities influence political behavior and practical efforts to build bipartisan agreement on climate change
Tobacco smoking changes during the first pre-vaccination phases of the COVID-19 pandemic: A systematic review and meta-analysis
Get PDFBackground:
Globally, tobacco smoking remains the largest preventable cause of premature death. The COVID-19 pandemic has forced nations to take unprecedented measures, including ‘lockdowns’ that might impact tobacco smoking behaviour. We performed a systematic review and meta-analyses to assess smoking behaviour changes during the early pre-vaccination phases of the COVID-19 pandemic in 2020.
Methods:
We searched Medline/Embase/PsycINFO/BioRxiv/MedRxiv/SSRN databases (January–November 2020) for published and pre-print articles that reported specific smoking behaviour changes or intentions after the onset of the COVID-19 pandemic. We used random-effects models to pool prevalence ratios comparing the prevalence of smoking during and before the pandemic, and the prevalence of smoking behaviour changes during the pandemic. The PROSPERO registration number for this systematic review was CRD42020206383.
Findings:
31 studies were included in meta-analyses, with smoking data for 269,164 participants across 24 countries. The proportion of people smoking during the pandemic was lower than that before, with a pooled prevalence ratio of 0·87 (95%CI:0·79–0·97). Among people who smoke, 21% (95%CI:14–30%) smoked less, 27% (95%CI:22–32%) smoked more, 50% (95%CI:41%-58%) had unchanged smoking and 4% (95%CI:1–9%) reported quitting smoking. Among people who did not smoke, 2% (95%CI:1–3%) started smoking during the pandemic. Heterogeneity was high in all meta-analyses and so the pooled estimates should be interpreted with caution (I2\u3e91% and p-heterogeneity\u3c0·001). Almost all studies were at high risk of bias due to use of non-representative samples, non-response bias, and utilisation of non-validated questions.
Interpretation:
Smoking behaviour changes during the first phases of the COVID-19 pandemic in 2020 were highly mixed. Meta-analyses indicated that there was a relative reduction in overall smoking prevalence during the pandemic, while similar proportions of people who smoke smoked more or smoked less, although heterogeneity was high. Implementation of evidence-based tobacco control policies and programs, including tobacco cessation services, have an important role in ensuring that the COVID-19 pandemic does not exacerbate the smoking pandemic and associated adverse health outcomes