A 700 nm LED Light Activated Ru(II) Complex Destroys Tumor Cytoskeleton via Photosensitization and Photocatalysis.

Photoactivable chemotherapy (PACT) using metallic complexes provides spatiotemporal selectivity over drug activation for targeted anticancer therapy. However, the poor absorption in near-infrared (NIR) light region of most metallic complexes renders tissue penetration challenging. Herein, an NIR light triggered dinuclear photoactivable Ru(II) complex (Ru2) is presented and the antitumor mechanism is comprehensively investigated. The introduction of a donor-acceptor-donor (D-A-D) linker greatly enhances the intramolecular charge transition, resulting in a high molar extinction coefficient in the NIR region with an extended triplet excited state lifetime. Most importantly, when activated by 700 nm NIR light, Ru2 exhibits unique slow photodissociation kinetics that facilitates synergistic photosensitization and photocatalytic activity to destroy diverse intracellular biomolecules. In vitro and in vivo experiments show that when activated by 700 nm NIR light, Ru2 exhibits nanomolar photocytotoxicity toward 4T1 cancer cells via the induction of calcium overload and endoplasmic reticulum (ER) stress. These findings provide a robust foundation for the development of NIR-activated Ru(II) PACT complexes for phototherapeutic application.

Novel photoactivated Indole-pyridine chemotherapeutics with strong antimicrobial and antibiofilm activity toward Staphylococcus aureus.

The challenge of antibiotic resistance worldwide has brought an urgent need to explore novel drugs for bacterial infections. Antimicrobial photodynamic therapy has been proven to be a potential antimicrobial modality but is limited by biofilms. In this study, we synthesized three cationic photosensitizers with strong photoinduced antimicrobial and antibiofilm activities toward gram-positive Staphylococcus aureus. The indole-pyridine compounds illustrated multiple type I/II photosensitization and coenzyme NAD(P)H photocatalytic activity upon excitation. A mechanistic study showed that intracellular reactive oxygen generation and NAD(P)H oxidation caused membrane damage, leading to protein/nucleus acid leakage. This research provides insights into the development of novel chemotherapeutics with synergetic photodynamic and photocatalytic reactivity.

Novel Ru(II) complexes with multiple anticancer photoreactivity: ligand exchange, photoredox catalysis, reactive oxygen generation and endoperoxide formation.

The hypoxic microenvironment and drug resistance of cancer cells have become a huge threat for clinical anticancer therapy. Anticancer phototherapy providing spatial and temporal control over drug activation may conquer this problem. Herein, we report a novel photoactivated Ru(II) complex (Ru2) with multiple activities including photochemotherapy, photodynamic and photocatalytic therapy, and endoperoxide formation. Upon white light irradiation, Ru2 can dissociate the coordinating ligands and form endoperoxides, produce diverse reactive oxygen species and catalytically oxidize cellular coenzymes. As a result, Ru2 shows promising antiproliferation activity toward cisplatin and 5-fluorouracil resistant tumor cell lines under normoxia and hypoxia. The multifunctional design strategy of metal-based anticancer drugs offers novel efficient therapeutics to combat drug-resistant cancer cells under hypoxia.

Physical health caregiver, mental wellness supporter, and overall well-being advocate: Women's roles towards animal welfare during the COVID-19 emergency response.

Women's health-specific contributions in emergency response stages pertain primarily to family and community-based rescue and support-focused roles. As disasters affect both human beings and their animal co-inhabitants, comprehensive literature exploring women's contributions towards companion animal welfare in emergency response settings remains sparse. COVID-19-triggered public health mitigation strategies caused diverse challenges relating to veterinary medical service access, thus establishing a platform for a nuanced exploration of gendered roles vis-a-vis animal health and well-being during the initial COVID-19 emergency response period. This project employs a semi-structured interview approach to qualitatively investigate the roles, responsibilities, and experiences of twelve people, eleven of whom self-identify as women, who cared for animal co-inhabitants while seeking veterinary medical services during the COVID-19 emergency response in Metro Vancouver, British Columbia, Canada. This research identifies three primary animal welfare-related roles that woman companion animal guardians (WCAGs) assumed during the COVID-19 emergency response period: 1) Companion animal physical health caregiver, spanning from nuclear to extended families and into the community; 2) Companion animal mental wellness supporter, associated with human-animal interactions in family/household, community, and veterinary clinic settings; 3) Companion animal holistic well-being advocate, utilizing various strategies at family, community, and societal levels. Understanding gender-specific animal welfare contributions in an emergency response setting narrows knowledge gaps and provides WCAGs and animal welfare-related public, private, and not-for-profit sectors with evidence-based strategies for emergency response planning improvements, supporting healthy and sustainable human-animal bonds in the current COVID-19 pandemic and future extreme events.

Building Emergency Response Capacity: Multi-Career-Stage Social Workers' Engagement with Homeless Sector during the First Two Waves of COVID-19 in Halifax, Nova Scotia, Canada.

The dramatic increase of global extreme events (e.g., natural, technological, and willful hazards) propels social workers to be equipped with emergency response capacity, supporting affected individuals, families, and communities to prepare, respond, and recover from disasters. Although social workers have historically been engaged in emergency response, social work curriculum and professional training remain slow to adapt, jeopardizing their capacity to support the vulnerable and marginalized populations, who have always been disproportionately affected by extreme events. In response to this deficit, this article utilizes a critical reflection approach to examine three social workers' (a senior faculty, a junior faculty, and a social work student) interventions and challenges in their emergency response to persons experiencing homelessness (PEHs) during the first two waves of COVID-19 in Halifax, Nova Scotia, Canada (March 2020 to March 2021). The cross-career-stage reflections and analyses exhibit these three social workers' COVID-19-specific emergency response efforts: a top-down advocacy effort for social development and policy, a bottom-up cognitive effort to comprehend the community's dynamics, and a disaster-driven self-care effort. These three types of effort demonstrate a greater need for social work education and professional training, to develop more disaster-specific components to contribute to building the emergency response capacity of the next generation of social workers through in-classroom pedagogical enhancement and on-site field education training, better supporting PEHs and other vulnerable and marginalized groups living in the diverse context of extreme events in Canada and internationally.

Adaptability, Interdisciplinarity, Engageability: Critical Reflections on Green Social Work Teaching and Training.

The upward tendencies of global climate change, disasters, and other diverse crises have been urgently calling for green social work (GSW) interventions which engage a holistic approach to explore diverse societal dimensions' compounded influences on inhabitants' individual and collective health and well-being in disaster settings. Though globally gaining more attention, GSW has been slow to develop in the Canadian social work curriculum and professional training. This deficit jeopardizes integrating environmental and climate justice and sustainability in social work research and practice in Canada. In response to this pedagogical inadequacy, this article employs a critical reflection approach to examine two authors' two-academic-year teaching-learning and supervision-training experiences of GSW-specific in-class and field education in a Master of Social Work program. The content analysis illustrates three essential components for GSW-specific teaching and training, namely adaptability, interdisciplinarity, and engageability. These components enhance the prospective social workers' micro-, mezzo-, and macro-level practices to better support individuals, families, and communities affected by extreme events and promote their health and well-being in disaster and non-disaster scenarios. These GSW-specific pedagogies shed light on the fact that integrading climate change, disasters, and diverse crises in pedagogical innovations should be encouraged beyond the social work profession. A multidisciplinary multi-stakeholder engagement approach would comprehensively investigate and evaluate the essential components and evidence-based strategies that better serve inhabitants and promote resilience and sustainability.

Mass email risk communication: Lessons learned from COVID-19-triggered campus-wide evictions in Canada and the United States.

From an out-of-province/state and international post-secondary student perspective, this article (a) explores mass email risk communication facilitation during the COVID-19-triggered campus-wide evictions in Canada and the United States; and (b) develops relative recommendations to improve mass email risk communication strategies for future emergency response. Investigating mass email risk communication-related impacts on students in a tertiary educational context has revealed a significant deficit in emergency response research, practice, and policymaking. Mandatory temporary university and college closures during the COVID-19 first wave provided an opportunity to address this research and practice deficit, as most Canadian and American universities/colleges administered their eviction communication via daily mass email chains. Through a phenomenological lens, this study interviewed twenty out-of-province/state and international students, ten from each country respectively, to examine student eviction experiences associated with intensive mass email risk communication. This research identified four factors linked to mass email risk communication: email chain characteristics, student interpretation, interdepartmental cooperation, and frontline voices. Synthesizing these findings, four evidence-based recommendations were developed: to efficiently convey risk information to students, to understand student perceptions and to inform their behaviors, to enhance interdepartmental cooperation, and to enable mutual dialogue in decision making. These recommendations could assist post-secondary institutions, and other organizations, in strengthening their mass email risk communication strategies and advancing organizational emergency response plans for future extreme events.

Barriers to Care in Veterinary Services: Lessons Learned From Low-Income Pet Guardians' Experiences at Private Clinics and Hospitals During COVID-19.

This qualitative study aimed to explore the experiences of low-income pet guardians in accessing veterinary care during COVID-19. Participants were recruited through a purposive sampling method: 12 individuals who applied to and met the low-income threshold to access support for veterinary fees from the Vancouver Humane Society (VHS) were invited for semi-structured in-depth telephone interviews. Participants indicated that they experienced pandemic-related barriers related to and compounded by their low-income status. Their experiences fit into three categories: the barriers to accessing veterinary care pre-and peri-COVID-19, the emotional impact of compounding barriers related to accessing veterinary care during COVID-19, and the human-animal bond and resilience in the context of COVID-19. Drawing on the One Health, One Welfare approach, we argue that veterinary and animal services should evaluate and improve their support services, particularly programs developed for low-income pet guardians. Based on the participants' recommendations, we propose that veterinary and animal services prepare for future disaster situations by increasing their financial capacity to support people needing assistance, undergoing training to better work with people experiencing financial and emotional stress, and providing easily accessible resources to better distribute knowledge about animal needs and available financial assistance programming. The suggestions are intended to benefit animals, their guardians, and both veterinary and animal service sector workers.

Dual-Gendered Leadership: Gender-Inclusive Scientific-Political Public Health Communication Supporting Government COVID-19 Responses in Atlantic Canada.

This research aims to identify the influence of woman leadership on improving the traditional man-dominated scientific-political communication towards positive COVID-19-driven public health interventions. Across Canada, dual-gendered leadership (women chief medical officers and men prime minister/premiers) at both federal and provincial levels illustrated a positive approach to "flatten the curve" during the first and second waves of COVID-19. With the four provinces of New Brunswick, Newfoundland and Labrador, Nova Scotia, and Prince Edward Island, Atlantic Canada formed the "Atlantic Bubble", which has become a great example domestically and internationally of successfully mitigating the pandemic while maintaining societal operation. Three provinces have benefitted from this complementary dual-gendered leadership. This case study utilized a scoping media coverage review approach, quantitatively examining how gender-inclusive scientific-political cooperation supported effective provincial responses in Atlantic Canada during the first two waves of COVID-19. This case study discovers that (1) at the provincial government level, woman leadership of mitigation, advocating, and coordination encouraged provincial authorities to adapt science-based interventions and deliver consistent and supportive public health information to the general public; and (2) at the community level, this dual-gendered leadership advanced community cohesion toward managing the community-based spread of COVID-19. Future studies may apply a longitudinal, retrospective approach with Canada-wide or cross-national comparison to further evaluate the strengths and weaknesses of dual-gendered leadership.

Affordability, Feasibility, and Accessibility: Companion Animal Guardians with (Dis)Abilities' Access to Veterinary Medical and Behavioral Services during COVID-19.

The research aims to explore COVID-19 health and safety protocol impacts on companion animal guardians living with (dis)abilities relating to veterinary medical and behavioral service access. The COVID-19 global public health crisis has impacted almost all international communities; however, vulnerable and marginalized groups have been disproportionately affected. Within the human-companion animal domain, COVID-19-driven societal impacts (e.g., social, health, and economic) not only boomed with new companion animal guardians, but also negatively influenced guardians' access to veterinary services. Although studies have examined guardian-related COVID-19-specific challenges, there is a paucity of concentration on vulnerable populations, such as persons with disabilities (PWDs). Responding to this research deficit, this study recruited twelve companion animal guardians to participate in semi-structured in-depth interviews, and eight (67%) of the twelve participants self-identified as PWDs. From a PWD perspective, this research reveals three pandemic-triggered primary barriers, preventing PWDs from pursuing veterinary services: (1) service affordability, (2) assistance program feasibility, and (3) veterinary service accessibility. This article argues that PWD-driven approaches could improve existing assistance and support programs to address PWDs' unique requirements, promoting a healthy human-animal bond.

Two-Dimensional Anisotropy Measurements Showing Local Heterogeneity in a Polymer Melt.

In polymers, the rotation of a small solute is nonexponential. Either heterogeneity in the local friction or local anisotropy-a homogeneous process-may be responsible. A new, two-dimensional anisotropy experiment is demonstrated on this problem. In poly(dimethylsiloxane), the rotation of individual solute molecules is found to be exponential, and the observed rate dispersion is primarily due to variation in the local friction. This sample is far from its glass transition. Studies of rate heterogeneity associated with the glass transition must account for the contribution from this polymer-related mechanism.

New molecular probe for the selective detection of zinc ion.

A new multisignaling molecular probe DFDB was designed for the selective detection of Zn(2+). DFDB can be synthesized by a simple one-step reaction in high yield. Theoretical calculation suggests a novel sandwich structure of the DFDB·Zn(2+) complex.

Multiple population-period transient spectroscopy (MUPPETS) of CdSe/ZnS nanoparticles. I. Exciton and biexciton dynamics.

The nonradiative relaxation of both the exciton and biexciton in CdSe/ZnS core-shell nanoparticles have complicated, nonexponential kinetics. This paper presents data on this system from multiple population-period transient spectroscopy (MUPPETS), a method for two-dimensional kinetics. An initial report of a dispersed (nonexponential) biexciton decay [J. Am. Chem. Soc. 2013, 135, 1002] is confirmed in a more rigorous analysis. Additional transient-grating data allow a quantitative treatment of the full, complex MUPPETS data set. The MUPPETS signal has a strong fluence dependence. With extrapolation to the low fluence limit, the ratio of cross sections for ground-to-exciton and exciton-to-biexciton absorption is found to be close to the predictions of the uncorrelated-electron model. The full two-dimensional MUPPETS data set is reported for the first time and is analyzed to detect heterogeneity in the exciton decay. The exciton has a substantial (>40%) nonradiative decay, but it is not due to a subset of defective particles. A surface relaxation in response to formation of the exciton is suggested. This data set is the first capable of detecting correlations between the biexciton and exciton decay mechanism. None is found.

Multiple population-period transient spectroscopy (MUPPETS) of CdSe/ZnS nanoparticles. II. Effects of high fluence and solvent heating.

Multiple population-period transient spectroscopy (MUPPETS) is a six-pulse experiment with two time dimensions that is capable of adding information about systems with complicated kinetics. The core theory for MUPPETS focuses on the χ(5) response of the chromophores. This theory was used to analyze the dynamics of excitons and biexcitons in CdSe/ZnS core-shell nanoparticles in part I of this paper [J. Phys. Chem. B 2013, DOI:10.1021/jp405785a]. In real experiments, the potential role of additional processes must also be considered, in particular, the χ(7), "saturation" of the MUPPETS signal and nonresonant signals from heating of the solvent. A pathway method for calculating fluence effects in MUPPETS is developed. The fluence dependence of the biexciton signal and its sign reversal, as found in part I, are explained without invoking higher excitons or unexpected species. A method is presented for quantitatively predicting the magnitude of signals from solvent heating using an external standard. Thermal effects in this system are found to be too small to affect the conclusions in part I. Their small size, combined with small, systematic errors in the data, also makes it difficult to measure the yield of solvent heat in these experiments.

Multiple population-period transient spectroscopy (MUPPETS) in excitonic systems.

Time-resolved experiments with more than one period of incoherent time evolution are becoming increasingly accessible. When applied to a two-level system, these experiments separate homogeneous and heterogeneous contributions to kinetic dispersion, i.e., to nonexponential relaxation. Here, the theory of two-dimensional (2D) multiple population-period transient spectroscopy (MUPPETS) is extended to multilevel, excitonic systems. A nonorthogonal basis set is introduced to simplify pathway calculations in multilevel systems. Because the exciton and biexciton signals have different signs, 2D MUPPETS cleanly separates the exciton and biexciton decays. In addition to separating homogeneous and heterogeneous dispersion of the exciton, correlations between the exciton and biexciton decays are measurable. Such correlations indicate shared features in the two relaxation mechanisms. Examples are calculated as both 2D time decays and as 2D rate spectra. The effect of solvent heating (i.e., thermal gratings) is also calculated in multidimensional experiments on multilevel systems.

Rate dispersion in the biexciton decay of CdSe/ZnS nanoparticles from multiple population-period transient spectroscopy.

Measurements of biexciton decays in semiconductor nanoparticles are easily contaminated by contributions from photoproducts or higher excitons. Theoretical work has shown that multiple population-period transient spectroscopy (MUPPETS) can measure biexciton decays free from these interferences. In this communication, the biexciton decay of CdSe/ZnS core-shell nanoparticles is measured with MUPPETS. The decay is strongly dispersed (nonexponential) with a more than 5-fold range of rates. This large dispersion must be accounted for in the decay mechanism and in the measurement of biexciton dynamics by more conventional methods. The success of MUPPETS in this context lays the foundation for using it to study exciton-exciton interactions in a variety of materials.