Search

Web3.0, as the link between the physical and digital domains, faces increasing security threats due to its inherent complexity and openness. Traditional intrusion detection systems (IDSs) encounter formidable challenges in grappling with the multidimensional and nonlinear traffic data characteristic of the Web3.0 environment. Such challenges include insufficient samples of attack data, inadequate feature extraction, and resultant inaccuracies in model classification. Moreover, the scarcity of certain traffic data available for analysis by IDSs impedes the system's capacity to document instances of malicious behavior. In response to these exigencies, this paper presents a novel approach to Web3.0 intrusion detection, predicated on the utilization of cycle-consistent generative adversarial networks (CycleGANs). Leveraging the data transformation capabilities of its generator, this method facilitates bidirectional conversion between normal Web3.0 behavioral data and potentially intrusive behavioral data. This transformative process not only augments the diversity and volume of recorded intrusive behaviors but also clandestinely simulates various attack scenarios. Furthermore, through fostering mutual competition and learning between the discriminator and generator, the approach enhances the ability to discern the defining characteristics of potential intrusive behaviors, thereby bolstering the accuracy of intrusion detection. To substantiate the efficacy of the CycleGAN-based intrusion detection method, simulation experiments were conducted utilizing public datasets, including KDD CUP 1999 (KDD), CIC-DDOS2019, CIC-IDS2018, and SR-BH 2020. The experimental findings evince the method's remarkable accuracies across the four datasets, attaining rates of 99.81%, 97.79%, 89.25%, and 95.15%, respectively, while concurrently maintaining low false-positive rates. This research contributes novel insights and methodologies toward the advancement of Web3.0 intrusion detection through the application of CycleGAN technology, which is poised to play a pivotal role in fortifying the security landscape of Web3.0. [ABSTRACT FROM AUTHOR]

Building community resilience has been widely recognized as a learning process at multiple societal levels, yet few prior studies have examined the feedback loop between community‐ and policy‐level learning. Following a qualitative research approach, we document experiential and transformative forms of learning from coastal cyclones in Bangladesh that help local community and their institutions mitigating the impact of cyclonic shocks and recovering from disaster‐related losses, both in the shorter and longer term. This study discovers that such community‐level learning (when scaled‐up) as well as learning from policy failure significantly enhanced programmatic interventions, which in turn enhanced community resilience to cyclones and future disasters. However, this feedback loop can be attenuated by multiple factors, such as lack of attention to community‐level learning by policy/decision makers in non‐disaster settings and the presence of a strong vested interest group, may impede learning‐based policy instrumentation. Boundary spanners or organizations can significantly improve the feedback loop, thus enhancing community resilience and improving policy. [ABSTRACT FROM AUTHOR]

College students are a unique population occupying a distinct life-course and transition period between adolescence and adulthood. Although not monolithic in experiences, knowledge, and demographics, this diverse population is particularly susceptible to immediate, short-term, mid-term, and long-term disaster impacts. Recently, disaster research focusing on college students has rightly focused on the ongoing COVID-19 pandemic. Although the pandemic was a public health disaster interrupting social, developmental, and educational processes for students on a global scale, the climate crisis and related environmental disasters continuously threaten college students' individual development, health, and well-being. Thus, it is critical to understand current knowledge focusing on environmental disasters and college students in order to determine future research needs. This article used the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) approach to examine research on college students and disasters over the past ten years (2014–2023). We identified 67 articles, which we analyzed through a mixed methods approach, including descriptive statistics and thematic analysis. Results indicate that disaster impacts on college students are an understudied topic in the social sciences, especially in an era of more-frequent and -intense environmental hazards. Our findings demonstrate a need to engage college students in disaster research worldwide so that trade schools, colleges, and universities can collaborate with policymakers to build this unique and disproportionately impacted population's capacity to mitigate against, respond to, and recover from environmental hazards in an ever-changing climate. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The upward tendency of global disasters and associated losses urgently calls for enhancing disaster education (DE) and professional training. Although postsecondary education institutions (PSEIs) play an essential role in this educational mission, a comprehensive understanding of DE development in PSEIs remains unclear. In response to this knowledge deficit, this article employed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) approach to explore the current development of DE in PSEIs through reviewing 76 publications from 2011 to 2022 through a mixed-method analysis process (univariate analysis and thematic inquiry). The quantitative analysis outcomes illustrate that the studies were unevenly distributed globally. The qualitative findings demonstrate the following fourfold characteristics of DE in PSEIs: (1) in terms of pedagogical characteristics of DE, there is a call for a radical shift in pedagogical strategies because the conventional teaching approaches are inadequate in tackling the potential risks and emerging hazards; (2) disciplinary and interdisciplinary perspectives have been integrated into DE, addressing diverse disasters and their differential influences; (3) through community-based partnerships, PSEIs can provide informal and nonformal education to affected individuals and communities; and (4) interconnections between DE and other educational approaches that broadly address global climate change have been recognized, contributing to resilience and sustainability. Based on these outcomes, this study recommends future DE-specific research could focus on (1) exploring potential radical pedagogical approaches to respond to emerging risks and hazards, (2) stimulating cross-disciplinary collaboration to address the full spectrum of disasters' societal impacts, and (3) increasing collaboration between PSEIs and nonacademic organizations to raise grassroots awareness through informal DE. The increasing number of disasters worldwide encourages the development of DE, especially at PSEIs. A nuanced understanding of the DE development in PSEIs will identify the strengths and areas for improvement, better preparing future researchers, educators, practitioners, and policymakers. Having focused on DE at PSEIs, this literature review examined 76 journal articles published from 2011 to 2022. Disasters are a global issue, and the literature review outcomes show the uneven distribution of DE on a global scale. Although interdisciplinary approaches have been applied to DE in PSEIs to examine disaster's diverse impacts, innovative pedagogies are needed to address the emerging issues associated with extreme events. DE provides community outreach activities to educate and support the individuals and communities hit by disasters. DE also joins other educational missions to contribute to the global issues of climate change, resilience, and sustainability. These findings suggest that future improvement could focus on developing novel pedagogies, enhancing cross-disciplinary collaboration, and promoting community outreach and public education. [ABSTRACT FROM AUTHOR]

The fast unfolding of the global COVID-19 pandemic has disproportionately affected the homeless sector by triggering tremendous challenges for individuals experiencing homelessness (IEHs) and related service agencies. This quick-response research project qualitatively collected time-sensitive data from the IEHs and service stakeholders (SSs) experiences, challenges, efforts, and suggestions during the first wave of COVID-19 in the two most populated municipalities in the province of Nova Scotia, Canada, namely, Halifax Regional Municipality and Cape Breton Regional Municipality. Through analyzing and synthesizing the standpoints from both IEHs and SSs, this technical note presents recommendations, addressing the practical challenges that IEHs have been confronting during COVID-19 and systemic issues in which homelessness is rooted. These recommendations will assist community-based agencies in improving their emergency response capacity, better serving IEHs in COVID-19 in particular, and supporting other vulnerable and marginalized populations in future extreme events in general. COVID-19 has created major challenges for people experiencing homelessness as well as for service organisations working to help. This research project interviewed people experiencing homelessness as well as service providers in the Halifax and Cape Breton Regional Municipalities of Nova Scotia, Canada. They were asked about their experiences during COVID-19, as well as challenges encountered, how they responded, and suggestions for changes needed. This article presents recommendations for changes needed to address both the challenges that people experiencing homelessness faced during COVID-19, as well as other problems of homelessness that have existed for years. These recommendations will assist service organizations to improve the ways they respond to emergencies in order to better serve people experiencing homelessness–not only during COVID-19 but also during other challenging events in the future. The recommendations include: all services working with people experiencing homeless need to work together and advocate for shelter/affordable housing, need to include the voices of people experiencing homelessness in decision-making processes, federal government needs to work with provinces when providing emergency funding supports, and need to ensure that essential information is fully accessible to all vulnerable and marginalized communities. [ABSTRACT FROM AUTHOR]

Green social work (GSW) is a nascent framework within the social work field that provides insights regarding social workers' engagement in disaster settings. Although this framework has recently garnered more attention, it remains under-researched and underdeveloped within the context of social work research, education, and practice in Canada and internationally. To further develop GSW in social work education and professional training, we considered how social work students and practitioners can use a learning framework to understand the impact and build their capacities to serve vulnerable and marginalized populations in diverse disaster settings. To do this, we developed a four-step case study approach, as follows: (1) provide detailed background information on the cases, (2) describe how each case is relevant to social work, (3) discuss how each case informs social work practice from a GSW perspective, and (4) provide recommendations for social work practitioners and students using GSW in future disaster-specific efforts. This case study approach centers on natural, technological, and intentional/willful hazards that examine current GSW research–practice engagement in Canada and internationally. Applying this four-step case study approach to three extreme events in Canada and internationally (a natural hazard, a technological hazard, and an intentional/willful hazard) illustrates it as a potential method for social work students and professionals to build their GSW capacities. This will assist in building the resilience of Canadian and international communities—especially those who have been historically marginalized. This article sheds light on how current social work education and professional training should develop new approaches to incorporate the GSW framework into the social work curriculum at large in order to prepare for future extreme events while incorporating environmental and social justice into research and practice. [ABSTRACT FROM AUTHOR]

Cultural responsivity in academic research is central to the use of language that is representative and inclusive of Indigenous worldviews on gender and sexuality diversity. This article uses the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) approach to explore current studies' contribution to the use of gender and sexuality diverse terminology and language that is representative of Indigenous worldviews. A systematic review of 85 journal articles (published between January 2000 and June 2021) generates both quantitative results regarding the frequency of terms used and qualitative outcomes of actively used terminologies, geographic regions, identified populations, and gender and sexuality diversity-specific themes in Indigenous studies. A substantial glossary of terminology characteristic of the multiplicity of gender and sexuality diversity was identified, however, further research examining gender and sexuality diversity from the perspective of Indigenous worldviews is needed to align with the best practices of equity, diversity, inclusion and belonging. [ABSTRACT FROM AUTHOR]

As a specific data hiding technique, reversible data hiding (RDH) has recently received extensive attention. By this technique, both the embedded data and the original cover image can be exactly extracted from the marked image. In our previous work, a general expansion-shifting model for RDH is proposed by introducing the so-called reversible embedding function (REF). With REF, RDH can be designed and the corresponding rate-distortion formulations can be established, providing an approach to optimize the reversible embedding performance. In this paper, by extending our previous work, optimal REF for one-dimensional histogram is investigated, and all optimal REF are derived in this case when the maximum modification to the cover pixel is limited as a small value. Moreover, based on the derived optimal REF for one-dimensional histogram and multiple histograms modification, a practical RDH scheme is presented and it is experimental verified better than some state-of-the-art algorithms in terms of capacity-distortion performance. [ABSTRACT FROM AUTHOR]

Social work's response to global climate change has dramatically increased over the last several years. Similarly, growing attention has been paid to rural social work; less clear, however, is how social work, responsive to global climate change, is developed, deployed, and understood in rural contexts; this systematic review elaborates on current social work contributions (research, practice, and policymaking), promoting environmental justice and sustainability in rural communities. Utilizing the preferred reporting items for systematic reviews and meta-analyses (PRISMA) approach, this article thematically analyzed and synthesized 174 journal articles on social work-specific interventions and environmental justice. The results illustrate insights into the experiences, practices, or objectives of rural social workers vis-à-vis climate change. Significant themes from the literature demonstrated that gender, age, and race limited access to social work services and climate-related disaster response support in rural settings; this article argues that rural community-driven social work practices focused on environmental justice and sustainability should be encouraged and that policy advocacy attentive to climate change and its impact on vulnerable and marginalized groups should be pursued. Current and prospective social work scholars, practitioners, policymakers, and other stakeholders should collaborate with local rural communities to address their unique needs related to climate change. In turn, grassroots strategies should be co-developed to promote climate change adaptation and disaster risk reduction, ultimately achieving the goal of building resilient, healthy, and sustainable rural communities. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Although the need for cultural competence among healthcare service providers and other practitioners has long been recognized, there has been much less focus on this concept in the field of hazards and disaster research. To help fill this gap, this technical note offers a definitional framework for building cultural competence among hazards and disaster researchers and describes a training module that assists with developing such competency. Drawing on the extant literature, this article conceptualizes cultural competence in hazards and disaster research as an ongoing process that contributes to an understanding of the cultural attributes of affected individuals, households, communities, and societies that researchers are attempting to characterize. The four-step process presented here helps researchers move from cultural awareness to cultural knowledge to cultural sensitivity, and ultimately, to cultural competence. This ongoing practice requires reflexivity, respect, and humility. The time and effort involved in developing cultural competence can promote ethical research, improve the research experience for participants, enrich the quality of the data collected, and enhance the overall quality of knowledge creation and mobilization. [ABSTRACT FROM AUTHOR]

This article aims to develop community-contextualised pedagogical innovations to embed disaster components into core social work curriculum through a research methods course. Professional social work education continues to lack a community-contextualised curriculum and professional training that reflects the complexities of extreme events associated with community and human service. This absence jeopardises the advancement of social work engagement in better providing humanitarian support for individuals, families and communities affected by extreme events. Through an undergraduate social work research methods course, this case study qualitatively analysed the instructor's teaching experience, self-reflection and in-class observation. The study presents three major community-contextualised pedagogical innovations of integrating disaster components into the research methods course: public media critique, amidst-disaster community-based participation and observation and practice situation discussion. These pedagogical efforts support the students' exploration and development of various research paradigms and strengthen their ability to connect research with practice, thus addressing the community-driven, short-term necessities and long-term development requirements. This contextualising process, which forms a community-based living laboratory, inspires instructors to integrate community-driven characteristics into their pedagogical instruments. The process illustrates a potential pedagogical framework for research methods courses, in particular, and for social work curriculum, in general. [ABSTRACT FROM AUTHOR]

During the COVID-19 emergency response of 'staying the blazes home' in Nova Scotia, Canada, frontline social workers worked tirelessly 'out of the home' to secure safe dwellings for those on the street, living in shelters, and/or precariously housed. When the province moves to the reopening and recovery stage, social work strategies will focus on reducing homeless people's vulnerabilities, aiming to offer safe and dignified living. [ABSTRACT FROM AUTHOR]

Methods matter. They influence what we know and who we come to know about in the context of hazards and disasters. Research methods are of profound importance to the scholarly advancement of the field and, accordingly, a growing number of publications focus on research methods and ethical practices associated with the study of extreme events. Still, notable gaps exist. The National Science Foundation-funded Social Science Extreme Events Research (SSEER) network was formed, in part, to respond to the need for more specific information about the status and expertise of the social science hazards and disaster research workforce. Drawing on data from 1,013 SSEER members located across five United Nations (UN) regions, this article reports on the demographic characteristics of SSEER researchers; provides a novel inventory of methods used by social science hazards and disaster researchers; and explores how methodological approaches vary by specific researcher attributes including discipline, professional status, researcher type based on level of involvement in the field, hazard/disaster type studied, and disaster phase studied. The results have implications for training, mentoring, and workforce development initiatives geared toward ensuring that a diverse next generation of social science researchers is prepared to study the root causes and social consequences of disasters. [ABSTRACT FROM AUTHOR]

There is a need to better understand long-term disaster recovery and reconstruction challenges in diverse communities. This case study was part of a larger study undertaken by the Rebuilding Lives Post-Disaster research partnership, where field research was conducted in disaster-affected communities in Canada, the USA, Australia, India, Pakistan, and Taiwan. The objective of this exploratory case study was to focus on experiences of affected migrant workers from diverse communities in Florida, USA, in relation to long-term disaster recovery and reconstruction work following hurricanes, to ensure that lessons learned from these experiences could inform best practices and policy. The study focused particularly on the role of community processes and dynamics in shaping postdisaster recovery. Qualitative research explored diverse experiences of participants through interviews with government officials, community leaders, and disaster responders. The study found that migrant workers faced challenges due to the lack of consideration with regard to immigration status, linguistic, and cultural needs in disaster recovery. IMPLICATIONS Disaster recovery processes need to consider the diversity of affected populations to ensure assistance and responses meet the differing needs of all community members in postdisaster recovery. All members of diverse communities should be included in disaster response and longer-term recovery efforts. Social workers can assist in ensuring that diversity is a consideration in disaster and emergency management. [ABSTRACT FROM AUTHOR]

It is increasingly recognized that social work has a vital role to play in shaping effective responses to environmental degradation, climate change and disasters. Innovative teaching and learning strategies can be used to facilitate understanding of complex, interrelated and systemic social, economic and environmental challenges. This article shares the development and design of a new social work course entitled ‘Social work and sustainable social development’. Teaching methods and strategies are provided including individual and group mind maps, case studies and presentations, guest speakers and evaluation methods. Implications for social work education and the profession are discussed in order to build capacity to address environmental justice and sustainability. [ABSTRACT FROM PUBLISHER]

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. [ABSTRACT FROM AUTHOR]

Simple Summary: Compounding pre-existing diverse vulnerabilities, pet owners living with (dis)abilities are expected to confront more challenges than their peers without (dis)abilities. However, there is a paucity of literature investigating COVID-19-specific impacts on access to veterinary medical and behavioral services from the lens of persons with (dis)abilities (PWDs). Through semi-structured in-depth interviews, this study highlights PWDs' difficulties, three-fold: (1) COVID-19 has worsened PWDs' already precarious financial capacity to pay for veterinary services, (2) existing assistance and support programs do not effectively address PWDs' unique requirements to support their companion animals' health needs, and (3) public health protocols triggered public transportation challenges for PWDs who must now also adapt to complicated curbside services. Building PWD-driven social assistance and support programs would help reduce these challenges and promote health and well-being for both PWDs and their companion animals. 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. [ABSTRACT FROM AUTHOR]

This study contributes to an in-depth examination of how Wenchuan earthquake disaster survivors utilize intensive built environment reconstruction outcomes (housing and infrastructural systems) to facilitate their long-term social and economic recovery and sustainable rural development. Post-disaster recovery administered via top-down disaster management systems usually consists of two phases: a short-term, government-led reconstruction (STGLR) of the built environment and a long-term, survivor-led recovery (LTSLR) of human and social settings. However, current studies have been inadequate in examining how rural disaster survivors have adapted to their new government-provided housing or how communities conducted their long-term recovery efforts. This qualitative case study invited sixty rural disaster survivors to examine their place-making activities utilizing government-delivered, urban-style residential communities to support their long-term recovery. This study discovered that rural residents' recovery activities successfully perpetuated their original rural lives and rebuilt social connections and networks both individually and collectively. However, they were only able to manage their agriculture-based livelihood recovery temporarily. This research suggests that engaging rural inhabitants' place-making expertise and providing opportunities to improve their housing and communities would advance the long-term grassroots recovery of lives and livelihoods, achieving sustainable development. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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., (© 2024 Wiley‐VCH GmbH.)

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., Competing Interests: AM and CM are the employees of Vancouver Humane Society. Neither of them received financial support to conduct this research. The remaining author declares that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Morris, Wu and Morales.)

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.

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) 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.

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.