The popularity of the term polycrisis suggests a growing demand for new thinking about the world's intersecting crises, but loose and haphazard uses of the concept impede knowledge generation. The special issue, ‘Polycrisis in the Anthropocene’, aims to close the gap. This introductory comment first elaborates upon three key contributions of the lead article ‘Global Polycrisis: The Causal mechanisms of Crisis Entanglement’: a conceptualization of crisis as systemic disequilibrium; the distinction between the slow-moving stresses and the fast-moving trigger events that interact to generate a crisis; and a grammar with which to map the causality of crisis interactions. The commentary then explores three key debates around the polycrisis concept: Are we in a polycrisis, at risk of a polycrisis, or neither? Is the present polycrisis truly unique and unprecedented? And where are power and agency in a systemic approach to polycrisis? These ongoing debates suggest promising directions for polycrisis research that could feature in this special issue and advance the field of polycrisis analysis.

This commentary introduces the special issue ‘Polycrisis in the Anthropocene’ by elaborating upon three major contributions of its lead article, ‘Global Polycrisis: The Causal Mechanisms of Crisis Entanglement’, and exploring three key debates surrounding the polycrisis concept. It invites others to contribute to the special issue in order to advance polycrisis analysis, build a community of knowledge and practice, and generate new insights and strategies with which to address the world's worsening crises.

The popularity of the term polycrisis suggests a growing demand for new thinking about the world's intersecting crises, but loose and haphazard uses of the concept impede knowledge generation. The special issue, ‘Polycrisis in the Anthropocene’, aims to close the gap. This introductory comment first elaborates upon three key contributions of the lead article ‘Global Polycrisis: The Causal mechanisms of Crisis Entanglement’: a conceptualization of crisis as systemic disequilibrium; the distinction between the slow-moving stresses and the fast-moving trigger events that interact to generate a crisis; and a grammar with which to map the causality of crisis interactions. The commentary then explores three key debates around the polycrisis concept: Are we in a polycrisis, at risk of a polycrisis, or neither? Is the present polycrisis truly unique and unprecedented? And where are power and agency in a systemic approach to polycrisis? These ongoing debates suggest promising directions for polycrisis research that could feature in this special issue and advance the field of polycrisis analysis.

Inviting contributions and debates to Global Sustainability journal's special issue ‘Polycrisis in the Anthropocene’.

Multiple global crises – including the pandemic, climate change, and Russia's war on Ukraine – have recently linked together in ways that are significant in scope, devastating in effect, but poorly understood. A growing number of scholars and policymakers characterize the situation as a ‘polycrisis’. Yet this neologism remains poorly defined. We provide the concept with a substantive definition, highlight its value-added in comparison to related concepts, and develop a theoretical framework to explain the causal mechanisms currently entangling many of the world's crises. In this framework, a global crisis arises when one or more fast-moving trigger events combine with slow-moving stresses to push a global system out of its established equilibrium and into a volatile and harmful state of disequilibrium. We then identify three causal pathways – common stresses, domino effects, and inter-systemic feedbacks – that can connect multiple global systems to produce synchronized crises. Drawing on current examples, we show that the polycrisis concept is a valuable tool for understanding ongoing crises, generating actionable insights, and opening avenues for future research.

The term ‘polycrisis’ appears with growing frequently to capture the interconnections between global crises, but the word lacks substantive content. In this article, we convert it from an empty buzzword into a conceptual framework and research program that enables us to better understand the causal linkages between contemporary crises. We draw upon the intersection of climate change, the covid-19 pandemic, and Russia's war in Ukraine to illustrate these causal interconnections and explore key features of the world's present polycrisis.

Multiple global crises – including the pandemic, climate change, and Russia's war on Ukraine – have recently linked together in ways that are significant in scope, devastating in effect, but poorly understood. A growing number of scholars and policymakers characterize the situation as a ‘polycrisis’. Yet this neologism remains poorly defined. We provide the concept with a substantive definition, highlight its value-added in comparison to related concepts, and develop a theoretical framework to explain the causal mechanisms currently entangling many of the world's crises. In this framework, a global crisis arises when one or more fast-moving trigger events combines with slow-moving stresses to push a global system out of its established equilibrium and into a volatile and harmful state of disequilibrium. We then identify three causal pathways – common stresses, domino effects, and inter-systemic feedbacks – that can connect multiple global systems to produce synchronized crises. Drawing on current examples, we show that the polycrisis concept is a valuable tool for understanding ongoing crises, generating actionable insights, and opening avenues for future research.

No longer a mere buzzword, the ‘polycrisis’ concept highlights causal interactions among crises to help navigate a tumultuous future.

To examine whether suboptimal performance as determined by formal validity testing would predict neurocognitive scores in a sample of 83 pre-surgical, non-litigating epilepsy patients.

Participants were 83 patients who underwent comprehensive outpatient neuropsychological testing as part as their evaluation as epilepsy surgery candidates. The sample consisted of 41 females and 42 males, with 72 patients identifying as White, 5 as Black, 2 as Hispanic, 1 as Asian, and 2 as other. Mean age was 36 (SD=12.4) mean FSIQ was 87 (SD=12.7), mean years of education of 12.9 (SD=2.1). Each patient’s assessment included a stand-alone performance validity test (PVTs)— Word Memory Test (WMT), the Test of Memory Malingering (TOMM), or the Medical Symptom Validity Test (MSVT)—as well as two embedded measures of validity—the California Verbal Learning Test Forced Choice (CVLT FC) and WAIS-IV Reliable Digit Span (RDS). Pass/fail rates were analyzed, with valid performance being defined as pass score on at least two of the completed PVTs (N=73 Pass Effort group 86.9%; N=10 Failed Effort group 11.9%). Point-biserial Pearson correlations were conducted to determine the relationship between validity pass/fail status and WAIS-IV FSIQ, VCI, and PRI scores, CVLT-II Trials 1-5 Total T scores, CVLT-II Long Delay Free Recall z scores, WMS-III Logical Memory II T scores, BVMT Total Recall T scores, BVMT Delayed Recall T scores, and Trail Making Test (TMT) B T scores.

Significant relationships were found between Failed Effort group and all neurocognitive scores except BVMT Total Recall. On average, the Failed Effort group obtained significantly lower FSIQ (M=76.57, SD=10.94), VCI (M=80.89, SD=16.03), PRI (M=81.00, SD=14.91), CVLT-II Trials 1-5 Total (M =34, SD=6.89), CVLT-II Long Delay Free Recall (M =-2.44, SD=1.43), WMS-IV Logical Memory II (M =4.83, SD=2.79), BVMT Delayed Recall (M=26.38, SD=6.41), and TMT B (M=29.70, SD=11.46) standard scores compared to the Pass Effort group (FSIQ M=88.09, SD=12.52; VCI M=92.13, SD=13.61; PRI M=91.14, SD=12.06; CVLT-II Trials 1-5 Total M=47.86, SD=12.02; CVLT- II Long Delay Free Recall M=-.44, SD=1.11; WMS-III Logical Memory II M=8.41, SD=3.17; BVMT Delayed Recall M=39.19, SD=12.66; TMT B M=39.34, SD=13.18). Correlation coefficients were r=-.266* (FSIQ), r=-.255* (VCI), r=-.271* (PRI), r=.361**(CVLT-II Total), r=-.474** (CVLT-II LDFR), r=-.298** (WMS-IV LM II), r=-.308** (BVMT DR), and r=-.240* (TMTB). All coefficients were significant at the .05 (*) or .01 (**) level.

Results suggest that pass/fail status on formal validity testing predicts depressed performance on a variety of neurocognitive measures. Therefore, predicting surgical outcome of resection/ablation (e.g., compensation of contralateral hemisphere) should not be based upon neuropsychological memory performance alone when there are failures on tests of engagement as memory scores have strong correlations to pass/fail status on formal validity testing. Overall, this emphasizes the importance of routinely integrating PVTs as part of pre-epilepsy surgery neuropsychological evaluations.

Significant advances in the research of sport-related concussion (SRC) and repetitive head impacts (RHI) over the previous decade have translated to improved injury identification, diagnosis, and management. However, an objective gold standard for SRC/RHI treatment has remained elusive. SRC often result in heterogenous clinical outcomes, and the accumulation of RHI over time is associated with long-term declines in neurocognitive functioning. Medical management typically entails an amalgamation of outpatient medical treatment and psychiatric and/or behavioral interventions for specific symptoms rather than treatment of the underlying functional and/or structural brain injury. Transcranial photobiomodulation (tPBM), a form of light therapy, has been proposed as a non-invasive treatment for individuals with traumatic brain injuries (TBI), possibly including SRC/RHI. With the present proof-of-concept pilot study, we sought to address important gaps in the neurorehabilitation of former athletes with a history of SRC and RHI by examining the effects of tPBM on neurocognitive functioning.

The current study included 49 participants (45 male) with a history of SRC and/or RHI. Study inclusion criteria included: age 18-65 years and a self-reported history of SRC and/or RHI. Exclusion criteria included: a history of neurologic disease a history of psychiatric disorder, and MRI contraindication. We utilized a non-randomized proof-of-concept design of active treatment over the course of 8-10 weeks, and neurocognitive functioning was assessed at pre- and post-treatment. A Vielight Neuro Gamma at-home brain tPBM device was distributed to each participant following baseline assessment.

Participants completed standardized measures of neurocognitive functioning, including the California Verbal Learning Test (CVLT-3), Delis Kaplan Executive Function System (D-KEFS), Continuous Performance Test (CPT-3), and The NIH Toolbox Cognition Battery. Neurocognitive assessments were collected prior to and following tPBM treatment. Paired t-tests and Wilcoxon’s signed-rank tests were used to evaluate change in performance on measures of neurocognitive functioning for normal and nonnormal variables, respectively, and estimates of effect size were obtained.

Study participants’ ability for adapting to novel stimuli and task requirements (i.e., fluid cognition; t=5.96; p<.001; d=.90), verbal learning/encoding (t=3.20; p=.003; d=.48) and delayed recall (z=3.32; p=.002; d=.50), processing speed (t=3.13; p=.003; d=.47), sustained attention (t=-4.39; p<.001; d=-.71), working memory (t=3.61; p=.001; d=.54), and aspects of executive functioning improved significantly following tPBM treatment. No significant improvements in phonemic and semantic verbal fluencies, reading ability, and vocabulary were shown following tPBM treatment.

The results of this pilot study demonstrate that following 8-10 weeks of active tPBM treatment, retired athletes with a history of SRC and/or RHI experienced significant improvements in fluid cognition, learning and memory, processing speed, attention, working memory, and aspects of executive functioning. Importantly, the majority of effect sizes ranged from moderate to large, suggesting that tPBM has clinically meaningful improvements on neurocognitive functioning across various cognitive domains. These results offer support for future research employing more rigorous study designs on the potential neurorehabilitative effects of tPBM in athletes with SRC/RHI.

Physician-scientist training programs expect applicants to have had extensive research experience prior to applying. Even at the best of times, this leaves individuals from underserved and underrepresented backgrounds at a competitive disadvantage, especially those remote from major academic centers. The COVID-19 pandemic exacerbated that disadvantage by closing research laboratories and suspending summer research opportunities.

The Virtual Summer Research Program (VSRP) was designed to combat this shortfall by helping participating students become better informed and better prepared for applying to MD/DO–PhD programs. 156 participants were recruited from historically black colleges and universities and from national organizations for underrepresented trainees. Participants were paired with medical school faculty members and current MD/DO–PhD students from 35 participating institutions. The program lasted for at least 4 weeks and included a short research project, interactive sessions, journal clubs, social events, and attendance at a regional American Physician Scientists Association conference.

In follow-up surveys, participants reported improvements in their science-related skills and in their confidence in becoming a physician-scientist, applying to training programs, and navigating mentorship relationships. A follow-up study completed one year later indicated that participants felt they had benefited from an enhanced skill set, long-term relationships with their mentors, and connections to the physician-scientist community at large.

The results suggest that VSRP met its primary goals, which were to provide a diverse group of trainees with mentors, provide skills and resources for MD/DO–PhD application and matriculation and to support the development of longitudinal relationships between VSRP mentees and APSA. VSRP provides an approach that can be applied at an even larger scale when the constraints caused by a global pandemic have lifted.

A standardised multi-site approach to manage paediatric post-operative chylothorax does not exist and leads to unnecessary practice variation. The Chylothorax Work Group utilised the Pediatric Critical Care Consortium infrastructure to address this gap.

Over 60 multi-disciplinary providers representing 22 centres convened virtually as a quality initiative to develop an algorithm to manage paediatric post-operative chylothorax. Agreement was objectively quantified for each recommendation in the algorithm by utilising an anonymous survey. “Consensus” was defined as ≥ 80% of responses as “agree” or “strongly agree” to a recommendation. In order to determine if the algorithm recommendations would be correctly interpreted in the clinical environment, we developed ex vivo simulations and surveyed patients who developed the algorithm and patients who did not.

The algorithm is intended for all children (<18 years of age) within 30 days of cardiac surgery. It contains rationale for 11 central chylothorax management recommendations; diagnostic criteria and evaluation, trial of fat-modified diet, stratification by volume of daily output, timing of first-line medical therapy for “low” and “high” volume patients, and timing and duration of fat-modified diet. All recommendations achieved “consensus” (agreement >80%) by the workgroup (range 81–100%). Ex vivo simulations demonstrated good understanding by developers (range 94–100%) and non-developers (73%–100%).

The quality improvement effort represents the first multi-site algorithm for the management of paediatric post-operative chylothorax. The algorithm includes transparent and objective measures of agreement and understanding. Agreement to the algorithm recommendations was >80%, and overall understanding was 94%.

Social cognition has not previously been assessed in treatment-naive patients with chronic schizophrenia, in patients over 60 years of age, or in patients with less than 5 years of schooling.

We revised a commonly used measure of social cognition, the Reading the Mind in the Eyes Test (RMET), by expanding the instructions, using both self-completion and interviewer-completion versions (for illiterate respondents), and classifying each test administration as ‘successfully completed’ or ‘incomplete’. The revised instrument (RMET-CV-R) was administered to 233 treatment-naive patients with chronic schizophrenia (UT), 154 treated controls with chronic schizophrenia (TC), and 259 healthy controls (HC) from rural communities in China.

In bivariate and multivariate analyses, successful completion rates and RMET-CV-R scores (percent correct judgments about emotion exhibited in 70 presented slides) were highest in HC, intermediate in TC, and lowest in UT (adjusted completion rates, 97.0, 72.4, and 49.9%, respectively; adjusted RMET-CV-R scores, 45.4, 38.5, and 34.6%, respectively; all p < 0.02). Stratified analyses by the method of administration (self-completed v. interviewer-completed) and by education and age (‘educated-younger’ v. ‘undereducated-older’) show the same relationship between groups (i.e. NC>TC>UT), though not all differences remain statistically significant.

We find poorer social cognition in treatment-naive than in treated patients with chronic schizophrenia. The discriminant validity of RMET-CV-R in undereducated, older patients demonstrates the feasibility of administering revised versions of RMET to patients who may otherwise be considered ineligible due to education or age by changing the method of test administration and carefully assessing respondents' ability to complete the task successfully.

Shortages of personal protective equipment during the coronavirus disease 2019 (COVID-19) pandemic have led to the extended use or reuse of single-use respirators and surgical masks by frontline healthcare workers. The evidence base underpinning such practices warrants examination.

To synthesize current guidance and systematic review evidence on extended use, reuse, or reprocessing of single-use surgical masks or filtering face-piece respirators.

We used the World Health Organization, the European Centre for Disease Prevention and Control, the US Centers for Disease Control and Prevention, and Public Health England websites to identify guidance. We used Medline, PubMed, Epistemonikos, Cochrane Database, and preprint servers for systematic reviews.

Two reviewers conducted screening and data extraction. The quality of included systematic reviews was appraised using AMSTAR-2. Findings were narratively synthesized.

In total, 6 guidance documents were identified. Levels of detail and consistency across documents varied. They included 4 high-quality systematic reviews: 3 focused on reprocessing (decontamination) of N95 respirators and 1 focused on reprocessing of surgical masks. Vaporized hydrogen peroxide and ultraviolet germicidal irradiation were highlighted as the most promising reprocessing methods, but evidence on the relative efficacy and safety of different methods was limited. We found no well-established methods for reprocessing respirators at scale.

Evidence on the impact of extended use and reuse of surgical masks and respirators is limited, and gaps and inconsistencies exist in current guidance. Where extended use or reuse is being practiced, healthcare organizations should ensure that policies and systems are in place to ensure these practices are carried out safely and in line with available guidance.