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High coastal nutrient loading can cause changes in seagrass chemistry traits that may lead to variability in seagrass litter decomposition processes. Such changes in decomposition have the potential to alter the carbon (C) sequestration capacity within seagrass meadows ('blue carbon'). However, the external and internal factors that drive the variability in decomposition rates of the different organic matter (OM) types of seagrass are poorly understood, especially recalcitrant OM (i.e. cellulose-associated OM and lignin-associated OM), thereby limiting our ability to evaluate the C sequestration potential. It was conducted a laboratory incubation to compare differences in the decomposition of Halophila beccarii litter collected from seagrass meadows with contrasting nutrient loading histories. The exponential decay constants of seagrass litter mass, cellulose-associated OM and lignin-associated OM were 0.009-0.032, 0.014-0.054 and 0.009-0.033 d-1, respectively. The seagrass litter collected from meadows with high nutrient loading exhibited greater losses of mass (25.0-41.2 %), cellulose-associated OM (2.8-18.5 %) and lignin-associated OM (9.6-31.2 %) than litter from relatively low nutrient loading meadows. The initial and temporal changes of the litter nitrogen (N) and phosphorus (P) concentrations, stoichiometric ratios of lignin/N, C/N, and C/P, and cellulose-associated OM content, were strongly correlated with the losses of litter mass and different types of OM. Further, temporal changes of litter C and OM types, particularly the OM and labile OM concentrations, were identified as the main driving factors for the loss of litter mass and loss of different OM types. These results indicated that nutrient-loaded seagrass litter, characterized by elevated nutrient levels and diminished amounts of recalcitrant OM, exhibits an accelerated decay rate for the recalcitrant OM. These differences in litter quality would lead to a reduced contribution of seagrass litter to long-term C stocks in eutrophic meadows, thereby weakening the stability of C sequestration. Considering the expected changes in seagrass litter chemistry traits and decay rates due to long-term nutrient loading, this study provides useful information for improving C sequestration capabilities through effective pollution management.

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There has been limited research into arsenolipid toxicological risks and health-related outcomes due to challenges with their separation, identification, and quantification within complex biological matrices (e.g., fish, seaweed). Analytical approaches for arsenolipid identification such as suspect screening have not been well documented and there are no certified standard reference materials, leading to issues with reproducibility and uncertainty regarding the accuracy of results. In this study, a detailed workflow for the identification of arsenolipids utilizing suspect screening coupled with data independent analysis is presented and applied to three commercially available standard reference materials (Hijiki seaweed, dogfish liver, and tuna). Hexane and dichloromethane/methanol extraction, followed by reversed-phase high-performance liquid chromatography-inductively coupled plasma mass spectrometry and liquid chromatography-electrospray ionization-quadrupole time-of-flight mass spectrometry. Using the workflow developed, mass fragmentation matching, mass error calculations, and retention time matching were performed to identify suspect arsenolipids. Arseno-fatty acids (AsFAs), arsenohydrocarbons (AsHCs), and arsenosugar phospholipids (AsSugPLs) were identified with high confidence; AsHC332, AsHC360, and AsSugPL720 in seaweed, AsHC332 in tuna, and AsFA474 and AsFA502 in the dogfish liver. AsHC332, AsHC360, and AsFA502 were identified as promising candidates for further work on synthesis, quantification using MS/MS, and toxicity testing.

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PURPOSE: To evaluate the safety, effectiveness, and patient satisfaction of doxycycline sclerotherapy for aneurysmal bone cysts (ABCs) and unicameral bone cysts (UBCs). MATERIALS AND METHODS: This is an institutional review board-approved single center retrospective review of all ABCs and UBCs of the appendicular skeleton and pelvis completing doxycycline sclerotherapy and having at least 2 years of follow-up from 2007 to 2021. Radiographic outcomes in a patient cohort were assessed with a modified Neer score. Patient-reported outcome surveys (PROs) were completed by a subgroup of the cohort assessing pain after treatment (Likert scale), functional outcomes (Patient-Reported Outcomes Measurement Instrumentation System, PROMIS), and overall patient satisfaction (adapted from Musculoskeletal Tumor Society, MSTS). RESULTS: Seventy-seven lesions met inclusion criteria, with 55 (71%) receiving Bone Void Filler (BVF) in addition to doxycycline. Of the 77 lesions, 76 (99%) were successfully treated. Twelve lesions (16%) recurred but resolved with additional doxycycline treatment. One lesion failed sclerotherapy, requiring surgical excision. Of the 383 total treatments performed, 17 resulted in SIR classified adverse events (9 with grade 1, 7 with grade 2, and 1 with grade 3). Twenty-five of the 77 cases (32%) completed PROs with 20 (80%) having little to no pain and 15 (60%) having no functional impairment after completing treatment. The PROs documented high levels of satisfaction, with all patients agreeing that they would undergo doxycycline sclerotherapy again if given the option. CONCLUSION: Doxycycline sclerotherapy is a safe and effective stand-alone treatment for ABCs and UBCs.

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Background and Purpose: The ability to safely care for patients with pulmonary artery catheters (PACs) is an essential skill for critical care nurses, yet no valid and reliable test exists to assess this knowledge. The purpose of this study was to assess the psychometrics of a test created to assess nurses' knowledge of PAC safe-care. Methods: Reliability was assessed using Kuder-Richardson-20, and validity was assessed using item difficulty, discrimination, and known-groups comparison. Results: The sample (N = 95) consisted of new graduates and experienced nurses. Reliability was less than desired (.657) but expected due to the small number of test items. Validity was supported by item difficulty, discrimination indices, and known-groups comparison. Conclusion: Assessing the reliability and validity of test questions is a crucial step for creating accurate instruments to assess safe-care practices, which can be used to improve course content and evaluation methods.

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Inflammatory myofibroblastic tumor (IMT) is a rare soft tissue tumor primarily occurring in the abdominopelvic region of young patients, and it is characterized by spindle-shaped myofibroblasts, or fibroblasts surrounded by inflammatory infiltrate. Herein, we report a case of a 24-year-old male with a firm submucosal mass in the anterior right vocal fold diagnosed as an IMT that recurred 14 months later. The tumor demonstrated a novel THBS1::ALK fusion containing Exons 1-7 of the thrombospondin 1 (THBS1) gene fused to Exon 19 of the anaplastic lymphoma kinase (ALK) gene via next-generation sequencing with the NextSeq sequencer. The fusion of THBS1 to ALK potentially results in increased expression and constitutive activation of the ALK kinase domain. These findings not only broaden the repertoire of known ALK fusion partners implicated in tumorigenesis but also provide a novel avenue for investigating the etiology of recurrent IMT by considering this fusion event as a causal factor. To our knowledge, this is the second case of IMT of the larynx with this novel mutation reported in the literature and the first such case with a detailed description of this specific fusion and clinical recurrence.

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Blue carbon ecosystems (BCEs), such as mangroves, saltmarshes, and seagrasses, are important nature-based solutions for climate change mitigation and adaptation but are threatened by degradation. Effective BCE restoration requires strategic planning and site selection to optimise outcomes. We developed a Geographic Information System (GIS)-based multi-criteria decision support tool to identify suitable areas for BCE restoration along the 2512 km-long coastline of Victoria, Australia. High-resolution spatial data on BCE distribution, coastal geomorphology, hydrodynamics, and land tenure were integrated into a flexible spatial model that distinguishes between passive and active restoration suitability. The tool was applied to identify high-priority locations for mangrove, saltmarsh, and seagrass restoration across different scenarios. Results indicate substantial potential for BCE restoration in Victoria, with 33,253 ha of suitable area identified, mostly (>97%) on public land, which aligned with the selection criteria used in the tool. Restoration opportunities are concentrated in bays and estuaries where historical losses have been significant. The mapped outputs provide a decision-support framework for regional restoration planning, while the tool itself can be adapted to other geographies. By integrating multiple spatial criteria and distinguishing between passive and active restoration, our approach offers a new method for targeting BCE restoration and informing resource allocation. The identified restoration potential will also require collaboration with coastal managers and communities, and consideration of socio-economic factors. With further refinements, such as incorporating multi-criteria decision analysis techniques, GIS-based tools can help catalyse strategic blue carbon investments and contribute to climate change mitigation and adaptation goals at different spatial scales. This study highlights the value of spatial identification for BCE restoration and provides a transferable framework for other regions.

Asunto(s)

Carbono , Cambio Climático , Conservación de los Recursos Naturales , Ecosistema , Carbono/química , Técnicas de Apoyo para la Decisión , Humedales , Sistemas de Información Geográfica , Victoria

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Respiratory infections are a major health burden worldwide. Respiratory syncytial virus (RSV) is among the leading causes of hospitalization in both young children and older adults. The onset of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic and the public health response had a profound impact on the normal seasonal outbreaks of other respiratory viruses. However, little is known about how a prior respiratory virus infection impacts SARS-CoV-2 disease outcomes. In this study, we examine the impact of a previous RSV infection on the disease severity of a subsequent SARS-CoV-2 challenge in BALB/c mice. Mice infected with RSV, followed by a SARS-CoV-2 challenge, 30 days later, exhibited decreased weight loss and increased survival as compared to control groups. Our results suggest a prior RSV infection can provide protection against a subsequent SARS-CoV-2 infection. IMPORTANCE: Severe acute respiratory syndrome coronavirus 2 and respiratory syncytial virus are respiratory viruses that are a major health burden worldwide. Severe acute respiratory syndrome coronavirus 2 and respiratory syncytial virus frequently have peak seasonal outbreaks during the winter months, and are capable of causing severe respiratory disease, often leading to hospitalization. The 2019 pandemic brought attention to the importance of understanding how co-circulating viruses can impact the disease severity of other respiratory viruses. It is known that many hospitalized patients are undergoing multiple viral infections at once, yet not much has been studied to understand the impact this has on other respiratory viruses or patients. How co-circulating viruses impact one another can provide critical knowledge for future interventions of hospitalized patients and potential vaccination strategies.

Asunto(s)

COVID-19 , Ratones Endogámicos BALB C , Infecciones por Virus Sincitial Respiratorio , SARS-CoV-2 , Animales , Infecciones por Virus Sincitial Respiratorio/prevención & control , Infecciones por Virus Sincitial Respiratorio/inmunología , Infecciones por Virus Sincitial Respiratorio/virología , Ratones , COVID-19/prevención & control , COVID-19/virología , SARS-CoV-2/inmunología , Femenino , Humanos , Modelos Animales de Enfermedad , Virus Sincitiales Respiratorios/fisiología , Virus Sincitiales Respiratorios/inmunología

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This research explored baby boomer gay men's experiences with primary healthcare and their perspectives of future long-term care. Baby boomer gay men's perspectives about primary healthcare remain understudied in the United States. A descriptive qualitative study was conducted with 30 baby boomer men in the Southwest USA. We used semi-structured interviews to assess participants' initiation and maintenance of primary healthcare, disclosure of sexual orientation to providers, and perspectives about future healthcare needs, including long-term care. Data were analyzed with a latent thematic analysis. We found baby boomer gay men anticipate discrimination because of their sexual orientation whenever they establish healthcare with new providers. Participants identified circumstantial comfort in the new healthcare setting as a key motivator to disclose their sexual orientation. Thus, baby boomer gay men specifically sought gay or gay-friendly healthcare providers to ease the burden of managing disclosure and to permit free discussion of their sexual orientation and healthcare needs. Participants faced recurring anticipation of rejection and discrimination from healthcare providers, which extends to their perceptions of current healthcare encounters and future long-term care placement. Healthcare providers would benefit from understanding the practice implications of this dynamic. Future research on primary healthcare inclusivity is needed.

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Despite advancements in treating cutaneous melanoma, patients with acral and mucosal (A/M) melanomas still have limited therapeutic options and poor prognoses. We analyzed 156 melanomas (101 cutaneous, 28 acral, and 27 mucosal) using the Foundation One cancer-gene specific clinical testing platform and identified new, potentially targetable genomic alterations (GAs) in specific anatomic sites of A/M melanomas. Using novel pre-clinical models of A/M melanoma, we demonstrate that several GAs and corresponding oncogenic pathways associated with cutaneous melanomas are similarly targetable in A/M melanomas. Other alterations, including MYC and CRKL amplifications, were unique to A/M melanomas and susceptible to indirect targeting using the BRD4 inhibitor JQ1 or Src/ABL inhibitor dasatinib, respectively. We further identified new, actionable A/M-specific alterations, including an inactivating NF2 fusion in a mucosal melanoma responsive to dasatinib in vivo. Our study highlights new molecular differences between cutaneous and A/M melanomas, and across different anatomic sites within A/M, which may change clinical testing and treatment paradigms for these rare melanomas.

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Introduction: The Pediatric Surviving Sepsis Campaign supports the implementation of automated tools for early sepsis recognition. In 2019 the C.S. Mott Children's Hospital Pediatric Intensive Care Unit deployed an electronic medical record (EMR)-based screening for early recognition and treatment of sepsis. Materials and Methods: We analyzed all automated primary sepsis alerts, secondary screens, and bedside huddles from November 2019 to January 2020 (Cohort 1) and from November 2020 to January 2021 (Cohort 2) to identify barriers and facilitators for the use of this tool. We distributed surveys to frontline providers to gather feedback on end-user experience. Results: In Cohort 1, 895 primary alerts were triggered, yielding 503 completed secondary screens and 40 bedside huddles. In Cohort 2, 925 primary alerts were triggered, yielding 532 completed secondary screens and 12 bedside huddles. Surveys assessing end-user experience identified the following facilitators: (1) 73% of nurses endorsed the bedside huddle as value added; (2) 74% of medical providers agreed the bedside huddle increased the likelihood of interventions. The greatest barriers to successful implementation included the (1) overall large number of primary alerts from the automated tool and (2) rate of false alerts, many due to routine respiratory therapy interventions. Discussion: Our data suggests that the successful implementation of EMR-based sepsis screening tools requires countermeasures focusing on 3 key drivers for change: education, technology, and patient safety. Conclusion: While both medical providers and bedside nurses found merit in our EMR-based sepsis early recognition system, continued refinement is necessary to avoid sepsis alert fatigue.

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Neural circuits governing all motor behaviors in vertebrates rely on the proper development of motor neurons and their precise targeting of limb muscles. Transcription factors are essential for motor neuron development, regulating their specification, migration, and axonal targeting. While transcriptional regulation of the early stages of motor neuron specification is well-established, much less is known about the role of transcription factors in the later stages of maturation and terminal arborization. Defining the molecular mechanisms of these later stages is critical for elucidating how motor circuits are constructed. Here, we demonstrate that the transcription factor Nuclear Factor-IA (NFIA) is required for motor neuron positioning, axonal branching, and neuromuscular junction formation. Moreover, we find that NFIA is required for proper mitochondrial function and ATP production, providing a new and important link between transcription factors and metabolism during motor neuron development. Together, these findings underscore the critical role of NFIA in instructing the assembly of spinal circuits for movement.

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Cancer cells exhibit rewired transcriptional regulatory networks that promote tumor growth and survival. However, the mechanisms underlying the formation of these pathological networks remain poorly understood. Through a pan-cancer epigenomic analysis, we found that primate-specific endogenous retroviruses (ERVs) are a rich source of enhancers displaying cancer-specific activity. In colorectal cancer and other epithelial tumors, oncogenic MAPK/AP1 signaling drives the activation of enhancers derived from the primate-specific ERV family LTR10. Functional studies in colorectal cancer cells revealed that LTR10 elements regulate tumor-specific expression of multiple genes associated with tumorigenesis, such as ATG12 and XRCC4. Within the human population, individual LTR10 elements exhibit germline and somatic structural variation resulting from a highly mutable internal tandem repeat region, which affects AP1 binding activity. Our findings reveal that ERV-derived enhancers contribute to transcriptional dysregulation in response to oncogenic signaling and shape the evolution of cancer-specific regulatory networks.

Asunto(s)

Neoplasias Colorrectales , Retrovirus Endógenos , Regulación Neoplásica de la Expresión Génica , Transducción de Señal , Humanos , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/virología , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/metabolismo , Retrovirus Endógenos/genética , Elementos de Facilitación Genéticos , Línea Celular Tumoral , Transcripción Genética , Animales , Carcinogénesis/genética , Redes Reguladoras de Genes

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Pediatric foot development throughout childhood and adolescence can present a diagnostic dilemma for radiologists because imaging appearances may be confused with pathology. Understanding pediatric foot development and anatomical variants, such as accessory ossification centers, is essential to interpret musculoskeletal imaging in children correctly, particularly because many of these variants are incidental but others can be symptomatic. We first briefly review foot embryology. After describing common accessory ossification centers of the foot, we explain the different patterns of foot maturation with attention to irregular ossification and bone marrow development. Common pediatric foot variants and pathology are described, such as tarsal coalitions and fifth metatarsal base fractures. We also discuss pediatric foot alignment and various childhood foot alignment deformities.

Asunto(s)

Pie , Humanos , Niño , Pie/diagnóstico por imagen , Pie/anatomía & histología , Adolescente , Deformidades Congénitas del Pie/diagnóstico por imagen , Preescolar , Diagnóstico por Imagen/métodos , Deformidades del Pie/diagnóstico por imagen

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PURPOSE: In this single-institution phase II investigator-initiated study, we assessed the ability of MAPK and VEGF pathway blockade to overcome resistance to immunotherapy in microsatellite-stable metastatic colorectal cancer (MSS mCRC). PATIENTS AND METHODS: Patients with MSS, BRAF wild-type mCRC who progressed on ≥2 prior lines of therapy received pembrolizumab, binimetinib, and bevacizumab until disease progression or unacceptable toxicity. After a safety run-in, patients were randomized to a 7-day run-in of binimetinib or simultaneous initiation of all study drugs, to explore whether MEK inhibition may increase tumor immunogenicity. The primary endpoint was objective response rate (ORR) in all patients combined (by Response Evaluation Criteria in Solid Tumors v1.1). RESULTS: Fifty patients received study drug treatment; 54% were male with a median age of 55 years (range, 31-79). The primary endpoint, ORR, was 12.0% [95% confidence interval (CI) 4.5%-24.3%], which was not statistically different than the historical control data of 5% (P = 0.038, exceeding prespecified threshold of 0.025). The disease control rate was 70.0% (95% CI, 55.4%-82.1%), the median progression-free survival 5.9 months (95% CI, 4.2-8.7 months), and the median overall survival 9.3 months (95% CI, 6.7-12.2 months). No difference in efficacy was observed between the randomized cohorts. Grade 3 and 4 adverse events were observed in 56% and 8% of patients, respectively; the most common were rash (12%) and increased aspartate aminotransferase (12%). CONCLUSIONS: Pembrolizumab, binimetinib, and bevacizumab failed to meet its primary endpoint of higher ORR compared with historical control data, demonstrated a high disease control rate, and demonstrated acceptable tolerability in refractory MSS mCRC.

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Anticuerpos Monoclonales Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica , Bencimidazoles , Bevacizumab , Neoplasias Colorrectales , Humanos , Masculino , Femenino , Persona de Mediana Edad , Bevacizumab/administración & dosificación , Bevacizumab/uso terapéutico , Bevacizumab/efectos adversos , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/mortalidad , Anciano , Anticuerpos Monoclonales Humanizados/administración & dosificación , Anticuerpos Monoclonales Humanizados/efectos adversos , Bencimidazoles/administración & dosificación , Bencimidazoles/uso terapéutico , Bencimidazoles/efectos adversos , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Resistencia a Antineoplásicos/genética , Repeticiones de Microsatélite , Resultado del Tratamiento

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Diversidad Cultural , Capacitismo , Diversidad, Equidad e Inclusión , Enfermeras y Enfermeros , Humanos , Personas con Discapacidad , Inclusión Social

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Purpose: Adenoid cystic carcinoma (ACC) is a rare malignancy accounting for 1% of all head and neck cancers. Treatment for ACC has its challenges and risks, yet few outcomes studies exist. We present long-term outcomes of patients with ACC of the head and neck treated with proton therapy (PT). Materials and Methods: Under an institutional review board-approved, single-institutional prospective outcomes registry, we reviewed the records of 56 patients with de novo, nonmetastatic ACC of the head and neck treated with PT with definitive (n = 9) or adjuvant PT (n = 47) from June 2007 to December 2021. The median dose to the primary site was 72.6 gray relative biological equivalent (range, 64-74.4) delivered as either once (n = 19) or twice (n = 37) daily treatments. Thirty patients received concurrent chemotherapy. Thirty-one patients received nodal radiation, 30 electively and 1 for nodal involvement. Results: With a median follow-up of 6.2 years (range, 0.9-14.7), the 5-year local-regional control (LRC), disease-free survival, cause-specific survival, and overall survival rates were 88%, 85%, 89%, and 89%, respectively. Intracranial extension (P = .003) and gross residual tumor (P = .0388) were factors associated with LRC rates. While the LRC rate for those with a gross total resection was 96%, those with subtotal resection or biopsy alone were 81% and 76%, respectively. The 5-year cumulative incidence of clinically significant grade ≥3 toxicity was 15%, and the crude incidence at the most recent follow-up was 23% (n = 13). Conclusion: This is the largest sample size with the longest median follow-up to date of patients with ACC treated with PT. PT can provide excellent disease control for ACC of the head and neck with acceptable toxicity. T4 disease, intracranial involvement, and gross residual disease at the time of PT following either biopsy or subtotal resection were significant prognostic features for worse outcomes.

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Fisheries management agencies in the U.S. Caribbean are currently taking steps into transitioning from a single species approach to one that includes Ecosystem Based Fisheries Management (EBFM) considerations. In this study, we developed and analyzed stakeholder-driven conceptual models with seven different stakeholder groups in Puerto Rico and the US Virgin Islands to assess and compare their perceptions of the fishery ecosystem. Conceptual models were developed for each stakeholder group during 29 separate workshops involving a total of 236 participants representing Commercial Fishers, Managers, Academics, Local Businesses, Environmental NGOs, and the Caribbean Fishery Management Council (CFMC) District Advisory Panels (DAPs) and Scientific and Statistical Committee (SSC). Non-Metric Multidimensional Scaling (nMDS) and two-mode social network analysis were used to investigate differences and similarities between stakeholder groups as well as to identify priority ecosystem elements and threats. Results show important variations between stakeholders and islands in terms of their perceived importance of ecosystem components and relationships, which supports the need for collaborative approaches and co-production of knowledge in the United States (U.S.) Caribbean region. Despite this variation, important areas of common concern among stakeholders were identified such as: habitat integrity (e.g., coral reefs), water quality, and influence of recreational fisheries and tourism on marine ecosystems. Findings of this study support the use of stakeholder-driven conceptual models as effective tools to guide decision-making, aid prioritization of data collection, and increase collaboration and cooperation among stakeholders in the context of fisheries management.

Asunto(s)

Conservación de los Recursos Naturales , Ecosistema , Explotaciones Pesqueras , Región del Caribe , Conservación de los Recursos Naturales/métodos , Puerto Rico , Islas Virgenes de los Estados Unidos , Humanos , Modelos Teóricos , Estados Unidos , Animales , Participación de los Interesados

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Managing coastal wetlands is one of the most promising activities to reduce atmospheric greenhouse gases, and it also contributes to meeting the United Nations Sustainable Development Goals. One of the options is through blue carbon projects, in which mangroves, saltmarshes, and seagrass are managed to increase carbon sequestration and reduce greenhouse gas emissions. However, other tidal wetlands align with the characteristics of blue carbon. These wetlands are called tidal freshwater wetlands in the United States, supratidal wetlands in Australia, transitional forests in Southeast Asia, and estuarine forests in South Africa. They have similar or larger potential for atmospheric carbon sequestration and emission reductions than the currently considered blue carbon ecosystems and have been highly exploited. In the present article, we suggest that all wetlands directly or indirectly influenced by tides should be considered blue carbon. Their protection and restoration through carbon offsets could reduce emissions while providing multiple cobenefits, including biodiversity.

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INTRODUCTION: Measuring cortisol during military training offers insights into physiological responses to stress. We attempted precisely timed, cortisol awakening response (CAR) and pre-sleep cortisol (PSC), and diurnal slope (peak morning minus evening cortisol), during a British Army exercise. We aimed to understand cortisol dynamics and evaluate the feasibility of CAR and PSC in this environment. METHOD: Setting: high-intensity, 10-day infantry exercise. Participants: regular infantry soldiers exercising (EX, n=25) or headquarters-based (HQ, n=6). Participants undertook PSC and WAKE and WAKE+30 min samples after 1-2 days, 5-6 days and 9-10 days. Wrist-worn GENEActiv accelerometers were used to assess sleep duration in EX only. Samples taken ±15 min from prespecified time points were deemed adherent. Validated questionnaires were used to measure resilience and perceived stress. Cortisol and cortisone were measured simultaneously by liquid chromatography tandem mass spectrometry. RESULTS: From adherent participants' samples, CAR was positive and tended to decrease as the exercise progressed. From all available data, HQ demonstrated greater diurnal slope than EX (F=7.68, p=0.02), reflecting higher morning cortisol (F=4.72, p=0.038) and lower PSC (p=0.04). No differences were seen in cortisol:cortisone ratio. 26.1% of CAR samples were adherent, with moderately strong associations between adherence and stress (r=0.41, p=0.009) but no association between adherence and day of exercise (χ2=0.27, p=0.8), sleep duration (r=-0.112, p=0.43) or resilience (r=-0.79, p=0.75). Test-retest reliability ratings for CAR were Cronbach's α of 0.48, -11.7 and 0.34 for the beginning, middle and end of the exercise, respectively. CONCLUSIONS: We observed a reduction in morning cortisol and decreased diurnal slope during a high-intensity military exercise, compared with the HQ comparator cohort in whom diurnal slope was preserved. A carefully timed CAR was not feasible in this setting.

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The adsorption of foulants on photocatalytic nanoparticles can suppress their reactivity in water treatment applications by scavenging reactive species at the photocatalyst surface, screening light, or competing for surface sites. These inhibitory effects are commonly modeled using the Langmuir-Hinshelwood model, assuming that adsorbed layer compositions follow Langmuirian (equilibrium) competitive adsorption. However, this assumption has not been evaluated in complex mixtures of foulants. This study evaluates the photoreactivity of titanium dioxide (TiO2) nanoparticles toward a target compound, phenol, in the presence of two classes of foulants ─ natural organic matter (NOM) and a protein, bovine serum albumin (BSA) ─ and mixtures of the two. Langmuir adsorption models predict that BSA should strongly influence the nanoparticle photoreactivity because of its higher adsorption affinity relative to phenol and NOM. However, model evaluation of the experimental phenol decay rates suggested that neither the phenol nor foulant surface coverages are governed by Langmuirian competitive adsorption. Rather, a reactivity model incorporating kinetic predictions of adsorbed layer compositions (favoring NOM adsorption) outperformed Langmuirian models in providing accurate, unbiased predictions of phenol degradation rates. This research emphasizes the importance of using first-principles models that account for adsorption kinetics when assumptions of equilibrium adsorption do not apply.

Asunto(s)

Nanopartículas , Adsorción , Cinética , Nanopartículas/química , Albúmina Sérica Bovina/química , Titanio/química