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Abstract Highly sensitive vertically aligned carbon nanotube arrays (VANTAs) interdigitated electrode (IDE) arrays are developed for electrochemical biosensing of two cytokines (i.e., interleukin‐10 (IL‐10) and interferon‐gamma (IFN‐γ)) that are useful for early detection Johne's disease (Bovine Paratuberculosis) in cattle. The high aspect ratio VANTA‐IDEs (50–60 µm in height) are grown through a chemical vapor deposition process from an iron (Fe) catalyst that is lithographically patterned on a silicon wafer with equal finger width and inter‐finger spacing of 25 µm. After functionalization with distinct antibodies the VANTA‐IDEs are capable of selective detection of both IL‐10 and IFN‐γ within an actual biological matrix (i.e., diluted bovine implant supernatant) over concentration ranges of 0.1 to 30 pg mL−1 (limit of detection – LOD: 0.0911 pg mL−1) and 50–500 pg mL−1 (LOD: 24.17 pg mL−1), respectively with a response time of

Abstract Background Vitamin C deficiency, or scurvy, is rare but poses risks for children with poor diets, limited resources, or malabsorption issues. It may also be common in children with restrictive or selective dietary habits in children with global developmental delay, autism spectrum disorder, and physical disabilities. Symptoms include fatigue, irritability, joint and muscle pain, joint swellings, edema, swollen gums, easy bruising, and delayed wound healing. Early recognition and prompt intervention are essential to prevent the progression of symptomatic vitamin C deficiency in children. Case presentation We present a case of a 13-year-old boy with developmental delay secondary to Lennox Gastaut syndrome referred for suspected recurrent, severe, and atypical IgA vasculitis. He presented with irritability, loss of appetite, petechial and ecchymotic lower limb lesions, unilateral gum swelling, severe arthritis, peripheral oedema, severe weight loss, anaemia, and raised inflammatory markers. Multiple investigations were performed before the diagnosis of scurvy was made. A surgical finding of friable gingival tissue with multiple loose teeth, a skin biopsy with follicular hyperkeratosis and extravasated perifollicular red blood cells, and a typical X-ray finding led to the diagnosis of scurvy. Conclusion Scurvy should be given careful consideration as a differential diagnosis in patients presenting with musculoskeletal issues, mucocutaneous complaints, and constitutional symptoms such as malaise, asthenia, irritability, and loss of appetite. A focused and detailed dietary history looking for a lack of good sources of vitamin C can be an easy indicator of this differential. Imaging studies revealing the typical features can also help make the diagnosis. Pathology of the skin revealing pathognomonic features can add to the certainty of the diagnosis. In the absence of all else, the rapid response to treatment with an appropriate dose of vitamin C has a diagnostic and therapeutic role.

Abstract Nitrogen isotope analyses of amino acids (δ15N‐AA) are being increasingly used to decipher trophic dynamics. Interpretation of δ15N‐AA in consumers relies on the assumption that consumer physiological status and nutritional status of prey have negligible influences on the trophic discrimination factor (TDF), hence a constant TDF value is used in trophic position (TP) equations. Recent experiments have shown that this is not always the case and there is also a need to validate derived TP estimates in the field. We take advantage of the uniquely long time series of environmental monitoring data and archived (frozen) samples from the species‐poor Baltic Sea. We analyzed δ15N‐AA in similar sized individuals of cod and in its prey herring from four decades, 1980–2018; including time periods where dramatic reduction in condition status of cod has occurred. We expected that TDF in trophic AAs would increase during periods of poor cod condition, resulting in inflated TP estimates. We found that calculated TP and empirical estimates of TDF (difference in δ15N in trophic AAs between cod and herring) for cod increased in recent decades and that this was linked to condition status, herring (prey) lipid content and the hypoxic state of the ecosystem. Statistically adjusting TP for condition and prey lipid content as well as environmental stress (hypoxia) resulted in lower cod TP which better resembled the observed decrease in herring TP in recent decades. TP calculated from stomach analysis data in cod individuals over the same period showed no trend over time and confirmed that adjusted TP estimates mirror the real dietary TP better than unadjusted. By simultaneously measuring condition/nutritional status in both predator and prey it is possible to adjust for them as confounding variables and decipher actual consumer TP, partly overcoming the issues of unknown and variable TDF‐values. Our study also highlights the importance of including environmental stressors (here hypoxia) when interpreting TP and reconstructing food webs.

Abstract The southeastern United States Coastal Plain ecosystem contains baldcypress (Taxodium distichum) swamps and grass‐dominated marshes. These ecosystems also occurred on the exposed continental shelf during lower sea levels but are rarely preserved due to the mechanically erosive nature of transgression and regression. Two presently marine sites on the northeastern Gulf of Mexico's continental shelf contain well‐preserved woody terrestrial sediments that were the subject of previous studies. This study continues the investigation using geochemical (δ13C, δ15N, δ34S) and palynological characteristics of these formerly terrestrial sediments to determine if swamps and/or marshes existed at the time of deposition. The first site is located ∼20 km southeast of Horn Island, Mississippi (MS) and the core has terrestrial sediments radiocarbon dated to 11,066–10,228 (2σ) calibrated years BP (early Holocene). The second site is the “Alabama Underwater Forest” located ∼13 km south of Gulf Shores, Alabama (AL) and the cores have terrestrial sediments optically stimulated luminescence dated to 63 ka (±10 ka, 2σ) to 72 ka (±16 ka, 2σ) (late Pleistocene). Geochemical results for the MS sediments indicate a swamp‐to‐freshwater marsh transitional series, whereas the AL sediments indicate a swamp‐to‐saltwater marsh transitional series, both supported by palynological results. Further exploration of the geochemical results using linear discriminant analysis, trained with published geochemical data, supports the swamp and marsh interpretations. We conclude that the near‐pristine preservation of these woody deposits is not solely due to physical mechanisms, such as rapid burial, but is also coupled with anoxia‐ and euxinia‐driven biogeochemical reactions promoting wood and woody debris preservation in swamp and marsh environments.

Objectives Following heat illness, a return to activity may require passing a heat tolerance test (HTT). However, there are several logistical limitations to the widespread use of the HTT. Thus, it would be advantageous to develop a test that could be conducted in a thermoneutral (~22°C) environment to predict heat tolerance status. The purpose of the current study was to determine the sensitivity and specificity of using the criteria of a heart rate (HR) ≥130 bpm following 30 min of thermoneutral exercise in detecting heat-intolerant and heat-tolerant individuals. Material and Methods Sixty-five subjects visited the lab on 3 separate days. The first visit consisted of completing a maximal oxygen uptake (VO2 max) test to assess cardiovascular fitness. For lab visits 2 and 3, subjects randomly completed a 2-hour walking treadmill test in either a hot (40°C, 40% relative humidity [RH]) or thermoneutral (22°C, 40% RH) environment. Results Forty-eight subjects were classified as heat-intolerant and 17 subjects as heat-tolerant. Using the criterion of a HR ≥130 bpm at 30 min of exercise in the thermoneutral environment, specificity (54%) and sensitivity (100%) of passing the HTT was calculated. Secondary analysis using multiple regression revealed 3 significant variables for predicting ending HR during the HTT. They were: 1) absolute VO2 max (l/min), 2) age, and 3) HR at 30 min of exercise during thermoneutral exercise. Conclusions Exercise in a thermoneutral environment had a positive predictive value of 100%, thus, if a subject has a HR ≥130 bpm at 30 min of exercise in a thermoneutral environment, they are very likely to fail a subsequent 2-hour HTT in the heat and be classified as heat-intolerant. Therefore, prior screening has the potential to save time and money, along with providing safety to a heat-intolerant subject. Int J Occup Med Environ Health. 2023;36(2):192–200

Food allergy is a global health problem affecting up to 10% of the world population. Accurate diagnosis of food allergies, however, is still a major challenge in medical offices and for patients seeking alternative avenues of diagnosis. A flawless test to confirm or rule out a food allergy does not exist. The lack of optimum testing methods to establish precise clinical correlations remains a major obstacle to effective treatment. Certain IgE measurement methods, including component testing, have received FDA clearance, but they have been used primarily as an analytical tool and not to establish clinical correlations. Most allergy tests are still carried out within the laboratory, and skin tests outside a laboratory setting that are used for food allergy diagnosis rely on non-standardized allergens, according to the FDA definition. Epitope mapping and basophil activation test (BAT) have recently been proposed as a means of establishing better clinical correlations. Yet neither have received FDA clearance for widespread distribution. Of the two methods, the BAT has the advantage of being a functional assay. Over the past few years, several large private practice groups in the United States, have developed BAT as a clinical assay and have started using it in patient care. Given this clinical experience, the vast number of papers published on BAT (more than 1,400 as of 2022) and the trend toward increasing FDA regulation, it is essential to understand the roadmap for regulatory clearance of this assay.

In this introduction to the Special Section 'Laboratory Times', the editors argue that a focused body of scholarship at the intersection of time and the laboratory has yet to materialize. To contextualize the papers that comprise the Special Section, we survey the role of the lab within time studies, as well as the place of temporality within Science and Technology Studies (STS). We show how time is made to structure and shape scientific practice and how scientists work with and create time to suit the frames and needs of experimentation. While one might expect to find as many forms of scientific time as there are branches of science, the specific temporalities of bench science have been largely overlooked by scholars. We introduce the arguments of the papers in this Special Section - observing their shared interest in the ways that time is materialized, negotiated and produced in laboratory settings. We conclude by imagining a future in which a research trajectory focused on 'Laboratory TImes' brings scholars in time studies and STS further into conversation. [ABSTRACT FROM AUTHOR]

Stone consolidants have been used in conservation practices for decades, with an increasingly interdisciplinary scientific attention to their composition and performance. This article is an ethnographic account of the process of testing a new consolidant's efficacy, drawn from fieldwork and interviews with scientists and heritage professionals involved in a European project in 2013. I illustrate, in line with prior scholarship on laboratory time, how time is a central tool of laboratory control, which must be managed to produce evidence of consolidant efficacy. Yet the 'fast time' of controlled experimental conditions is also suspect for those working in the field of heritage. By tracing the temporal tensions between scientific evidence making, laboratory practice and heritage practitioners' values, I illustrate that the project of materially fixing stone in time means intervening on heritage futures. [ABSTRACT FROM AUTHOR]

Renal cell carcinoma is rarely described in paediatric patients with tuberous sclerosis complex. This report describes a case of an 11-year-old male with tuberous sclerosis-associated renal cell carcinoma.

Contaminant monitoring in biota is important for determining environmental status and to detect or prioritize action on hazardous substances. Predators higher up a food chain are often used for monitoring of contaminants that bioaccumulate. However, it is not always possible to find higher predators that are both abundant and have a wide distribution for national or international contaminant monitoring. Great cormorants (Phalocrocorax carbo) are a widespread and increasingly common top predator of fish in fresh, brackish and salt water. We evaluate the suitability of great cormorant eggs as a matrix for contaminant monitoring by using stable isotopes of carbon, nitrogen and sulfur. Despite the fact that cormorants are migratory, egg isotope values showed a significant separation between five breeding colonies in Sweden (1 fresh water lake, 3 Baltic sites and 1 marine site). This high degree of separation indicates that eggs are primarily produced using local resources (not stored body resources) and that contaminants (mercury concentrations in this study) measured in eggs likely reflect levels in fish prey caught close to the breeding area. Compound specific stable isotope analysis was used to estimate cormorant trophic position (TP) and concentrations of mercury in eggs were positively related to TP. The results show that a multi-isotope approach, combined with good ecological diet knowledge allow for meaningful and comparative interpretation of mercury concentrations in biota and that great cormorant eggs appear a suitable matrix to measure locally derived and maternally transferred contaminants.

Unlike cadaver donation in the West, which has to a large degree maintained the anonymity of the body used to teach medical students, the Taiwanese Tzu Chi Buddhist Silent Mentor programme at the centre of this article foregrounds the identity of the trai

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Fakes have become a matter of concern across global health. Commissioning inquiry into presumed fake practices in global health requires both a pre-existing sense of what would constitute real provision and a suspicion that it is not being offered. In this Position Piece, we analyse the research methods being used to identify and reveal other—presumed—fakes in global health provision. We put forward the concept of the ‘second-order fake’—the fake that is used to reveal a fake—to draw attention to the methodological politics at stake in the use of the fake. By reviewing historical cases of the creation of methods of deception, we analyse the assumptions they bring into global health from other disciplines. We foreground the promises of revelation that are embedded in probes that rely on fakes to uncover fakes. We suggest that despite the growing prevalence of methods which themselves deploy fakes to find fakes, these techniques bring us no closer to understanding the lived ambiguities of everyday practices of fakery.

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Abstract Background Although medical school programs oriented toward postgraduate specialty training have the potential to reduce the duration and cost of medical school for US medical students, success depends on the ability of students to predict their postgraduate specialties. It is clear that first-year choices are poorly predictive, but it is not known when predictions become sufficiently reliable to support specialty-oriented learning programs. We therefore examined the predictive value of specialty preferences expressed at the ends of the first, second and third years of medical school and asked whether concurrent expressions of confidence in choices improved predictive ability. We also investigated the possibility that discrepancies between predicted and actual postgraduate specialty training were related to scores on an examination of knowledge in basic biomedical sciences required for US medical school graduation (the United States Medical Licensing Examination (USLME) Step 1 examination). Method We calculated positive and negative predictive values (PPV and NPV, respectively) for specialty choices and the sensitivity and specificity of asking for choices for 634 University of Colorado School of Medicine students who trained in 23 accredited residencies from 2011 through 2015. We examined the effect of confidence in first choices in 609 students, and in 334 students, sought an association between USMLE Step 1 scores and switching from postgraduate training specialties predicted at the end of year 2. Results The PPV of first choices improved from years 1 through 3. NPV was high throughout. PPVs of year 3 first choices ranged from 79% in Anesthesiology to 95% in Psychiatry. Expressions of confidence in first choices did not improve PPV. Sensitivity of asking for first choices increased with time; specificity was consistently high. USLME Step 1 scores were higher for students who ultimately trained in specialties more competitive than first-choice specialties at the end of year 2. Conclusions Specialty-oriented learning programs during medical school must accommodate students who change career plans. The PPV of specialty first choices improves each year, but even year 3 predictions can be inaccurate with potential loss of students from specialty-specific programs. USMLE Step 1 scores appeared to affect career plans expressed at the end of year 2.