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Electric vehicles (EVs) constitute just a fraction of the current U.S. transportation fleet; however, EV market-share is surging. EV adoption reduces on-road transportation greenhouse gas emissions by decoupling transportation services from petroleum, but impacts on air quality and public health depend on the nature and location of vehicle usage and electricity generation. Here, we use a regulatory-grade chemical transport model and an electricity dispatch algorithm to characterize neighborhood-scale (~1 km) air quality and public health benefits and tradeoffs associated with a multi-modal EV transition. We focus on a Chicago-centric regional domain wherein 30% of the on-road transportation fleet is instantaneously electrified and changes in on-road, refueling, and power plant emissions are considered. We find decreases in annual population-weighted domain mean NO2 (-11.84%) and PM2.5 (-2.56%) with concentration reductions of up to-5.1 ppb and-0.97 µg m-3 in urban cores. Conversely, annual population-weighted domain mean MDA8O3 concentrations increase +0.65%, with notable intra-urban changes of up to +2.3 ppb. Despite mixed pollutant concentration outcomes, we find overall positive public health outcomes, largely driven by NO2 decreases that produce mortality reductions that are ~5 times greater in census tracts with disproportionately large non-white populations.

Heavy-duty vehicles (HDVs) disproportionately contribute to the creation of air pollutants and emission of greenhouse gases – with marginalized populations unequally burdened by the impacts of each. Shifting to non-emitting technologies, like electric HDVs (eHDVs) is underway, however, the associated air quality and health implications have not been resolved at equity-relevant scales. Here, we use a neighborhood-scale (~1km) air quality model to evaluate air pollution, public health, and equity implications of a 30% transition of predominantly diesel HDVs to eHDVs over the region surrounding North America’s largest freight hub, Chicago, Illinois. We find decreases in NO2 and PM2.5 but O3 increases, particularly in urban settings. NO2 and PM2.5 decreases reduce premature deaths/yr by ~580 and ~70, respectively, while O3 increases add ~50 deaths/yr. We find the largest pollutant and health benefits in “least White” communities, highlighting the potential for eHDVs to reduce air pollution and health burdens, especially in marginalized communities.

Patients suffering from advanced Parkinson’s disease are treated with deep brain stimulation of the subthalamic nucleus. In addition to favourable effects on movement some patients experience behavioural side effects. The aim of this doctoral research was to attempt to stimulate only the part of the subthalamic nucleus responsible for motor functions. Although the study showed that the motor area could not be strictly divided from non-motor areas, rapid technological progress will allow deep brain stimulation to be further sophisticated, which will lead to a better treatment for patients.

The Lake Michigan Ozone Study 2017 (LMOS 2017) in May and June 2017 enabled study of transport, emissions, and chemical evolution related to ozone air pollution in the Lake Michigan airshed. Two highly instrumented ground sampling sites were part of a wider sampling strategy of aircraft, shipborne, and ground-based mobile sampling. The Zion, Illinois site (on the coast of Lake Michigan, 67 km north of Chicago) was selected to sample higher NOx air parcels having undergone less photochemical processing. The Sheboygan, Wisconsin site (on the coast of Lake Michigan, 211 km north of Chicago) was selected due to its favorable location for observation of photochemically aged plumes during ozone episodes involving southerly winds with lake breeze. The study encountered elevated ozone during three multiday periods. Daytime ozone episode concentrations at Zion were 60 ppb for ozone, 3.8 ppb for NOx, 1.2 ppb for nitric acid, and 8.2 µg/m3 for fine particulate matter. At Sheboygan daytime ozone episode concentrations were 60 ppb for ozone, 2.5 ppb for NOx, and 2.9 ppb for NOy. To facilitate informed use of the LMOS 2017 data repository, we here present comprehensive site description, including airmass influences during high ozone periods of the campaign, overview of meteorological and pollutant measurements, analysis of continuous emission monitor data from nearby large point sources, and characterization of local source impacts from vehicle traffic, large point sources, and rail. Consistent with previous field campaigns and the conceptual model of ozone episodes in the area, trajectories from the southwest, south, and lake breeze trajectories (south or southeast) were overrepresented during pollution episodes. Local source impacts from vehicle traffic, large point sources, and rail were assessed and found to represent less than about 15% of typical concentrations measured. Implications for model-observation comparison and design of future field campaigns are discussed. Implication StatementThe Lake Michigan Ozone Study 2017 (LMOS 2017) was conducted along the western shore of Lake Michigan, and involved two well-instrumented coastal ground sites (Zion, IL, and Sheboygan, WI). LMOS 2017 data is publicly available, and this paper provides detailed site characterization and measurement summary to enable informed use of repository data. Minor local source impacts were detected but were largely confined to nighttime conditions of less interest for ozone episode analysis and modeling. The role of these sites in the wider field campaign and their detailed description facilitates future campaign planning, informed data repository use, and model-observation comparison. Implication Statement The Lake Michigan Ozone Study 2017 (LMOS 2017) was conducted along the western shore of Lake Michigan, and involved two well-instrumented coastal ground sites (Zion, IL, and Sheboygan, WI). LMOS 2017 data is publicly available, and this paper provides detailed site characterization and measurement summary to enable informed use of repository data. Minor local source impacts were detected but were largely confined to nighttime conditions of less interest for ozone episode analysis and modeling. The role of these sites in the wider field campaign and their detailed description facilitates future campaign planning, informed data repository use, and model-observation comparison.

In recent years, there has been an exponential increase in the use of health and sports-related smartphone applications (apps). This is also reflected in App-stores, which are stacked with thousands of health- and sports-apps, with new apps launched each day. These apps have great potential to monitor and support people’s physical activity and health. For users, however, it is difficult to know which app suits their needs. In this paper, we present an online tool that supports the decision-making process for choosing an appropriate app. We constructed and validated a screening instrument to assess app content quality, together with the assessment of users’ needs. Both served as input for building the tool through various iterations with prototypes and user tests. This resulted in an online tool which relies on app content quality scores to match the users’ needs with apps that score high in the screening instrument on those particular needs. Users can add new apps to the database via the screening instrument, making the tool self supportive and future proof. A feedback loop allows users to give feedback on the recommended app and how well it meets their needs. This feedback is added to the database and used in future filtering and recommendations. The principles used can be applied to other areas of sports, physical activity and health to help users to select an app that suits their needs. Potentially increasing the long-term use of apps to monitor and to support physical activity and health.

We evaluate how fine particulate matter (PM2.5) and precursor emissions could be reduced if 17% of electricity generation was replaced with solar photovoltaics (PV) in the Eastern United States. Electricity generation is simulated using GridView, then used to scale electricity-sector emissions of sulfur dioxide (SO2) and nitrogen oxides (NOX) from an existing gridded inventory of air emissions. This approach offers a novel method to leverage advanced electricity simulations with state-of-the-art emissions inventories, without necessitating recalculation of emissions for each facility. The baseline and perturbed emissions are input to the Community Multiscale Air Quality Model (CMAQ version 4.7.1) for a full accounting of time- and space-varying air quality changes associated with the 17% PV scenario. These results offer a high-value opportunity to evaluate the reduced-form AVoided Emissions and geneRation Tool (AVERT), while using AVERT to test the sensitivity of results to changing base-years and levels of solar integration. We find that average NOX and SO2 emissions across the region decrease 20% and 15%, respectively. PM2.5 concentrations decreased on average 4.7% across the Eastern U.S., with nitrate (NO3−) PM2.5 decreasing 3.7% and sulfate (SO42−) PM2.5 decreasing 9.1%. In the five largest cities in the region, we find that the most polluted days show the most significant PM2.5 decrease under the 17% PV generation scenario, and that the greatest benefits are accrued to cities in or near the Ohio River Valley. We find summer health benefits from reduced PM2.5 exposure estimated as 1424 avoided premature deaths (95% Confidence Interval (CI): 284 deaths, 2 732 deaths) or a health savings of $13.1 billion (95% CI: $0.6 billion, $43.9 billion) These results highlight the potential for renewable energy as a tool for air quality managers to support current and future health-based air quality regulations.

Osteoporosis is a common skeletal disorder characterized by low bone mass leading to increased bone fragility and fracture susceptibility. The bone building cells, osteoblasts, are derived from mesenchymal stromal cells (MSCs); however, with increasing age osteogenic differentiation is diminished and more adipocytes are seen in the bone marrow, suggesting a shift in MSC lineage commitment. Identification of specific factors that stimulate osteoblast differentiation from human MSCs may deliver therapeutic targets to treat osteoporosis. The aim of this study was to identify novel genes involved in osteoblast differentiation of human bone marrow-derived MSCs (hMSCs). We identified the gene chloride intracellular channel protein 3 (CLIC3) to be strongly upregulated during MSC-derived osteoblast differentiation. Lentiviral overexpression of CLIC3 in hMSCs caused a 60% increase of matrix mineralization. Conversely, knockdown of CLIC3 in hMSCs using two short-hairpin RNAs (shRNAs) against CLIC3 resulted in a 69% to 76% reduction in CLIC3 mRNA expression, 53% to 37% less alkaline phosphatase (ALP) activity, and 78% to 88% less matrix mineralization compared to scrambled control. Next, we used an in vivo human bone formation model in which hMSCs lentivirally transduced with the CLIC3 overexpression construct were loaded onto a scaffold (hydroxyapatite-tricalcium-phosphate), implanted under the skin of NOD-SCID mice, and analyzed for bone formation 8 weeks later. CLIC3 overexpression led to a 15-fold increase in bone formation (0.33% versus 5.05% bone area relative to scaffold). Using a Clic3-His-tagged pull-down assay and liquid chromatography-mass spectrometry (LS/MS)-based proteomics analysis in lysates of osteogenically differentiated hMSCs, we showed that CLIC3 interacts with NIMA-related kinase 9 (NEK9) and phosphatidylserine synthase 1 (PTDSS1) in vitro, and this finding was supported by immunofluorescent analysis. In addition, inhibition of NEK9 or PTDSS1 gene expression by shRNAs inhibited osteoblast differentiation and mineralization. In conclusion, we successfully identified CLIC3 to be a lineage-specific gene regulating osteoblast differentiation and bone formation through its interaction with NEK9 and PTDSS1. © The Authors. JBMR Plus is published by Wiley Periodicals, Inc. on behalf of the American Society for Bone and Mineral Research.

The aim of this paper is to design and test a smartphone application which supports personalized running experiences for less experienced runners. As a result of a multidisciplinary three-step design approach Inspirun was developed. Inspirun is a personalized running-application for Android smartphones that aims to fill the gap between running on your own (static) schedule, and having a personal trainer that accommodates the schedule to your needs and profile. With the use of GPS and Bluetooth heart rate monitor support, a user's progress gets tracked. The application adjusts the training schedule after each training session, motivating the runner without a real life coach. Results from three user studies are promising; participants were very satisfied with the personalized approach, both in the profiling and de adaptation of their training scheme.

Physical inactivity has become a major public health concern and, consequently, the awareness of striving for a healthy lifestyle has increased. As a result, the popularity of recreational sports, such as running, has increased. Running is known for its low threshold to start and its attractiveness for a heterogeneous group of people. Yet, one can still observe high drop-out rates among (novice) runners. To understand the reasons for drop-out as perceived by runners, we investigate potential reasons to quit running among short distance runners (5 km and 10 km) (n = 898). Data used in this study were drawn from the standardized online Eindhoven Running Survey 2016 (ERS16). Binary logistic regressions were used to investigate the relation between reasons to quit running and different variables like socio-demographic variables, running habits and attitudes, interests, and opinions (AIOs) on running. Our results indicate that, not only people of different gender and age show significant differences in perceived reasons to quit running, also running habits, (e.g., running context and frequency) and AIOs are related to perceived reasons to quit running too. With insights into these related variables, potential drop-out reasons could help health professionals in understanding and lowering drop-out rates among recreational runners.

The scope of technology has expanded towards areas such as sports and vitality, offering significant challenges for engineering designers. However, only little is known about the underlying design and engineering processes used within these fields. Therefore, this paper aims to get an in- depth understanding of these type of processes. During a three-day design competition (Hackathon), three groups of engineers were challenged to develop experience-able prototypes in the field of sports and vitality. Their process was monitored based on the Reflective Transformative Design process (RTD-process) framework, describing the various activities part of the design process. Groups had to keep track of their activities, and six group reflection-sessions were held. Results show that all groups used an open and explorative approach, they frequently swapped between activities, making them able to reflect on their actions. While spending more time on envisioning and creating a clear vision seem to relate to the quality of the design concept., The scope of technology has expanded towards areas such as sports and vitality, offering significant challenges for engineering designers. However, only little is known about the underlying design and engineering processes used within these fields. Therefore, this paper aims to get an in-depth understanding of these type of processes. During a three-day design competition (Hackathon), three groups of engineers were challenged to develop experience-able prototypes in the field of sports and vitality. Their process was monitored based on the Reflective Transformative Design process (RTD-process) framework, describing the various activities part of the design process. Groups had to keep track of their activities, and six group reflection-sessions were held. Results show that all groups used an open and explorative approach, they frequently swapped between activities, making them able to reflect on their actions. While spending more time on envisioning and creating a clear vision seem to relate to the quality of the design concept.

Despite recent progress in genome topology knowledge, the role of repeats, which make up the majority of mammalian genomes, remains elusive. Satellite repeats are highly abundant sequences that cluster around centromeres, attract pericentromeric heterochromatin, and aggregate into nuclear chromocenters. These nuclear landmark structures are assumed to form a repressive compartment in the nucleus to which genes are recruited for silencing. We have designed a strategy for genome-wide identification of pericentromere-associated domains (PADs) in different mouse cell types. The ∼1000 PADs and non-PADs have similar chromatin states in embryonic stem cells, but during lineage commitment, chromocenters progressively associate with constitutively inactive genomic regions at the nuclear periphery. This suggests that PADs are not actively recruited to chromocenters, but that chromocenters are themselves attracted to inactive chromatin compartments. However, we also found that experimentally induced proximity of an active locus to chromocenters was sufficient to cause gene repression. Collectively, our data suggest that rather than driving nuclear organization, pericentromeric satellite repeats mostly co-segregate with inactive genomic regions into nuclear compartments where they can contribute to stable maintenance of the repressed status of proximal chromosomal regions.

Individual and unorganized sports with a health-related focus, such as recreational running, have grown extensively in the last decade. Consistent with this development, there has been an exponential increase in the availability and use of electronic monitoring devices such as smartphone applications (apps) and sports watches. These electronic devices could provide support and monitoring for unorganized runners, who have no access to professional trainers and coaches. The purpose of this paper is to gain insight into the characteristics of event runners who use running-related apps and sports watches. This knowledge is useful from research, design, and marketing perspectives to adequately address unorganized runners' needs, and to support them in healthy and sustainable running through personalized technology. Data used in this study are drawn from the standardized online Eindhoven Running Survey 2014 (ERS14). In total, 2,172 participants in the Half Marathon Eindhoven 2014 completed the questionnaire (a response rate of 40.0%). Binary logistic regressions were used to analyze the impact of socio-demographic variables, running-related variables, and psychographic characteristics on the use of running-related apps and sports watches. Next, consumer profiles were identified. The results indicate that the use of monitoring devices is affected by socio-demographics as well as sports-related and psychographic variables, and this relationship depends on the type of monitoring device. Therefore, distinctive consumer profiles have been developed to provide a tool for designers and manufacturers of electronic running-related devices to better target (unorganized) runners' needs through personalized and differentiated approaches. Apps are more likely to be used by younger, less experienced and involved runners. Hence, apps have the potential to target this group of novice, less trained, and unorganized runners. In contrast, sports watches are more likely to be used by a different group of runners, older and more experienced runners with higher involvement. Although apps and sports watches may potentially promote and stimulate sports participation, these electronic devices do require a more differentiated approach to target specific needs of runners. Considerable efforts in terms of personalization and tailoring have to be made to develop the full potential of these electronic devices as drivers for healthy and sustainable sports participation. ispartof: PLoS One vol:12 issue:7 ispartof: location:United States status: published

Smartphone applicaties zijn niet meer weg te denken uit de samenleving en uit het sport- en beweeglandschap. Ze worden vooral gebruikt om (sport) activiteiten te registreren, maar ook steeds meer om sporters te ondersteunen. Hierdoor komen ook sportprofessionals ermee in aanraking. Maar wat moet er gebeuren om het gebruik en de inzet van apps onder sportprofessionals te vergroten?

De auteurs gaan in dit artikel in op de mogelijkheden van innovatieve technologie in het stimuleren van sport en bewegen en het op maat aanpassen van beweegvriendelijke omgevingen in een stedelijke context. Ze concluderen dat laagdrempelige technologie zoals smartphone applicaties (apps) en wearables veelvuldig worden gebruikt door minder actieve lopers en door vrouwelijke lopers en dat app-gebruikers vaak jonger zijn. De auteurs zien deze mogelijkheden als veelbelovend, maar concluderen ook dat toekomstig onderzoek nodig is om korte- en langetermijneffecten van deze technologie te bevestigen.

Summary Detailed genomic contact maps have revealed that chromosomes are structurally organized in megabase-sized topologically associated domains (TADs) that encompass smaller subTADs. These domains segregate in the nuclear space to form active and inactive nuclear compartments, but cause and consequence of compartmentalization are largely unknown. Here, we combined lacO/lacR binding platforms with allele-specific 4C technologies to track their precise position in the three-dimensional genome upon recruitment of NANOG, SUV39H1, or EZH2. We observed locked genomic loci resistant to spatial repositioning and unlocked loci that could be repositioned to different nuclear subcompartments with distinct chromatin signatures. Focal protein recruitment caused the entire subTAD, but not surrounding regions, to engage in new genomic contacts. Compartment switching was found uncoupled from transcription changes, and the enzymatic modification of histones per se was insufficient for repositioning. Collectively, this suggests that trans-associated factors influence three-dimensional compartmentalization independent of their cis effect on local chromatin composition and activity., Graphical Abstract, Highlights • 4C technology reveals nuclear repositioning of genomic loci upon protein recruitment • Given subTAD can adopt multiple nuclear positions depending on the recruited factor • Switching between nuclear compartments can be uncoupled from transcriptional changes • Histone-modifying SUV39H1 relies on its chromodomain for locus repositioning, Wijchers et al. combine 4C technology with lacO/lacR binding platforms to show that a given genomic locus can adopt multiple nuclear positions depending on the recruited protein. Focal protein recruitment can move an entire subTAD, but repositioning appeared largely unrelated to changes in its chromatin composition and activity.

The hypothalamo-pituitary-adrenal (HPA) axis is involved in stress, depression and anxiety. Controversy exists on HPA axis activation during panic attacks (PAs). We examined whether the HPA axis is involved in the escape or panic-like response in an animal model of PAs induced by electrical stimulation of the dorsolateral periaqueductal gray (dlPAG) in rats. Additionally, rats were also treated with chronic administration of buspirone (BUSP) and escitalopram (ESCIT), respectively; and they were stimulated in the open-field arena for panic-like reaction. Levels of stress hormone corticosterone were measured following 30 min after escape or panic condition. Our results demonstrated that the levels of plasma corticosterone were significantly increased after the induction of escape or panic-like response in comparison with the sham animals. The levels of corticosterone were significantly decreased in the dlPAG stimulated groups after rats were treated chronically with the ESCIT but not the BUSP as compared to the saline treated animals. Importantly, the increase of corticosterone level after escape or panic-like response was paralleled by an increase of neuronal activation of c-Fos in both the parvocellular and magnocellular paraventricular nucleus of the hypothalamus. Moreover, the c-Fos data also showed a decrease in the number of positive cells particularly for the ESCIT as well as the BUSP in comparison with the saline stimulated animals. In conclusion, the present study clearly demonstrated that PA or escape response activates the HPA axis and it remains difficult to anticipate the mechanism underlying HPA axis during PAs and its relationship with 5-HT drugs.

We present an examination of the potential emissions and air quality benefits of shifting freight from truck to rail in the upper Midwestern United States. Using a novel, freight-specific emissions inventory (the Wisconsin Inventory of Freight Emissions, WIFE) and a three-dimensional Eulerian photochemical transport model (the Community Multiscale Air Quality Model, CMAQ), we quantify how specific freight mode choices impact ambient air pollution concentrations. Using WIFE, we developed two modal shift scenarios: one focusing on intraregional freight movements within the Midwest and a second on through-freight movements through the region. Freight truck and rail emissions inventories for each scenario were gridded to a 12 km × 12 km horizontal resolution as input to CMAQ, along with emissions from all other major sectors, and three-dimensional time-varying meteorology from the Weather Research and Forecasting model (WRF). The through-freight scenario reduced monthly mean (January and July) localized concentrations of nitrogen dioxide (NO2) by 28% (-2.33 ppbV) in highway grid cells, and reduced elemental carbon (EC) by 16% (-0.05 μg/m(3)) in highway grid cells. There were corresponding localized increases in railway grid cells of 25% (+0.83 ppbV) for NO2, and 22% (+0.05 μg/m(3)) for EC. The through-freight scenario reduced CO2 emissions 31% compared to baseline trucking. The through-freight scenario yields a July mean change in ground-level ambient PM2.5 and O3 over the central and eastern part of the domain (up to -3%).

[1] The Ozarks Isoprene Experiment (OZIE) was conducted in July 1998 in Missouri, Illinois, Indiana, and Oklahoma. OZIE was designed to investigate the presumed strong isoprene emission rates from the Missouri Ozarks, where there is a high density of oak trees that are efficient isoprene emitters. Ground, balloon, and aircraft measurements were taken over a three-week study period; 0-D and 3-D chemical models were subsequently used to better understand the observed isoprene emissions from the Ozarks and to investigate their potential regional-scale impacts. Leaf-level measurements for two oak tree species yielded normalized average isoprene emission capacities of 66 mgC g−1 h−1, in good agreement with values used in current biogenic emissions models. However, the emission capacities exhibited a temperature dependence that is not captured by commonly used biogenic emission models. Isoprene mixing ratios measured aloft from tethered balloon systems were used to estimate isoprene fluxes. These measurement-derived fluxes agreed with BEIS3 estimates within the relatively large uncertainties in the estimates. Ground-level isoprene mixing ratios exhibited substantial spatial heterogeneity, ranging from

Versimpeling van de werkelijkheid in oneliners is soms nodig, maar leidt niet automatisch tot de noodzakelijke veranderingen waar de zorg om vraagt.

Three anaplastic seminomas of the testis were examined by transmission electron microscopy, and the ultrastructural features are described for comparison with those reported in other seminomas and related neoplasms. It is concluded that anaplastic seminomas are similar ultrastructurally to classic testicular seminomas, extragonadal seminomas, and ovarian dysgerminomas, all of which are less differentiated than spermatocytic seminomas.

OBJECTIVE: To systematically collect clinical data from patients with a proven COVID-19 infection in the Netherlands. DESIGN: Data from 2579 patients with COVID-19 admitted to 10 Dutch centers in the period February to July 2020 are described. The clinical data are based on the WHO COVID case record form (CRF) and supplemented with patient characteristics of which recently an association disease severity has been reported. METHODS: Survival analyses were performed as primary statistical analysis. These Kaplan-Meier curves for time to (early) death (3 weeks) have been determined for pre-morbid patient characteristics and clinical, radiological and laboratory data at hospital admission. RESULTS: Total in-hospital mortality after 3 weeks was 22.2% (95% CI: 20.7% - 23.9%), hospital mortality within 21 days was significantly higher for elderly patients (> 70 years; 35, 0% (95% CI: 32.4% - 37.8%) and patients who died during the 21 days and were admitted to the intensive care (36.5% (95% CI: 32.1% - 41.3%)). Apart from that, in this Dutch population we also see a risk of early death in patients with co-morbidities (such as chronic neurological, nephrological and cardiac disorders and hypertension), and in patients with more home medication and / or with increased urea and creatinine levels. CONCLUSION: Early death due to a COVID-19 infection in the Netherlands appears to be associated with demographic variables (e.g. age), comorbidity (e.g. cardiovascular disease) but also disease char-acteristics at admission.

An ongoing challenge for learning algorithms formulated in the Minimally Adequate Teacher framework is to efficiently obtain counterexamples. In this paper we compare and combine conformance testing and mutation-based fuzzing methods for obtaining counterexamples when learning finite state machine models for the reactive software systems of the Rigorous Exampination of Reactive Systems (RERS) challenge. We have found that for the LTL problems of the challenge the fuzzer provided an independent confirmation that the learning process had been successful, since no additional counterexamples were found. For the reachability problems of the challenge, however, the fuzzer discovered more reachable error states than the learner and tester, albeit in some cases the learner and tester found some that were not discovered by the fuzzer. This leads us to believe that these orthogonal approaches are complementary in the context of model learning., Comment: Submitted to the RERS challenge 2016

To the Editor.— The presence of gastric epithelium has a profound effect on the symptomatology of congenital cysts of foregut derivation. 1 Peptic ulceration with penetration of the trachea has caused death in patients who had dorsal enteric mediastinal cysts that were so epithelialized. 2 We report a case of a thyroglossal cyst containing gastric epithelium as part of its lining. Report of a Case.— A 12-year-old boy was admitted for excision of a lump in the front of his neck that had been present for ten years. A 2-cm mass in the anterior midline of the neck was the only abnormality on examination. This was round and soft and moved upward when the patient swallowed or protruded his tongue. Thyroid function study results were normal. The mass did not concentrate radioiodine. At surgery a cyst was found that was connected to the hyoid bone by a cordlike structure. The