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Tensions arise with regard to appropriate research preparation and dissertation experiences for students who have as a career goal the conducting of context-based research to solve problems of practice (Hochbein & Perry, 2013; Shulman, Golde, Conklin Bueschel, & Garabedian, 2006). Schön (1995) describes "technical rationality[,] the prevailing epistemology built into the research university" (p. 27), as a primary impediment to programs that attempt to develop practitioner scholars. In this paper, we define technical rationality and explore the epistemological challenges it presents to faculty. Next, we describe a critical incident illustrating how conflicting epistemologies between programs and graduate schools impact students and faculty. Finally, we make recommendations for policies and practices that could better support doctoral work conducted from a range of epistemological approaches.

The global positioning system (GPS) must be familiar to every user of a smartphone as a way to locate one's position on Earth to within several meters. The constellation of orbiting atomic clocks equipped with radio transmitters allows receivers on Earth to determine their own position by measuring the travel times of radio signals from multiple satellites. A physics laboratory for an upper-level majors course involving GPS signals might be assumed to focus on relativistic effects (either special or general), but this paper demonstrates that the ultra-precise time signal from a GPS receiver can be used for a variety of data collection purposes.

Multi-principal element alloy (MPEA) 3D printing is challenging due to the tradeoff between achieving high-temperature and sufficient heating zone. Here, the authors report an ultrahigh-temperature melt printing method that can achieve rapid melting and uniform elemental mixing for MPEA fabrication.

Abstract The muscle fiber ultrastructure in Idiopathic Inflammatory Myopathies (IIM) has been scarcely explored, especially in Inclusion Body Myositis. The aim of this study was to implement the Scanning Electron Microscopy (SEM) in a small cohort of IIM patients, together with the characterization of immunological profile for a better understanding of the pathophysiology. For immunological profile characterization, we identified the presence of autoantibodies (Ro-52, OJ, EJ, PL7, PL12, SRP, Jo-1, PMScl75, PMScl100, Ku, SAE1, NXP2, MDA5, TIF1γ, Mi-2α, Mi-2β) and quantified cytokines (IL-1β, IFN-α2, IFN-γ, TNF-α, IL-6, IL-10, IL-12p70, IL-17A, IL-18, IL-23, IL-33) and chemokines (CCL2, CXCL8). The histological analysis was made by hematoxylin–eosin staining while the muscle fiber ultrastructure was characterized by SEM. We observed changes in the morphology and structure of the muscle fiber according to muscle strength and muscle enzymes. We were able to find and describe muscle fiber ultrastructure with marked irregularities, porosities, disruption in the linearity and integrity of the fascicle, more evident in patients with increased serum levels of muscle enzymes and diminished muscle strength. Despite the scarce reports about the use of SEM as a tool in all clinical phenotypes of IIM, our work provides an excellent opportunity to discuss and reframe the clinical usefulness of SEM in the diagnostic approach of IIM.

Abstract Pericardial effusions requiring pericardiocentesis have multiple causes that vary among geographical regions and health contexts. This procedure can be performed for diagnostic or therapeutic indications. The purpose of this study was to identify the principal causes of pericardial effusions and indications for pericardiocentesis, exploring differences among groups. This was a retrospective case series of patients who underwent pericardiocentesis for pericardial effusion in a single center in Latin America. Demographic, clinical, echocardiographic, and procedural variables were recorded and analyzed. The primary outcome was to determine the causes of pericardial effusions in these patients and the indication (diagnostic, therapeutic, or both). The results are presented in two groups (inflammatory and noninflammatory) according to the cause of the pericardial effusion. One hundred sixteen patients with pericardial effusion underwent pericardiocentesis. The median age was 58 years (IQR 46.2–70.7), and 50% were male. In the noninflammatory pericardial effusion group, there were 61 cases (53%), among which neoplastic pericardial effusion was the most frequent cause (n = 25, 40.9%). In the inflammatory group, there were 55 cases (47%), and the main cause was postpericardiectomy syndrome after cardiac surgery (n = 31, 56.4%). In conclusion, the principal indication for pericardiocentesis was therapeutic (n = 66, 56.8%). Large pericardial effusion without hemodynamic effect of cardiac tamponade was significantly more frequent in the inflammatory group (p = 0.03). The principal cause of pericardial effusion in patients who underwent pericardiocentesis was postpericardiectomy syndrome after cardiac surgery, followed by neoplastic pericardial effusion. Pericardiocentesis is mainly a therapeutic procedure.

This study focused on analyzing and comparing bioactive compounds, specifically phenolics, in the pulp and leaf of Annona muricata (soursop), a crop highly valued in Latin America for its culinary and traditional uses. Methanolic extractions of leaf and pulp were performed for phytochemical screening, high-performance liquid chromatography (HPLC), and measurements of antioxidant capacity. The results confirmed the presence of 15 phenolic compounds in the leaf and 14 in the pulp; these included phenolic acids and flavonoids. Shikimic acid was the main component identified, constituting 85 mg/g of the dry leaf sample and 17.50 mg/g of the dry pulp. The antioxidant capacity was determined using DPPH and FRAP. The percentages of inhibition were 70.93 and 15.10 in the leaf and pulp, respectively. This work expands our knowledge about the compounds present in A. muricata, which may be partly responsible for the known benefits of this plant for human health and nutrition. [ABSTRACT FROM AUTHOR]

Summary: Wood anatomy plays a key role in plants' ability to persist under drought and should therefore predict demography. Plants balance their resource allocation among wood cell types responsible for different functions. However, it remains unclear how these anatomical trade‐offs vary with water availability, and the extent to which they influence demographic rates.We investigated how wood anatomical trade‐offs were related to drought and demographic rates, for seedling communities in four tropical dry forests differing in their aridity indexes (AIs). We measured wood density, as well as vessel, fiber and parenchyma traits of 65 species, and we monitored growth and survival for a 1‐yr period.Two axes defined wood anatomical structure: a fiber‐parenchyma axis and a vessel‐wood density axis. Seedlings in drier sites had larger fiber but lower parenchyma fractions, while in less dry forests, seedlings had the opposite allocation pattern. The fiber–parenchyma trade‐off was unrelated to growth but was positively related to survival, and this later relationship was mediated by the AI.These findings expand our knowledge about the wood anatomical trade‐offs that mediate responses to drought conditions and influence demographic rates, in the seedling layer. This information is needed to anticipate future responses of forests to changing drought conditions. [ABSTRACT FROM AUTHOR]

Tumors have high requirements in terms of nutrients and oxygen. Angiogenesis is the classical mechanism for vessel formation. Tumoral vascularization has the function of nourishing the cancer cells to support tumor growth. Vasculogenic mimicry, a novel intratumoral microcirculation system, alludes to the ability of cancer cells to organize in three-dimensional (3D) channel-like architectures. It also supplies the tumors with nutrients and oxygen. Both mechanisms operate in a coordinated way; however, their functions in breast cancer stem-like cells and their regulation by microRNAs remain elusive. In the present study, we investigated the functional role of microRNA-204 (miR-204) on angiogenesis and vasculogenic mimicry in breast cancer stem-like cells. Using flow cytometry assays, we found that 86.1% of MDA-MB-231 and 92% of Hs-578t breast cancer cells showed the CD44+/CD24− immunophenotype representative of cancer stem-like cells (CSCs). The MDA-MB-231 subpopulation of CSCs exhibited the ability to form mammospheres, as expected. Interestingly, we found that the restoration of miR-204 expression in CSCs significantly inhibited the number and size of the mammospheres. Moreover, we found that MDA-MB-231 and Hs-578t CSCs efficiently undergo angiogenesis and hypoxia-induced vasculogenic mimicry in vitro. The transfection of precursor miR-204 in both CSCs was able to impair the angiogenesis in the HUVEC cell model, which was observed as a diminution in the number of polygons and sprouting cells. Remarkably, miR-204 mimics also resulted in the inhibition of vasculogenic mimicry formation in MDA-MB-231 and Hs-578t CSCs, with a significant reduction in the number of channel-like structures and branch points. Mechanistically, the effects of miR-204 were associated with a diminution of pro-angiogenic VEGFA and β-catenin protein levels. In conclusion, our findings indicated that miR-204 abrogates the angiogenesis and vasculogenic mimicry development in breast cancer stem-like cells, suggesting that it could be a potential tool for breast cancer intervention based on microRNA replacement therapies.

TRIM4Post-Mining is a H2020/RFCS-funded project that brings together a consortium of European experts from industry and academia to develop an integrated information modelling system. This is designed to support decision making and planning during the transition from coal exploitation to a revitalized post-mining landscape, enabling infrastructure development for agricultural and industrial utilization, and contributing to the recovery of energy and materials from coal mining dumps. The smart system will be founded upon a high-resolution spatiotemporal database, utilizing state-of-the-art multi-scale and multi-sensor monitoring technologies that characterize dynamic processes in coal waste dumps related to timely, dependent deformation and geochemical processes. It will integrate efficient methods for operational and post-mining monitoring, comprehensive spatiotemporal data analytics, feature extraction, and predictive modelling; this will allow for the identification of potential contamination areas and the forecasting of geotechnical risks and ground conditions. For the interactive exploration of alternative land-use planning scenarios—in terms of residual risks, technical feasibility, environmental and social impact, and affordability—up-to-date data and models will be embedded in an interactive planning system based on Virtual Reality and Augmented Reality technology, forming a TRIM—a Transition Information Modelling System. This contribution presents the conceptual approach and main constituents, and describes the state-of-the-art and detailed anticipated methodological approach for each of the constituents. This is supported by the presentation of the first results and a discussion of future work. An anticipated second contribution will focus on the main findings, technology readiness and a discussion of future work.

We report our initial experience using Fiber Optic RealShape (FORS), an innovative real-time three-dimensional visualization technology that uses light instead of radiation, to achieve upper extremity (UE) access during fenestrated/branched endovascular aortic aneurysm repair (FBEVAR). An 89-year-old male patient with a type III thoracoabdominal aortic aneurysm, unfit for open aortic repair, underwent FBEVAR. Dual fluoroscopy, intravascular ultrasound, and three-dimensional fusion overlay were used, in addition to FORS. All target artery catheterizations were successfully accomplished using FORS, from UE access, without radiation. Our experience demonstrates that FBEVAR with FORS using UE access can be used for target artery catheterization without radiation.

Background: Q fever is a zoonotic disease produced by infection with Coxiella burnetii which can cause cardiovascular complications such as endocarditis, aneurysms, and vascular graft infections but is uncommon in the absence of exposure to animal reservoirs. Case summary: We present a case of a 64-year-old patient with chronic Q fever infection of an aortic endograft resulting in aorto-enteric fistula. Exposure history reported a recent travel to Mexico and no contact with animals during the stay. Vascular endograft explant was performed and intraoperative findings revealed an abscess cavity along the right anterior abdominal aorta and an aorto-enteric fistula. Extended course doxycycline and hydroxychloroquine were initiated. Due to the diagnostic challenge, we focused on preventing sepsis progression and exposure mitigation to the surgical team. Conclusion: We highlight the atypical presentation of a Q fever aneurysm, outcomes and possible delayed sequelae. A timely diagnosis and high clinical suspicion are paramount to reduce morbidity rate.

Los arabinoxilanos ferulados (AX) forman geles covalentes por acoplamiento oxidativo del ácido ferúlico (AF) generando dímeros (di-AF) y trímeros de AF como estructuras de entrecruzamiento. En esta investigación se estudió el efecto de la gelificación de AX inducida con lacasa o peroxidasa, sobre las estructuras de entrecruzamiento, las características reológicas y la actividad antioxidante de los geles desarrollados. Los geles de AX al 2 % (p/v) formados con peroxidasa registraron valores mayores de di-AF (0.195 µg/g) y módulo elástico (94 Pa) respecto a los obtenidos con lacasa (0.153 µg/g y 79 Pa, respectivamente). Además, los geles inducidos con peroxidasa presentaron mayor actividad antioxidante (13.21 y 3.3 µmol de TEAC/g muestra por método ABTS+ y DPPH, respectivamente) en relación con los generados con lacasa (9.63 y 3.0 µmol de TEAC/g muestra por método ABTS+ y DPPH, respectivamente), lo cual podría atribuirse al mayor contenido de di-AF 8-5’ y 5-5´. Es posible que las diferencias entre estos geles estén relacionadas con el mecanismo de acción de las enzimas utilizadas. La lacasa oxida directamente al AF en AX mientras que, con peroxidasa, el H2O2 realiza esta acción y, por su bajo peso molecular, podría acceder más fácilmente al AF del polisacárido, favoreciendo su entrecruzamiento. DOI: https://doi.org/10.54167/tch.v17i1.1099

Abstract Acute lymphocytic leukemia is the most common type of cancer in pediatric individuals. Glucose regulated protein (GRP78) is an endoplasmic reticulum chaperone that facilitates the folding and assembly of proteins and regulates the unfolded protein response pathway. GRP78 has a role in survival of cancer and metastasis and cell-surface associated GRP78 (sGRP78) is expressed on cancer cells but not in normal cells. Here, we explored the presence of sGRP78 in pediatric B-ALL at diagnosis and investigated the correlation with bona fide markers of leukemia. By using a combination of flow cytometry and high multidimensional analysis, we found a distinctive cluster containing high levels of sGRP78, CD10, CD19, and CXCR4 in bone marrow samples obtained from High-risk leukemia patients, which was absent in the compartment of Standard-risk leukemia. We confirmed that sGRP78+CXCR4+ blood-derived cells were more frequent in High-risk leukemia patients. Finally, we analyzed the dissemination capacity of sGRP78 leukemia cells in a model of xenotransplantation. sGRP78+ cells emigrated to the bone marrow and lymph nodes, maintaining the expression of CXCR4. Testing the presence of sGRP78 and CXCR4 together with conventional markers may help to achieve a better categorization of High and Standard-risk pediatric leukemia at diagnosis.

Previous studies have shown that environmental conditions and plant attributes determine biomass stocks and productivity across multiple tropical forests. However, it is less clear how these factors act at local scales. We evaluated how the spatial variation of soil resource availability (soil nutrient and water content) and plant functional traits determine species biomass stocks and productivity in a Colombian tropical dry forest, based on spatially explicit soil sampling and an intensive plant trait characterization of 89 species in three 1-ha permanent plots with similar climate and floristic composition. Within each plot, we measured nine soil variables and ten functional traits and quantified forest biomass stocks and productivity for 10,161 individual trees in a period of 3 years. The soil resources where species were located and their functional traits had coordinated effects on the spatial distribution of forest biomass stocks across the plots. The highest biomass stocks were concentrated on nutrient-rich soils with low water availability and were dominated by conservative species with dense tissues and low hydraulic failure risk, probably because they are able to better cope with water limitation. Most of the remaining forest biomass stocks were found in nutrient-poor soils with high water availability and were dominated by acquisitive species. Sites with nutrient-rich soils and low water availability increased biomass survival but also mortality; however, the presence of conservative species in these sites also increased biomass survival, decreased mortality, and led to biomass accumulation, probably because their strong and hydraulically secure tissues are able to deal with water limitation for nutrient absorption during dry seasons. Interestingly, soil resources and functional traits had no effects on biomass recruitment. We conclude that strong coordinated effects of soil resources and functional traits determine local biomass processes of tropical dry forests with a central role of conservative trait species types, whereby these species promote community assembly and functioning but are also vulnerable to potential changes in water availability. Thus, conservation and restoration actions should pay special attention to soil and plant functional trait trade-offs to improve management practices in these threatened forests.

Diabetes mellitus (DM) has a high incidence of comorbidities among patients with severe coronavirus disease 2019 (COVID-19). The elevated prevalence of DM in the world population makes it a significant risk factor because diabetic individuals appear to be prone to clinical complications and have increased mortality rates. Here, we review the possible underlying mechanisms involved in DM that led to worse outcomes in COVID-19. The impacts of hyperglycemia side effects, secondary comorbidities, weakened innate and adaptive immunity, chronic inflammation, and poor nutritional status, commonly present in DM, are discussed. The role of the SARS-CoV-2 receptor and its polymorphic variations on higher binding affinity to facilitate viral uptake in people with DM were also considered. Clinical differences between individuals with type 1 DM and type 2 DM affected by COVID-19 and the potential diabetogenic effect of SARS-CoV-2 infection were addressed.