bluuebunny/crossref_metadata_2025_split huggingface dataset:
Low-Order Modeling of Can-Annular Combustors
Authors: Fournier Guillaume J. J. , Meindl Max , Silva Camilo F. , Ghirardo Giulio , Bothien Mirko R. , Polifke Wolfgang 
Published: July 2021

Abstract
Heavy-duty land-based gas turbines are often designed with can-annular combustors, which consist of a set of identical cans, acoustically connected on the upstream side via the compressor plenum, and, downstream, with a small annular gap located at the transition with the first turbine stage. The modeling of this cross-talk area is crucial to predict the thermo-acoustic modes of the system. Thanks to the discrete rotational symmetry, Bloch wave theory can be exploited to reduce the system to a longitudinal combustor with a complex-valued equivalent outlet reflection coefficient, which models the annular gap. The present study reviews existing low-order models based purely on geometrical parameters and compares them to two-dimensional Helmholtz simulations. We demonstrate that the modeling of the gap as a thin annulus is not suited for can-annular combustors and that the Rayleigh conductivity model only gives qualitative agreement. We then propose an extension for the equivalent reflection coefficient that accounts not only for geometrical but also flow parameters, by means of a characteristic length. The proposed model is in excellent agreement with two-dimensional simulations and is able to correctly capture the eigenfrequencies of the system. We then perform a Design of Experiments study that allows us to explore various configurations and build correlations for the characteristic length. Finally, we discuss the validity limits of the proposed low-order modeling approach.
Details of Shrouded Stator Hub Cavity Flow in a Multistage Axial Compressor Part 2: Leakage Flow Characteristics in Stator Wells
Authors: Kamdar Nitya , Lou Fangyuan , Key Nicole L. 
Published: July 2021

Abstract
The flow in shrouded stator cavities can be quite complex with axial, radial, and circumferential variations. As the leakage flow recirculates and is re-injected into the main flow path upstream of the stator, it deteriorates the near-hub flow field and, thus, degrades the overall aerodynamic performance of the compressor. In addition, the windage heating in the cavity can raise thermal-mechanical concerns. Fully understanding the details of the shrouded-hub cavity flow in a multistage environment can enable better hub cavity designs. In the first part of the paper, the influence of the hub leakage flow on compressor performance and its interactions with the primary flow were investigated. While the impact of hub leakage flow on the primary passage is readily available in the open literature, details inside the cavity geometry are scarce due to the difficulties in instrumenting that region for an experiment or modeling the full cavity geometry. To shed light on this topic, the flow physics in the stator cavity inlet and outlet wells are investigated in this paper using a coupled computational fluid dynamics model with the inclusion of the stator cavity wells for the Purdue 3-stage (P3S) axial compressor, which is representative of the rear stages of a high-pressure-compressor in core engines. At the inlet cavity, the presence of at least one pair of vortices influences the trajectory of the cavity leakage flow. The amount of leakage flow also determines the size of the vortical structures, with larger clearances creating a smaller vortex and vice versa. After passing through the labyrinth seals, the leakage flow travels along the stator landing first and then transitions to the rotor drum. In general, a flow path closer to the rotor drum achieves higher circumferential velocity but also exhibits significant temperature rise. A rise in circumferential velocity directly corresponds to a rise in temperature. In addition, the windage heating increases with increasing seal clearance. Furthermore, the inlet well contributes the most to overall windage, nearly 50% of the total windage heating, while the labyrinth seals and outlet well account for very little.
Acoustic-Convective Interference in Transfer Functions of Methane/Hydrogen and Pure Hydrogen Flames
Authors: Æsøy Eirik , Aguilar José G. , Bothien Mirko R. , Worth Nicholas A. , Dawson James R. 
Published: July 2021

Abstract
We investigate the occurrence and source of modulations in the gain and phase of flame transfer functions (FTF) measured in perfectly premixed, bluff body stabilized CH4/H2 and pure H2 flames. The modulations are shown to be caused by flow disturbances originating from the upstream geometry, in particular the grub screws used to center the bluff body, indicative of a more generalized phenomenon of convective wave propagation. Velocity measurements are performed at various locations around the injector dump plane, inside the injector pipe, and in the wake of the bluff body to provide detailed insight into the flow. Peaks corresponding to natural shedding frequencies of the grub screws appear in the unforced velocity spectra and it is found that the magnitude of these convective modes depends on their location. Flame imaging and PIV measurements show that these disturbances do not show up in the mean velocity and flame shape which appear approximately axisymmetric. However, the urms and vrms fields capture a strong asymmetry due to convective disturbances. To further quantify the role of these convective disturbances, hydrodynamic transfer functions are constructed from the forced cold flow, and similar modulations observed in the FTFs are found. A strong correlation is obtained between the two transfer functions, subsequently, the modulations are shown to be centered on the vortex shedding frequency corresponding to the first convective mode. The reason behind the excitation of the first mode is due to a condition that states that for acoustic-convective interaction to be possible, the shedding (convective) frequency needs to be lower than the cutoff frequency of the flame response. This condition is shown to be more relevant for hydrogen flames compared to methane flames due to their shorter flame lengths and thus increased cutoff frequency.
Exercise and Heat Stress: Inflammation and the Iron Regulatory Response
Authors: McKay Alannah K.A. , McCormick Rachel , Tee Nicolin , Peeling Peter 
Published: July 2021

This study determined the impact of heat stress on postexercise inflammation and hepcidin levels. Twelve moderately trained males completed three, 60-min treadmill running sessions under different conditions: (a) COOL, 18 °C with speed maintained at 80% maximum heart rate; (b) HOTHR, 35 °C with speed maintained at 80% maximum heart rate; and (c) HOTPACE, 35 °C completed at the average running speed from the COOL trial. Venous blood samples were collected pre-, post-, and 3-hr postexercise and analyzed for serum ferritin, interleukin-6 (IL-6), and hepcidin concentrations. Average HR was highest during HOTPACE compared with HOTHR and COOL (p < .001). Running speed was slowest in HOTHR compared with COOL and HOTPACE (p < .001). The postexercise increase in IL-6 was greatest during HOTPACE (295%; p = .003). No differences in the IL-6 response immediately postexercise between COOL (115%) and HOTHR (116%) were evident (p = .992). No differences in hepcidin concentrations between the three trials were evident at 3 hr postexercise (p = .407). Findings from this study suggest the IL-6 response to exercise is greatest in hot compared with cool conditions when the absolute running speed was matched. No differences in IL-6 between hot and cool conditions were evident when HR was matched, suggesting the increased physiological strain induced from training at higher intensities in hot environments, rather than the heat per se, is likely responsible for this elevated response. Environmental temperature had no impact on hepcidin levels, indicating that exercising in hot conditions is unlikely to further impact transient alterations in iron regulation, beyond that expected in temperate conditions.
Researcher, Coach Developer, and Coaches’ Perspectives on Learner-Centered Teaching in a Rugby Coach Education Program
Authors: Ciampolini Vitor , Camiré Martin , das Neves Salles William , do Nascimento Juarez Vieira , Milistetd Michel 
Published: July 2021

In the sports coaching field, learner-centered teaching (LCT) has been advocated as a viable approach to increasing learners’ involvement in the learning process. However, implementing LCT is not a simple undertaking as coach developers, and coaches have encountered dilemmas when it comes to shifting to LCT in coach education. This study aimed to investigate how LCT principles were implemented in a rugby coach education program through the perspectives of the researcher, the coach developer, and coaches. Participants included the researcher (i.e., first author), a coach developer, and 10 rugby coaches. The researcher observed three coach education courses, gathered descriptive and reflective field notes, and conducted individual semistructured interviews with both the coach developer and the 10 coaches. Findings shed light on the strategies adopted by the coach developer and the extent to which these strategies aligned with LCT principles. Coaches discussed how they enjoyed their active role in the courses and the approaches used by the coach developer to leverage learning. The discussion highlights the importance of coach developers in facilitating a learning process that is challenging, motivating, and supports coaches throughout the courses.
Rhegmatogenous retinal detachment presentation and surgery in uveitic eyes
Authors: Young-Zvandasara Tafadzwa , Brunner David , Welch Sarah , Sims Joanne L , De Souza Clairton , Cunningham William J , Niederer Rachael L 
Published: July 2021

Background/aimsTo explore the occurrence, uveitis activity, features, rate of proliferative vitreoretinopathy (PVR) and outcomes following rhegmatogenous retinal detachment (RRD) in a large tertiary referral uveitis service.MethodsRetrospective analysis of subjects attending between 2008 and 2019. Multivariate analysis of risk factors for RRD was calculated. Nelson-Aalen plots were used to demonstrate cumulative risk of RRD. Outcomes of RRD surgery and prognostic indicators were analysed.ResultsTwo thousand four hundred and forty-seven (2447) subjects (3516 eyes) with uveitis included. The mean follow-up was 5.7 years (19 767 eye-years); 56 eyes developed a RRD (1.6%). Thirty-two eyes had surgery in our unit. Risk factors for RRD were posterior uveitis or panuveitis (HR 3.386, p<0.001), male gender (HR 2.045, p=0.029) and infectious aetiology (HR 1.942, p=0.044). PVR was present in six (18.8%) eyes at presentation, and a further four (12.5%) developed it after the primary surgery. Final follow-up data showed 16 (50%) moderate or severe visual loss, although 29 (90.6%) had anatomical reattachment without oil in situ.ConclusionsThere is a high rate of RRD in uveitis eyes. This is accompanied by high rates of PVR and redetachment. Anatomical success was high, but visual outcomes remain unpredictable.
Optimal resection rate for lung cancer in the UK: how high should we go?
Authors: Belcher Elizabeth , Mitchell Jenny , Stavroulias Dionisios , Di Chiara Francesco , Rahman Najib 
Published: July 2021

BackgroundThe optimal resection rate for institutions managing early-stage primary lung cancer is not known. Whether the prognosis of patients who do not proceed to operation is determined by their comorbidities for which they were deemed at prohibitively high-operative risk, or disease progression, is uncertain. We investigated the outcomes of patients with early-stage lung cancer who were considered for surgical management.MethodsWe reviewed the outcomes of consecutive patients who were considered for resection of early-stage primary lung cancer at Oxford University Hospitals National Health Service Foundation Trust between 2012 and 2017.ResultsBetween 29 November 2012 and 31 March 2017, 467 consecutive patients underwent resection with curative intent for primary lung cancer (operative group), while 81 patients were deemed resectable but either inoperable or did not wish to proceed to operation (non-operative group). Reason for not proceeding to resection was cardiovascular in 16 patients (19.8%), respiratory in 21 (25.9%), cardiorespiratory in 11 (13.6%), performance status in 8 (9.9%) and patient choice in 25 (30.9%) patients. Sixty-six patients (81.5%) received an alternative radical treatment. Median follow-up was 169 weeks (IQR 119–246 weeks) in the operative group and 118 weeks (IQR 74–167 weeks) in the non-operative group. Median survival of patients with early-stage lung cancer who did not proceed to operation was 2.5 years; median survival of patients undergoing lung cancer resection was undefined (p<0.0001). Lung cancer was documented as directly or indirectly leading to or contributing to death in 40 patients (76.9%). In 11 patients, the cause of death was due to comorbidities (21.2%).ConclusionsPatients turned down for operation in a high-resection rate UK unit have limited survival due to lung cancer progression. We conclude that ‘optimal’ resection rates may not have been reached in the UK even in high-resection rate centres.
Characteristics of pulmonary cryptococcosis in patients with rheumatoid arthritis
Authors: Hosoda Chiaki , Ishiguro Takashi , Uozumi Ryuji , Ueda Miyuki , Takata Naomi , Takayanagi Noboru 
Published: July 2021

Background and objectiveA high frequency of infections complicating rheumatoid arthritis (RA) has been reported due to the immunomodulatory effect of RA or to agents with immunosuppressive effects used in its treatment. We aimed to assess clinical and radiological characteristics of pulmonary cryptococcosis in patients with and without RA.MethodsWe retrospectively reviewed the medical records of 52 patients with pulmonary cryptococcosis and divided them into two groups, those with RA and without RA, and compared clinical characteristics and radiological findings between them.ResultsEleven (21.2%) of the 52 patients had RA. Median follow-up periods were 51.2 (range: 1.1–258.7) months for patients with RA and 19.1 (range: 0.63–246.9) months for patients without RA. Among the patients with RA, 81.8% were women, with a mean age of 68.1 years. Female sex and respiratory comorbidities were significantly more frequent in patients with RA than in patients without RA. Frequencies of concomitant cryptococcal meningitis and respiratory failure were not different between the groups. There were no significant differences in frequency of any radiological findings, locations and number between the two groups. Among patients with RA, all but one responded well to antifungal treatment. During the antifungal treatment course, one (9.1%) patient with RA died of cryptococcosis. Despite continuing antirheumatic drugs, no patients had recurrence of pulmonary cryptococcosis during follow-up.ConclusionOther than some differences in background, there were no clinical, radiological or prognostic differences between the patients with and without RA with pulmonary cryptococcosis. The administration of antirheumatic therapy had no negative effect on the clinical course of antifungal treatment.
Efficacy and safety of high flow nasal oxygen for children with bronchiolitis: systematic review and meta-analysis
Authors: Dafydd Carwyn , Saunders Benjamin J , Kotecha Sarah J , Edwards Martin O 
Published: July 2021

BackgroundTo assess the published evidence to establish the efficacy and safety of high flow oxygen cannula (HFNC) as respiratory support for children up to 24 months of age with bronchiolitis within acute hospital settings.MethodsWe searched eight databases up to March 2021. Studies including children up to 24 months of age with a diagnosis of bronchiolitis recruited to an randomised controlled trial were considered in the full meta-analysis. At least one arm of the study must include HFNC as respiratory support and report at least one of the outcomes of interest. Studies were identified and extracted by two reviewers. Data were analysed using Review Manager V.5.4.ResultsFrom 2943 article titles, 308 full articles were screened for inclusion. 23 studies met the inclusion criteria, 15 were included in the metanalyses. Four studies reported on treatment failure rates when comparing HFNC to standard oxygen therapy (SOT). Data suggests HFNC is superior to SOT (OR 0.45, 95% CI 0.36 to 0.57). Four studies reported on treatment failure rates when comparing HFNC to continuous positive airways pressure (CPAP). No significant difference was found between CPAP and HFNC (OR 1.64, 95% CI 0.96 to 2.79; p=0.07). Four studies report on adverse outcomes when comparing HFNC to SOT. No significant difference was found between HFNC & SOT (OR 1.47, 95% CI 0.54 to 3.99).ConclusionHFNC is superior to SOT in terms of treatment failure and there is no significant difference between HFNC and CPAP in terms of treatment failure. The results suggest HFNC is safe to use in acute hospital settings.
Weight management and determinants of weight change in patients with coronary artery disease
Authors: Tijssen Arno , Snaterse Marjolein , Minneboo Madelon , Lachman Sangeeta , Scholte op Reimer Wilma , Peters Ron J , Jørstad Harald Thune 
Published: July 2021

ObjectiveTo study the effects of a comprehensive secondary prevention programme on weight loss and to identify determinants of weight change in patients with coronary artery disease (CAD).MethodsWe performed a secondary analysis focusing on the subgroup of overweight CAD patients (BMI ≥27 kg/m2) in the Randomised Evaluation of Secondary Prevention by Outpatient Nurse SpEcialists-2 (RESPONSE-2) multicentre randomised trial. We evaluated weight change from baseline to 12-month follow-up; multivariable logistic regression with backward elimination was used to identify determinants of weight change.ResultsIntervention patients (n=280) lost significantly more weight than control patients (n=257) (−2.4±7.1 kg vs −0.2±4.6 kg; p<0.001). Individual weight change varied widely, with weight gain (≥1.0 kg) occurring in 36% of interventions versus 41% controls (p=0.21). In the intervention group, weight loss of ≥5% was associated with higher age (OR 2.94), lower educational level (OR 1.91), non-smoking status (OR 2.92), motivation to start with weight loss directly after the baseline visit (OR 2.31) and weight loss programme participation (OR 3.33), whereas weight gain (≥1 kg) was associated with smoking cessation ≤6 months before or during hospitalisation (OR 3.21), non-Caucasian ethnicity (OR 2.77), smoking at baseline (OR 2.70), lower age (<65 years) (OR 1.47) and weight loss programme participation (OR 0.59).ConclusionThe comprehensive secondary prevention programme was, on average, effective in achieving weight loss. However, wide variation was observed. As weight gain was observed in over one in three participants in both groups, prevention of weight gain may be as important as attempts to lose weight.Trial registration numberNTR3937.
Type 2 diabetes mellitus and antibiotic-resistant infections: a systematic review and meta-analysis
Authors: Carrillo-Larco Rodrigo M , Anza-Ramírez Cecilia , Saal-Zapata Giancarlo , Villarreal-Zegarra David , Zafra-Tanaka Jessica Hanae , Ugarte-Gil Cesar , Bernabé-Ortiz Antonio 
Published: July 2021

BackgroundType 2 diabetes mellitus (T2DM) has been associated with infectious diseases; however, whether T2DM is associated with bacterial-resistant infections has not been thoroughly studied. We ascertained whether people with T2DM were more likely to experience resistant infections in comparison to T2DM-free individuals.MethodsSystematic review and random-effects meta-analysis. The search was conducted in Medline, Embase and Global Health. We selected observational studies in which the outcome was resistant infections (any site), and the exposure was T2DM. We studied adult subjects who could have been selected from population-based or hospital-based studies. I2was the metric of heterogeneity. We used the Newcastle-Ottawa risk of bias scale.ResultsThe search retrieved 3370 reports, 97 were studied in detail and 61 (449 247 subjects) were selected. Studies were mostly cross-sectional or case–control; several infection sites were studied, but mostly urinary tract and respiratory infections. The random-effects meta-analysis revealed that people with T2DM were twofold more likely to have urinary tract (OR=2.42; 95% CI 1.83 to 3.20; I219.1%) or respiratory (OR=2.35; 95% CI 1.49 to 3.69; I258.1%) resistant infections. Although evidence for other infection sites was heterogeneous, they consistently suggested that T2DM was associated with resistant infections.ConclusionsCompelling evidence suggests that people with T2DM are more likely to experience antibiotic-resistant urinary tract and respiratory infections. The evidence for other infection sites was less conclusive but pointed to the same overall conclusion. These results could guide empirical treatment for patients with T2DM and infections.
Src/lck inhibitor dasatinib reversibly switches off cytokine release and T cell cytotoxicity following stimulation with T cell bispecific antibodies
Authors: Leclercq Gabrielle , Haegel Hélène , Schneider Anneliese , Giusti Anna Maria , Marrer-Berger Estelle , Boetsch Christophe , Walz Antje-Christine , Pulko Vesna , Sam Johannes , Challier John , Ferlini Cristiano , Odermatt Alex , Umaña Pablo , Bacac Marina , Klein Christian 
Published: July 2021

BackgroundT cell engagers are bispecific antibodies recognizing, with one moiety, the CD3ε chain of the T cell receptor and, with the other moiety, specific tumor surface antigens. Crosslinking of CD3 upon simultaneous binding to tumor antigens triggers T cell activation, proliferation and cytokine release, leading to tumor cell killing. Treatment with T cell engagers can be associated with safety liabilities due to on-target on-tumor, on-target off-tumor cytotoxic activity and cytokine release syndrome (CRS). Tyrosine kinases such as SRC, LCK or ZAP70 are involved in downstream signaling pathways after engagement of the T cell receptor and blocking these kinases might serve to abrogate T cell activation when required (online supplemental material 1). Dasatinib was previously identified as a potent kinase inhibitor that switches off CAR T cell functionality.MethodsUsing an in vitro model of target cell killing by human peripheral blood mononuclear cells, we assessed the effects of dasatinib combined with 2+1 T cell bispecific antibodies (TCBs) including CEA-TCB, CD19-TCB or HLA-A2 WT1-TCB on T cell activation, proliferation and target cell killing measured by flow cytometry and cytokine release measured by Luminex. To determine the effective dose of dasatinib, the Incucyte system was used to monitor the kinetics of TCB-mediated target cell killing in the presence of escalating concentrations of dasatinib. Last, the effects of dasatinib were evaluated in vivo in humanized NSG mice co-treated with CD19-TCB. The count of CD20+ blood B cells was used as a readout of efficacy of TCB-mediated killing and cytokine levels were measured in the serum.ResultsDasatinib concentrations above 50 nM prevented cytokine release and switched off-target cell killing, which were subsequently restored on removal of dasatinib. In addition, dasatinib prevented CD19-TCB-mediated B cell depletion in humanized NSG mice. These data confirm that dasatinib can act as a rapid and reversible on/off switch for activated T cells at pharmacologically relevant doses as they are applied in patients according to the label.ConclusionTaken together, we provide evidence for the use of dasatinib as a pharmacological on/off switch to mitigate off-tumor toxicities or CRS by T cell bispecific antibodies.