bluuebunny/crossref_metadata_2025_split huggingface dataset:
Large Eddy Simulations on Fan Shaped Film Cooling Hole With Upstream Boundary Layer Turbulence Effect Generated by Trip Strip
Authors: Kang Young Seok , Jun Sangook , Rhee Dong-Ho 
Published: June 2021

Abstract
Large eddy simulations (LESs) on the well-known 7-7-7 fan shaped cooling hole were carried out. Like using a trip strip to create turbulent boundary layer in practical experiments, trip strips with different configurations were placed upstream of the cooling hole to investigate incoming turbulent boundary layer effect on the film cooling flow behavior. Without the trip, horseshoe vortex generated by laminar boundary layer induced laterally discharging cooling flow in the lateral direction. Meanwhile, the induced cooling flow formed high film cooling effectiveness region around the film cooling hole. When the incoming boundary flow was turbulent, laterally discharged cooling flow was influenced by the turbulent boundary layer to dissipate to the main flow and resultant high effectiveness region disappeared. Depending on the trip configuration, quantitative characteristics of boundary layer such as turbulent intensity, momentum thickness, and shape factor were strongly affected. Some trip configurations resulted in fully developed turbulent boundary layer just before leading edge of the film cooling hole. In such cases, distribution of the film cooling effectiveness showed a reasonable agreement with available experimental data where the quantitative properties of the turbulent boundary layer were similar. However, when the trip was located too close to the film cooling hole, the separated and reattached flow did not develop into the stabilized turbulent boundary layer. Then strong turbulence intensity in the main flow boundary layer stimulated break down of the cooling flow vortex structure and early dissipation to the main flow. It resulted in restricted film cooling flow coverage.
Particulate Emission Reduction by Fuel Injection Timing Optimization in a Gasoline Direct Injection Engine
Authors: Sharma Nikhil , Agarwal Avinash Kumar 
Published: June 2021

Abstract
Optimized fuel injection timings in internal combustion engines exhibit superior performance, combustion characteristics, and lower emissions. Particularly, particulate emissions from a gasoline direct injection (GDI) engines are highly dependent on fuel injection timings. GDI engines have emerged as a popular choice of power plants for automobiles among customers worldwide. They are preferred over multiple-port fuel injection (MPFI) engines in the transport sector because of their superior fuel economy and performance characteristics. The main objective of this study is to optimize a GDI engine for the lowest particulate emission at different fuel injection timings. GDI engine was investigated for particulate matter (PM) mass/particulate number (PN) emissions at five fuel injection timings (230, 250, 270, 290, and 310 deg bTDC), covering the entire envelope. Once the optimum fuel injection timing was determined, an engine exhaust particle sizer was used to measure the particle size-number distribution. Particulate samples from the engine were also collected on a filter paper for morphological investigations of particulates collected under optimized fuel injection timings. These experiments confirmed the importance and need to optimize the fuel injection timings at every engine operating point to reduce the PM/PN emissions from a GDI engine, which remains one of the biggest unresolved challenges to this technology.
Effect of dexamethasone on complications or all cause mortality after major non-cardiac surgery: multicentre, double blind, randomised controlled trial
Authors: Asehnoune Karim , Le Moal Charlene , Lebuffe Gilles , Le Penndu Marguerite , Josse Nolwen Chatel , Boisson Matthieu , Lescot Thomas , Faucher Marion , Jaber Samir , Godet Thomas , Leone Marc , Motamed Cyrus , David Jean Stephane , Cinotti Raphael , El Amine Younes , Liutkus Darius , Garot Matthias , Marc Antoine , Le Corre Anne , Thomasseau Alexandre , Jobert Alexandra , Flet Laurent , Feuillet Fanny , Pere Morgane , Futier Emmanuel , Roquilly Antoine 
Published: June 2021

Abstract

Objective
To assess the effect of dexamethasone on complications or all cause mortality after major non-cardiac surgery.

Design
Phase III, randomised, double blind, placebo controlled trial.

Setting
34 centres in France, December 2017 to March 2019.

Participants
1222 adults (>50 years) requiring major non-cardiac surgery with an expected duration of more than 90 minutes. The anticipated time frame for recruitment was 24 months.

Interventions
Participants were randomised to receive either dexamethasone (0.2 mg/kg immediately after the surgical procedure, and on day 1) or placebo. Randomisation was stratified on the two prespecified criteria of cancer and thoracic procedure.

Main outcomes measures
The primary outcome was a composite of postoperative complications or all cause mortality within 14 days after surgery, assessed in the modified intention-to-treat population (at least one treatment administered).

Results
Of the 1222 participants who underwent randomisation, 1184 (96.9%) were included in the modified intention-to-treat population. 14 days after surgery, 101 of 595 participants (17.0%) in the dexamethasone group and 117 of 589 (19.9%) in the placebo group had complications or died (adjusted odds ratio 0.81, 95% confidence interval 0.60 to 1.08; P=0.15). In the stratum of participants who underwent non-thoracic surgery (n=1038), the primary outcome occurred in 69 of 520 participants (13.3%) in the dexamethasone group and 93 of 518 (18%) in the placebo group (adjusted odds ratio 0.70, 0.50 to 0.99). Adverse events were reported in 288 of 613 participants (47.0%) in the dexamethasone group and 296 of 609 (48.6%) in the placebo group (P=0.46).

Conclusions
Dexamethasone was not found to significantly reduce the incidence of complications and death in patients 14 days after major non-cardiac surgery. The 95% confidence interval for the main result was, however, wide and suggests the possibility of important clinical effectiveness.

Trial registration

ClinicalTrials.gov
NCT03218553
.
Length of hospital stay in aneurysmal subarachnoid hemorrhage patients without vasospasm on angiography: potential for a fast-track discharge cohort
Authors: Catapano Joshua S , Srinivasan Visish M , Rumalla Kavelin , Labib Mohamed A , Nguyen Candice L , Cole Tyler S , Baranoski Jacob F , Rutledge Caleb , Rahmani Redi , Lawton Michael T , Ducruet Andrew F , Albuquerque Felipe C 
Published: June 2021

BackgroundPatients with aneurysmal subarachnoid hemorrhage (aSAH) frequently suffer from vasospasm. We analyzed the association between absence of early angiographic vasospasm and early discharge.MethodsAll aSAH patients treated from August 1, 2007, to July 31, 2019, at a single tertiary center were reviewed. Patients undergoing diagnostic digital subtraction angiography (DSA) on post-aSAH days 5 to 7 were analyzed; cohorts with and without angiographic vasospasm (angiographic reports by attending neurovascular surgeons) were compared. Primary outcome was hospital length of stay; secondary outcomes were intensive care unit length of stay, 30 day return to the emergency department (ED), and poor neurologic outcome, defined as a modified Rankin Scale (mRS) score >2.ResultsA total of 298 patients underwent DSA on post-aSAH day 5, 6, or 7. Most patients (n=188, 63%) had angiographic vasospasm; 110 patients (37%) did not. Patients without vasospasm had a significantly lower mean length of hospital stay than vasospasm patients (18.0±7.1 days vs 22.4±8.6 days; p<0.001). The two cohorts did not differ significantly in the proportion of patients with mRS scores >2 at last follow-up or those returning to the ED before 30 days. After adjustment for Hunt and Hess scores, Fisher grade, admission Glasgow Coma Scale score, and age, logistic regression analysis showed that the absence of vasospasm on post-aSAH days 5–7 predicted discharge on or before hospital day 14 (OR 3.4, 95% CI 1.8 to 6.4, p<0.001).ConclusionLack of angiographic vasospasm 5 to 7 days after aSAH is associated with shorter hospitalization, with no increase in 30 day ED visits or poor neurologic outcome.
Learning curves for transradial access versus transfemoral access in diagnostic cerebral angiography: a case series
Authors: Tso Michael K , Rajah Gary B , Dossani Rimal H , Meyer Michael J , McPheeters Matthew J , Vakharia Kunal , Waqas Muhammad , Snyder Kenneth V , Levy Elad I , Siddiqui Adnan H , Davies Jason M 
Published: June 2021

BackgroundThe perception of a steep learning curve associated with transradial access has resulted in its limited adoption in neurointervention despite the demonstrated benefits, including decreased access-site complications.ObjectiveTo compare learning curves of transradial versus transfemoral diagnostic cerebral angiograms obtained by five neurovascular fellows as primary operator.MethodsThe first 100–150 consecutive transradial and transfemoral angiographic scans performed by each fellow between July 2017 and March 2020 were identified. Mean fluoroscopy time per artery injected (angiographic efficiency) was calculated as a marker of technical proficiency and compared for every 25 consecutive procedures performed (eg, 1–25, 26–50, 51–75).ResultsWe identified 1242 diagnostic angiograms, 607 transradial and 635 transfemoral. The radial cohort was older (64.3 years vs 62.3 years, p=0.01) and demonstrated better angiographic efficiency (3.4 min/vessel vs 3.7 min/vessel, p=0.03). For three fellows without previous endovascular experience, proficiency was obtained between 25 and 50 transfemoral angiograms. One fellow achieved proficiency after performing 25–50 transradial angiograms; and the two other fellows, in <25 transradial angiograms. The two fellows with previous experience had flattened learning curves for both access types. Two patients experienced transient neurologic symptoms postprocedure. Transradial angiograms were associated with significantly fewer access-site complications (3/607, 0.5% vs 22/635, 3.5%, p<0.01). Radial-to-femoral conversion occurred in 1.2% (7/607); femoral-to-radial conversion occurred in 0.3% (2/635). Over time, the proportion of transradial angiographic procedures increased.ConclusionTechnical proficiency improved significantly over time for both access types, typically requiring between 25 and 50 diagnostic angiograms to achieve asymptomatic improvement in efficiency. Reduced access-site complications and decreased fluoroscopy time were benefits associated with transradial angiography.
Imprints of dark matter on black hole shadows using spherical accretions
Authors: Saurabh K. , Jusufi Kimet 
Published: June 2021

AbstractWe study the possibility of identifying dark matter in the galactic center from the physical properties of the electromagnetic radiation emitted from an optically-thin disk region around a static and spherically symmetric black hole. In particular, we consider two specific models for the optical-thin disk region: a gas at rest and a gas in a radial free fall. Due to the effect of dark matter on the spacetime geometry, we find that the dark matter can increase or decrease the intensity of the electromagnetic flux radiation depending on the dark matter model. To this end, we analyze two simple dark matter models having different mass functions $${\mathcal {M}}(r)$$

M
(
r
)

, with a matter mass M, thickness $$\Delta r_s$$

Δ

r
s

along with a dark matter core radius surrounding the black hole. In addition to that, we explore the scenario of a perfect fluid dark matter surrounding the black hole. We show that in order to have significant effect of dark matter on the intensity of the electromagnetic flux radiation, a high energy density of dark matter near the black hole is needed. We also find that the surrounding dark matter distribution plays a key role on the shadow radius and the intensity of the electromagnetic flux radiation, respectively. Finally we have used the relation between the shadow radius and the quasinormal modes (QNMs) to compute the real part of QNM frequencies.
Evaluation of home detection algorithms on mobile phone data using individual-level ground truth
Authors: Pappalardo Luca , Ferres Leo , Sacasa Manuel , Cattuto Ciro , Bravo Loreto 
Published: June 2021

AbstractInferring mobile phone users’ home location, i.e., assigning a location in space to a user based on data generated by the mobile phone network, is a central task in leveraging mobile phone data to study social and urban phenomena. Despite its widespread use, home detection relies on assumptions that are difficult to check without ground truth, i.e., where the individual who owns the device resides. In this paper, we present a dataset that comprises the mobile phone activity of sixty-five participants for whom the geographical coordinates of their residence location are known. The mobile phone activity refers to Call Detail Records (CDRs), eXtended Detail Records (XDRs), and Control Plane Records (CPRs), which vary in their temporal granularity and differ in the data generation mechanism. We provide an unprecedented evaluation of the accuracy of home detection algorithms and quantify the amount of data needed for each stream to carry out successful home detection for each stream. Our work is useful for researchers and practitioners to minimize data requests and maximize the accuracy of the home antenna location.
Light- and magnetically actuated FePt microswimmers
Authors: Kadiri Vincent Mauricio , Günther Jan-Philipp , Kottapalli Sai Nikhilesh , Goyal Rahul , Peter Florian , Alarcón-Correa Mariana , Son Kwanghyo , Barad Hannah-Noa , Börsch Michael , Fischer Peer 
Published: June 2021

AbstractExternally controlled microswimmers offer prospects for transport in biological research and medical applications. This requires biocompatibility of the swimmers and the possibility to tailor their propulsion mechanisms to the respective low Reynolds number environment. Here, we incorporate low amounts of the biocompatible alloy of iron and platinum (FePt) in its $$\hbox {L1}_{{0}}$$

L1
0

phase in microstructures by a versatile one-step physical vapor deposition process. We show that the hard magnetic properties of $$\hbox {L1}_{{0}}$$

L1
0

FePt are beneficial for the propulsion of helical micropropellers with rotating magnetic fields. Finally, we find that the FePt coatings are catalytically active and also make for Janus microswimmers that can be light-actuated and magnetically guided.
Revisiting the evaluation of central versus peripheral thermoregulatory control in humans
Authors: Ravanelli Nicholas , Gendron Philippe , Gagnon Daniel 
Published: June 2021

Human thermoregulatory control is often evaluated through the relationship between thermoeffector output and core or mean body temperature. In addition to providing a general indication of whether a variable of interest alters thermoregulatory control, this relationship is often used to determine how this alteration may occur. This latter interpretation relies upon two parameters of the thermoeffector output-body temperature relationship: the onset threshold and thermosensitivity. Traditionally, changes in the onset threshold and thermosensitivity are interpreted as “central” or “peripheral” modulation of thermoregulatory control, respectively. This mini-review revisits the origins of the thermoeffector output-body temperature relationship and its use to interpret “central” or “peripheral” modulation of thermoregulatory control. Against this background, we discuss the strengths and weaknesses of this approach and highlight that “central” thermoregulatory control reflects the neural control of body temperature whereas “peripheral” thermoregulatory control reflects properties specific to the thermoeffector organs. We highlight studies that employed more direct approaches to investigate the neural control of body temperature and peripheral properties of thermoeffector organs. We conclude by encouraging future investigations interested in studying thermoregulatory control to more directly investigate the component of the thermoeffector loop under investigation. heat; human; skin blood flow; sweat; thermoregulatory
To Go or Not to Go?—Targeting Tregs Traveling in Tumors
Authors: Chakraborty Sanjukta , Zappasodi Roberta 
Published: June 2021

Abstract
Regulatory T cells (Treg) are one of the major impediments to effective antitumor immunity and successful immunotherapy. Elevated intratumoral Treg frequencies, observed in a variety of malignancies, have been associated with poor prognosis. In this issue of Cancer Research, two studies underscore the potential of harnessing the unique migratory profile of tumor-infiltrating Tregs to selectively eliminate these cells without compromising peripheral tolerance. Both studies identify surface migratory receptors, CCR8 by Campbell and colleagues and GPR15 by Adamczyk and colleagues, as selective markers of intratumoral Tregs in tumor-bearing mice and patients with cancer. Genetic deletion of GPR15 or antibody-mediated depletion of CCR8 was found to preferentially decrease tumor-infiltrating Tregs and substantially delayed tumor progression. Together, these two studies highlight the significance of migratory molecules in intratumoral Tregs and propose two potential selective targets for preferential elimination of tumor-associated “pathogenic” Tregs, which can be hijacked to enhance the response to immunotherapy.
See related articles by Adamczyk et al., p. 2970 and Campbell et al., p. 2983
Cytokine Levels at Birth in Children Who Developed Acute Lymphoblastic Leukemia
Authors: Whitehead Todd P. , Wiemels Joseph L. , Zhou Mi , Kang Alice Y. , McCoy Lucie S. , Wang Rong , Fitch Briana , Petrick Lauren M. , Yano Yukiko , Imani Partow , Rappaport Stephen M. , Dahl Gary V. , Kogan Scott C. , Ma Xiaomei , Metayer Catherine 
Published: June 2021

Abstract

Background:
Prenatal immune development may play an important role in the etiology of childhood acute lymphoblastic leukemia (ALL).

Methods:
Seven cytokines, IL1β, IL4, IL6, IL8, GM-CSF, TNFα, and VEGF, were analyzed in blood spots collected at birth from 1,020 ALL cases and 1,003 controls participating in the California Childhood Leukemia Study. ORs and 95% confidence intervals (95% CI) associated with an interquartile range increment in cytokine levels were calculated using logistic regression, adjusting for sociodemographic and birth characteristics.

Results:
We found that patients with ALL were born with higher levels of a group of correlated cytokines than controls [IL1β: OR of 1.18 (95% confidence interval [CI], 1.03–1.35); IL8: 1.19 (1.03–1.38); TNFα: 1.15 (1.01–1.30); VEGF: 1.16 (1.01–1.33)], especially among children of Latina mothers (ORs from 1.31 to 1.40) and for ALL with high hyperdiploidy (ORs as high as 1.27). We found that neonatal cytokine levels were correlated with neonatal levels of endogenous metabolites which had been previously associated with ALL risk; however, there was no evidence that the cytokines were mediating the relationship between these metabolites and ALL risk.

Conclusions:
We posit that children born with altered cytokine levels are set on a trajectory towards an increased risk for subsequent aberrant immune reactions that can initiate ALL.

Impact:
This is the first study to evaluate the interplay between levels of immunomodulatory cytokines at birth, prenatal exposures, and the risk of childhood ALL.
A Hopeful Leap Forward by Multicentric Cooperation for Precision-Based Therapy for Very Resistant, Relapsed, or Refractory Childhood Leukemia
Authors: Bornhauser Beat C. , Bourquin Jean-Pierre 
Published: June 2021

Abstract

Summary:
Pikman and colleagues report the results of a multicentric prospective clinical trial of the leukemia precision-based therapy (LEAP) consortium that combines identification of targetable lesions in drug-resistant childhood leukemia, tiered based on evidence for genomic lesions and drug target, validation of matching small-molecule targeted agents, and treatment of individual patients. The study demonstrates the impact of genomic information on disease classification, treatment guidance, and translational research, but also illustrates the challenges for target prediction and trial design for increasingly heterogeneous and smaller subgroups of patients.
See related article by Pikman et al., p. 1424.
Extent of Coronary Artery Disease in Patients With Stenotic Bicuspid Versus Tricuspid Aortic Valves
Authors: Dolmaci Onur B. , Legué Juno , Lindeman Jan H. N. , Driessen Antoine H. G. , Klautz Robert J. M. , Van Brakel Thomas J. , Siebelink Hans‐Marc J. , Mertens Bart J. A. , Poelmann Robert E. , Gittenberger‐de Groot Adriana C. , Grewal Nimrat 
Published: June 2021

Background
Bicuspid aortic valve (BAV) is the most common congenital cardiac malformation, which is often complicated by aortic valve stenosis (AoS). In tricuspid aortic valve (TAV), AoS strongly associates with coronary artery disease (CAD) with common pathophysiological factors. Yet, it remains unclear whether AoS in patients with BAV is also associated with CAD. This study investigated the association between the aortic valve morphological features and the extent of CAD.

Methods and Results

A single‐center study was performed, including all patients who underwent an aortic valve replacement attributable to AoS between 2006 and 2019. Coronary sclerosis was graded on preoperative coronary angiographies using the coronary artery greater even than scoring method, which divides the coronaries in 28 segments and scores nonobstructive (20%–49% sclerosis) and obstructive coronary sclerosis (>49% sclerosis) in each segment. Multivariate analyses were performed, controlling for age, sex, and CAD risk factors. A total of 1296 patients (931 TAV and 365 BAV) were included, resulting in 548 matched patients. Patients with TAV exhibited more CAD risk factors (odds ratio [OR], 2.66; 95% CI, 1.79–3.96;
P
<0.001). Patients with BAV had lower coronary artery greater even than 20 (1.61±2.35 versus 3.60±2.79) and coronary artery greater even than 50 (1.24±2.43 versus 3.37±3.49) scores (
P
<0.001), even after correcting for CAD risk factors (
P
<0.001). Patients with TAV more often needed concomitant coronary revascularization (OR, 3.50; 95% CI, 2.42–5.06;
P
<0.001).

Conclusions
Patients with BAV who are undergoing surgery for AoS carry a lower cardiovascular risk profile, correlating with less coronary sclerosis and a lower incidence of concomitant coronary revascularization compared with patients with TAV.
Magnetic Interference on Cardiac Implantable Electronic Devices From Apple iPhone MagSafe Technology
Authors: Nadeem Fahd , Nunez Garcia Arismendy , Thach Tran Cao , Wu Michael 
Published: June 2021

Background
Magnet wireless charging is being utilized increasingly in current generation smartphones. Apple's MagSafe is a proprietary wireless charging technology with an array of magnets that has the capacity to generate magnet fieldstrength >50 gauss (G). We hypothesize that there is clinically significant magnet interference caused by Apple's MagSafe technology on cardiac implantable electronic devices (CIED).

Methods and Results
This study has an in vivo and an ex vivo component. The in vivo component consists of consecutive patients who presented to the electrophysiology laboratory with previously implanted CIEDs. The iPhone 12 Pro Max was directly placed on the skin over the pocket of these patients and the effect was studied by device interrogation. For the ex vivo component of the study, CIEDs from major device companies were tested for magnetic interference caused by iPhone 12 Pro Max through unopened packages. We found that iPhone 12 Pro Max resulted in clinically identifiable magnet interference in 3/3 (100%) participants in vivo and in 8/11 (72.7%) devices ex vivo.

Conclusions
Apple's iPhone 12 Pro Max MagSafe technology can cause magnet interference on CIEDs and has the potential to inhibit lifesaving therapy.