bluuebunny/crossref_metadata_2025 huggingface dataset:
Power flow in the air gap of linear electrical machines by utilisation of the Poynting vector: Part 2 ‐ simulations
Authors: Frost Anna E. , Sjölund Jonathan , Eriksson Sandra , Leijon Mats
Published: July 2022

Different types of linear generators are simulated and their power flow in the air gap is investigated. The results are compared to the analytical expressions derived in Part 1. The simulations and the analytical expressions in Part 1 show the same general behaviour, but the magnitudes are lower for the analytical expressions. One explanation for the difference in magnitude can be that the harmonics of the electric and magnetic fields contribute to the power flow, which is not accounted for in the analytical expressions. Due to results from Part 1, it is investigated if changing the number of poles can decrease the tangential power flow while the normal power flow stays the same. As was suspected, changing the number of poles affected several other factors, which lead to an increase in the normal power flow when increasing the number of poles, even though the electrical power was the same. The tangential power flow also decreased for three out of four generators. Thereby, increasing the number of poles while keeping the same length of the machine, at the cost of reduced pole‐pitch, should be done with precaution.
Shapes of galaxies hosting radio-loud AGNs with z ≤ 1
Authors: Zheng X. C. , Röttgering H. J. A. , van der Wel A. , Duncan K.
Published: July 2022

Links between the properties of radio-loud active galactic nuclei (RLAGNs) and the morphology of their hosts may provide important clues for our understanding of how RLAGNs are triggered. In this work, focusing on passive galaxies, we study the shape of the hosts of RLAGNs selected from the Karl G. Jansky Very Large Array Cosmic Evolution Survey (VLA-COSMOS) 3GHz Large Project, and compare them with previous results based on the first data release (DR1) of the LOFAR Two-Metre Sky Survey (LoTSS). We find that, at redshifts of between 0.6 and 1, high-luminosity (L1.4 GHz ≳ 1024 W Hz−1) RLAGNs have a wider range of optical projected axis ratios than their low-redshift counterparts, which are essentially all found in round galaxies with axis ratios of higher than 0.7. We construct control samples and show that although the hosts of high-redshift RLAGNs with the highest luminosities still have a rounder shape compared with the non-RLAGNs, they on average have a smaller axis ratio (more elongated) than the local RLAGNs with similar stellar masses and radio luminosities. This evolution can be interpreted as a byproduct of radio luminosity evolution, namely that galaxies at fixed stellar mass are more radio luminous at high redshifts: artificially increasing the radio luminosities of local galaxies (z ≤ 0.3) by a factor of 2–4 can remove the observed evolution of the axis ratio distribution. If this interpretation is correct then the implication is that the link between AGN radio luminosity and host galaxy shape is similar at z ≃ 1 to in the present-day Universe.
The diurnal Yarkovsky effect of irregularly shaped asteroids
Authors: Xu Yang-Bo , Zhou Li-Yong , Hui Hejiu , Li Jian-Yang
Published: July 2022

The Yarkovsky effect plays an important role in the motions of small celestial bodies. Increasingly detailed observations bring the need for high-accuracy modelling of the effect. We used the multiphysics software COMSOL to model the diurnal Yarkovsky effect in three dimensions and compare the results with those derived from the widely adopted theoretical linear model. We find that the linear model shows high accuracy for spherical asteroids in most cases. We explored the range of parameters for which the relative error of the linear model is over 10%. For biaxial ellipsoidal asteroids (particularly oblate ones), the linear model systematically overestimates the transverse Yarkovsky force by ~10%. The diurnal effect on triaxial ellipsoids is periodic, and no linear model is available for this phenomenon. Our numerical calculations show that the average effects on triaxial ellipsoids are stronger than those on biaxial ellipsoids. We also investigated the diurnal effect on asteroids of real shapes and find it be overestimated by the linear model by 16% on average, with a maximum of up to 35%. To estimate the strength of the Yarkovsky effect directly from the shape, we introduced the quantity of ‘effective area’ for asteroids of any shape, and find a significant linear relationship between the Yarkovsky migration rate and the effective area. This brings great convenience to the estimation in practice.
Successive phases of serpentinization and carbonation recorded in the Sivas ophiolite (Turkey), from oceanic crust accretion to post-obduction alteration
Authors: Lévy Dan , Callot Jean-Paul , Moretti Isabelle , Duttine Mathieu , Dubreuil Brigitte , de Parseval Philippe , Boudouma Omar
Published: July 2022

The ophiolite of Sivas (Turkey) was studied in order to define the chronology of different alteration events related to a series of serpentinization and carbonation episodes. Six samples were investigated, representative of different types of ophicalcite (partially carbonated serpentinite). X-ray diffraction (XRD) and Mössbauer spectroscopy were used to determine the bulk mineralogy and the bulk Fe3+/Fetot ratio, respectively. Electron microprobe and secondary ion mass spectrometer (SIMS) analyses were also conducted to identify the chemical composition of different mineral phases in addition to the carbon and oxygen isotopic compositions of calcite. An initial, i.e. pre-obduction, phase of olivine and pyroxene serpentinization was followed by a brecciation event associated with precipitation of massive serpentine. This first alteration event occurred during exhumation of the peridotites to the seafloor, followed by a carbonation event at temperatures in the range 35‒100 °C. A low-temperature (∼35 °C) carbonation event occurred between 90 and 65 Ma. Finally, a reheating of the system likely occurred after the obduction at 55‒40 Ma, resulting in a carbonation episode followed by late serpentinization. Our study presents the first direct evidence of serpentinization after obduction. In that geological context, the hydrogen produced during the proposed multiphase serpentinization may have been trapped by the salt deposits overlying the ophiolite but subsurface data will be necessary to define potential traps and reservoirs; further studies are also needed to determine whether the serpentinization process is still ongoing.
Histologisch diagnostizierte okuläre und periokuläre Tuberkulose von 1945 bis 2020
Authors: Küchlin Sebastian , Glegola Mateusz , Schulz Tabea , Auw-Hädrich Claudia
Published: July 2022

Hintergrund Okuläre Tuberkulose ist eine seltene, jedoch wichtige Differenzialdiagnose bei Entzündungen jeglicher Augenstrukturen inkl. der Augenoberfläche und der okulären Adnexe.
Die Diagnostik der Gewebe kann durch deren Unzugänglichkeit zur Biopsie, oftmals unspezifischen Veränderungen und den insensitiven Erregernachweis erschwert sein. Wir interessierten uns
dafür, wie viele tuberkuloseassoziierte Fälle im Archiv des Schwerpunkts Ophthalmopathologie seit 1945 diagnostiziert wurden.

Material und Methoden Wir führten eine retrospektive Analyse historischer Befunde und Präparate des Schwerpunktes Ophthalmopathologie der Klinik für Augenheilkunde in Freiburg durch.
Verfügbare Schnitte befundeten wir hinsichtlich Granulomen, Nekrosen, Riesenzellen, säurefester Stäbchen sowie chronischer und akuter Entzündung systematisch neu und verglichen den aktuellen
und historischen Befund. Weiterhin beschreiben wir einen aktuellen Fall eines Patienten mit Iristuberkulose.

Ergebnisse Unter 50 418 seit 1945 befundeten histopathologischen Fällen fanden wir 23 Befunde von 22 Patienten mit Diagnose einer okulären oder periokulären Tuberkulose. Hiervon
waren 22 Präparate (96%) archiviert und zur Neubefundung verfügbar. Vier Präparate (17%) stammten von Kindern. Die am häufigsten entnommenen Gewebe waren enukleierte Bulbi (10/23, 44%),
gefolgt von Tränensack- (5/23, 22%) und Bindehautpräparaten (2/23, 9%). Die häufigsten histopathologischen Befunde waren Granulome (23/23, 100%), eine chronische Entzündung (22/23, 96%),
Riesenzellen (21/23, 91%) und Nekrose (14/23, 61%). Eine akute entzündliche Reaktion fand sich in 4/23 Präparaten (17%). Der Nachweis säurefester Stäbchen war aus 5 Präparaten angestrebt
worden und hiervon in 3 Fällen gelungen (60%). Die größte Diskrepanz zwischen historischer und retrospektiver Beurteilung zeigte sich im Vorhandensein von Nekrosen (Übereinstimmung in 13/22
Fällen, 59%). Die übrigen Befunde wurden mit hoher Übereinstimmung erhoben (78 – 96%). In einem aktuellen Fall mit Iristumor führte die histopathologische Aufarbeitung zeitgleich mit einem
Leistenpunktat zur Tuberkulosediagnose bei zuvor tumorös interpretierter B-Symptomatik.

Schlussfolgerung Die okuläre Tuberkulose ist eine seltene, aber wichtige histopathologische Differenzialdiagnose. Das klassische Merkmal einer nekrotisierenden Entzündung war in den
verfügbaren Präparaten am seltensten und wurde zudem historisch und aktuell verschiedentlich bewertet. Weitere typische Befunde wie Riesenzellen und ein prädominant lymphozytäres Infiltrat
können auch in Fällen mit Erregernachweis fehlen, sodass diese bei entsprechendem Verdacht nicht als obligat angesehen werden sollten.
Orthostatische Intoleranz: eine klinische Betrachtung
Authors: Lührs Anke , Haensch Carl-Albrecht
Published: July 2022

Schwindel und Unwohlsein – zum Teil auch einhergehend mit einem
passageren Bewusstseinsverlust – gehören zu den
häufigsten Vorstellungsgründen sowohl in der Notaufnahme als
auch in neurologischen und internistischen/allgemeinmedizinischen
Praxen. Dieser CME-Artikel soll eine praxisnahe und klinische Herangehensweise
zeigen, um dem Phänomen der orthostatischen Intoleranz in seinen
zahlreichen Facetten auf die Spur zu kommen.
Use of Pulse Oximetry Pulsatility Index Screening for Critical Congenital Heart Disease
Authors: Rasmussen Maynard , Suttner Denise , Poeltler Debra , Katheria Anup C.
Published: July 2022

Objective This study aimed to compare oximetry data (pre- and postductal oxygen saturation [SpO2], pre- and postductal pulsatility index [PI]) in healthy newborns (≥35 weeks' gestational age) to infants who have critical congenital heart disease (CCHD).

Study Design This is a retrospective analysis of data obtained from electronic medical records, recorded as part of routine pulse oximetry screening (POS) for CCHD in infants born between the years 2013 and 2020. Testing was performed at 24 ± 2 hours of life. Data were analyzed to detect differences in pre- and postductal SpO2 and pre- and postductal PI in healthy newborns compared with infants who have CCHD. Newborns were excluded from analysis if they: (1) had a prenatal diagnosis of CCHD in the medical record, (2) had previously been admitted to the neonatal intensive care unit, or (3) had failed POS but were found no CCHD by diagnostic echocardiography.

Results A total of 88,754 healthy newborns had received POS between the years 2013 and 2020. Of the 88,736 newborn records available for analysis,18 newborns were diagnosed with CCHD. Eight were identified by POS before discharge and 10 were diagnosed after discharge. Infants diagnosed with CCHD by POS had lower pre- and postductal SpO2 compared with normal infants. Their postductal PI was significantly lower. Infants who had CCHD that was not identified by POS had similar pre- and postductal SpO2 values, but their postductal PI was lower. Using a postductal PI cutoff of 1.21 had a receiver operating curve of area under the curve 0.77 (95% confidence interval: 0.672, 0.869) with 74% sensitivity and 61% specificity.

Conclusion In our large cohort of infants born in San Diego County, the postductal PI is lower in infants with CCHD. Given that PI is routinely displayed on every pulse oximeter and the high morbidity of missed CCHD, PI should be incorporated into routine CCHD screening.

Key Points
Fetal Echocardiographic Findings to Predict Early Surgical Repair and Neonatal Outcomes in Fetuses with Isolated Coarctation of the Aorta
Authors: Akalın Münip , Demirci Oya , Yücel İlker K. , Erol Nurdan
Published: July 2022

Objective The aim of this study was to investigate fetal echocardiographic findings in predicting the need for surgical repair in fetuses with coarctation of the aorta (CoA) and to evaluate perinatal outcomes.

Study Design In this retrospective study, fetuses diagnosed with CoA in a tertiary center between January 2015 and June 2021 were analyzed. Fetal echocardiographic measurements and quantitative findings, middle cerebral artery (MCA) and umbilical artery (UA) Doppler indices, and perinatal outcomes were recorded.

Results A total of 57 fetuses with CoA were included in the study. In total, 51 (89.5%) pregnancies resulted in live births and 32 (62.8%) of the neonates underwent surgical repair. The left ventricle/right ventricle width ratio and aortic isthmus z-score were significantly lower in fetuses who underwent surgical repair (p = 0.004 0.001, respectively). Retrograde flow in the aortic isthmus (odds ratio [OR]:7.43; 95% confidence interval [CI]: 1.98–27.76), left-to-right foramen ovale shunt (OR: 8.50; 95% CI: 1.68–42.98), and ventricular septal defect (OR: 9.63; 95% CI: 1.90–48.74) were associated with the need for surgical repair. A new scoring system integrating these echocardiographic findings had 89% specificity and 54% sensitivity in predicting surgical repair. Fetal growth restriction rates, preterm birth rates, mean MCA pulsatility index (PI), and mean UA PI were similar in fetuses with and without surgical repair.

Conclusion A scoring system integrating echocardiographic findings in fetuses with CoA may improve the prediction of surgical repair need. There is no evidence of an increased risk of FGR, preterm birth, and brain sparing effect in fetuses with CoA who require surgical repair.

Key Points
Direct percutaneous endoscopic jejunostomy tube placement in patients post Roux-en-Y gastric bypass, a single tertiary care center experience
Authors: Aryan Mahmoud , Colvin Tyler , Mulki Ramzi , Daley Lauren , Patel Parth , Locke John , Ahmed Ali M. , Kyanam Kabir Baig Kondal R. , Mönkemüller Klaus , Peter Shajan
Published: July 2022

Background and study aims Obesity prevalence continues to rise in the United States with Roux-en-Y gastric bypass (RYGB) surgery being one of the most common bariatric procedures. With this trend, more patients with altered upper gastrointestinal (UGI) anatomy have required endoscopic intervention including direct percutaneous endoscopic jejunostomy (DPEJ) placement. We aimed to assess the safety and success rates of DPEJ in RYGB patients.

Patients and methods All patients at a tertiary care referral center who underwent DPEJ during an 8-year period were queried from a prospectively maintained registry of all enteroscopy procedures. Duplicate cases and altered upper UGI anatomy subtypes other than RYGB were excluded. The final cohort consisted of two groups: RYGB vs native anatomy (NA). Demographic, procedural, readmission, follow-up, and complication data were recorded. Comparative analysis was performed.

Results Seventy-two patients were included where 28 had RYGB and 44 had NA. Both groups had similar baseline and pre-procedure data. Procedure success rate was 89 % in RYGB patients and 98 % in NA patients (P = 0.13). There were no intraprocedural complications. Early and late postprocedural complication rates were similar between the groups (both 4 % vs 7 %). Average follow-up times in the RYGB and NA groups were 12.97 ± 9.35 and 13.44 ± 9.21 months, respectively. Although readmission rates at 1 and 6 months were higher in the NA versus the RYGB group (21 % vs 7 % and 25 % vs 15 %), these differences were not significant.

Conclusions DPEJ can be successful and safely placed in RYGB patients with no significant difference in procedure success, complication, or readmission rates when compared to control.
Computed Tomography Predictors of Vascular Injury in Cranioencephalic Trauma Patients
Authors: Velásquez-Vera Miguel , Rivera-García Juan David , Gómez-Martínez Alejandro , Mier-García Juan Felipe , Salcedo-Moreno Juan Camilo , Peralta-Pizza Fernando
Published: July 2022

Objective A frequent challenge for the neurosurgeon when treating a patient with cranioencephalic trauma is to determine whether the patient has a vascular lesion, when to suspect it, and what studies to request. In this context, the objective of the present study was to identify the variables on cranial computed tomography (CT) scans that predict vascular injury in digital subtraction angiography in patients with cranioencephalic trauma.

Methods We conducted a cross-sectional study of patients with cranioencephalic trauma admitted to the Hospital Universitario del Valle between June 2016 and June 2019. Subjects with available simple CT images of the skull and digital subtraction angiography were included.

Results A total of 138 subjects who met the inclusion criteria were identified. The average age was 32 years, 82% were men, and the most frequent mechanism of injury was firearm wound (59%). The variables associated with vascular injury were fracture of the base of the temporal skull and sphenoid fracture.

Conclusion The presence of fractures of the base of the temporal skull and sphenoid fractures is associated with vascular injury in patients with cranioencephalic trauma.
Understanding the Economics of Aphasia: Recent Findings from Speech and Language Research
Authors: Jacobs Molly , Ellis Charles
Published: July 2022

In recent years, stakeholders engaged in the study, treatment, and understanding of aphasia outcomes have emphasized the need for greater transparency regarding the economics of aphasia rehabilitation. Most notably, third-party payers and clinicians have a keen interest in understanding the resources used to treat aphasia, particularly the cost-effectiveness and value of aphasia treatments. In this article, we review the current literature related to the economic burden of aphasia and the cost and cost-effectiveness of aphasia treatments. To date, relatively few scholars have attempted to study the efficiency, scale, and scope related to the economics of aphasia and the cost-effectiveness of aphasia treatment. While studies of the cost-effectiveness of aphasia treatments have shown rehabilitative treatments conform to established quality and cost benchmarks, the continued progress and developments in the treatment of aphasia and measurement of clinical outcomes has left many areas unstudied. We highlight the need for greater emphasis on the cost-effectiveness of aphasia treatments in addition to the traditional focus on the efficacy of treatment outcomes.
Association of ABO Blood Group Antigen and Neurological Tumors
Authors: Patidar Gopal K. , Dhiman Yashaswi , Hazarika Anjali
Published: July 2022

Background Various risk factors for tumors such as smoking, alcohol consumption, diet, and radiation, etc., were already identified. ABO blood group antigens are also present on epithelia, endothelia, and neurons. Recent evidence suggested the role of ABO antigens in the pathogenesis of certain malignancies.

Materials and Methods A retrospective observational study was conducted in a tertiary care neurosurgical center in North India from January 2016 to December 2018. The hospital information system was used to obtain patient information while the blood center information system was used to collect blood group information. Brain tumors were majorly divided into cavernoma, glioma, meningioma, neuroma, pituitary adenoma, schwannoma, and others.

Results We found a total of 1,970 patients with brain tumors admitted during our study period. Most patients had glioma (33.55%), followed by pituitary adenoma (20.05%) and neuroma (2.23%). B blood group individuals had more prevalence of cavernoma, glioma, meningioma, pituitary adenoma, schwannoma, and others followed by O, A, and AB. Only association of O blood group with neuroma tumor was found statistically significant.

Conclusions Our patient population had blood group distribution similar to our general population and no significant association was observed by blood group antigens and brain tumors. Although neuroma was significantly associated with blood group O but the prevalence of neuroma in our patient population is very low hence large sample study is required to draw a firm conclusion regarding this association.
Usability and Acceptability of a Computer-Based Social Communication Intervention for Persons with Traumatic Brain Injury: A Mixed-Methods Study
Authors: Meulenbroek Peter , Cherney Leora R.
Published: July 2022

Computer-based interventions for persons with traumatic brain injury (TBI) are a rapidly developing treatment modality. However, the usability and acceptability of such treatments have not been thoroughly studied. We describe the user-experience of a computerized intervention in persons with TBI called the Work-Related Communication (WoRC) program. Two coders used qualitative analysis of semi-structured interviews to complete a thematic content analysis along with a cost–benefit analysis. Ten participants with severe TBI more than 1-year postinjury were interviewed. Seven participants were male, and three were female. Their mean age was 41.6 years (standard deviation: 13.1). All had 4 years of college or less and experienced severe TBIs. A qualitative analysis of the WoRC program usability resulted in the categories of Content (aspects of treatment approach), Interface (aspects of presentation), and Abilities (aspects of the cognitive disorder). WoRC program acceptability categories emerged as Specific (trained strategies can be applied to specific scenarios) and Personal (individual factors related to willingness to implement the trained strategies). The cost–benefit analysis demonstrated a 50.2% reduction in treatment costs, indicating that computer-enhanced interventions are a potentially cost-effective way to increase behavioral outcomes. We discuss these findings as they relate to future development of computer-enhanced programs for persons with TBI.
Effects of Magnesium Sulfate on Intraoperative Blood Loss and Anesthetic Requirement in Meningioma Patients Undergoing Craniotomy with Tumor Removal: A Prospective Randomized Study
Authors: Jitsinthunun Thanawut , Raksakietisak Manee , Pantubtim Chanitda , Mahatnirunkul Porntip
Published: July 2022

Background Meningioma brain tumor is associated with significant blood loss. Magnesium (Mg), a calcium blocker, can facilitate blood pressure control during surgery. This study aimed to evaluate effects of magnesium on blood loss, anesthetic requirement, and its neuroprotective effect in meningioma patients undergoing craniotomy.

Methods Eighty patients aged between 18 and 70, American Society of Anesthesiologists physical status I and II, diagnosed with meningioma and scheduled for craniotomy tumor removal were randomized into two groups. Group M (Mg) received intravenous magnesium sulfate 40 mg/kg over 30 minutes initiated at skin incision and followed by continuous infusion of 10 mg/kg/h until dura closure. Group N (NSS) received 0.9% NaCl as placebo. Anesthesiologists in charge, surgeons, and patients were all blinded. The assessed outcomes were perioperative blood loss, anesthetic requirement, and pre- and postoperative neurocognitive functions assessed by Montreal Cognitive Assessment (MoCA).

Results Thirty-eight patients in each group were analyzed. In group M, the intraoperative blood losses were 500 (70, 2300) mL, and 510 (100, 1600) mL in group N (p = 0.315). Patients who received blood within 24 hours were 39.5% in group M and 47.4% in group N (p = 0.644). No differences were observed in anesthetic requirement, intraoperative mean arterial pressure, hypotensive episodes, and vasopressor usages. There were no significant differences in postoperative MoCA score. Magnesium levels did not exceed acceptable levels.

Conclusions Magnesium administration in meningioma patients had no significant effects on blood loss, anesthetic requirement, and postoperative cognitive function.
The Politics of Who Gets What and Why: Learning from the Targeting of Social Cash Transfers in Zambia
Authors: Pruce Kate
Published: July 2022

Targeting remains a highly contentious aspect of social protection design, despite the growing body of evidence on various targeting mechanisms. While targeting is often framed as identifying the poorest households within limited budgets, such decisions are inherently political and shaped by notions of social justice. This in-depth study of a contested cash transfer model in Zambia finds that local ideas of deservingness led to the rejection of eligible fit-for-work recipients, and changes to the targeting model to prioritise incapacitated households. The analysis draws on interviews with government and policy actors, as well as focus group discussions in communities receiving cash transfers. Applying van Oorschot’s deservingness heuristic to this data reveals that the criterion of control (of circumstance) was prioritised by local level respondents. The paper argues that popular perceptions of deservingness—and the broader social justice implications—need to be taken seriously in the design and analysis of targeting.
PIC simulations of a frequency agile multicavity relativistic magnetron using irregular ring metamaterials driven by a transparent cathode
Authors: Li Y. , Liu M. , Feng J. , Wang C. , Schamiloglu E. , Liu C. , Jiang W. , Li F. , Han J.
Published: July 2022

The design of an agile 5° irregular ring metamaterial for a 24-cavity relativistic magnetron with diffraction output (MDO) using single-stepped cavities for frequency switching is presented. By inserting six pieces of 5° irregular ring metamaterials in place of the traditional 5° vanes of a slow wave structure, the operating frequency can be tuned. When U = 400 kV high voltage is applied, with an applied magnetic field B = 0.36 T, the operating mode can be switched from the TE41 mode with a frequency of 2.585 GHz to the TE31 mode with a frequency of 2.282 GHz. The 24-cavity anode block is an electromagnetic medium which can support the operating mode working under its cutoff frequency, and the insertion of the irregular ring metamaterials alters its dispersion relation. The results suggest a new technique to achieve frequency agility by changing the dispersion relation of the electromagnetic system using a metamaterial unit cell. This work seeks to design a compact high power microwave source for a narrowband directed microwave wave beam that is suitable for frequency agility.
Magnetic tunnel junctions using epitaxially grown FeAlSi electrode with soft magnetic property
Authors: Akamatsu Shoma , Oogane Mikihiko , Tsunoda Masakiyo , Ando Yasuo
Published: July 2022

Magnetic tunnel junctions (MTJs) with (001)-oriented D03-FeAlSi epitaxial films, which have both soft magnetic properties and surface flatness, were fabricated and characterized. A tunnel magnetoresistance (TMR) ratio of 121% was observed, and a relatively low switching field was also confirmed, reflecting the soft magnetic property of FeAlSi. However, the results of the cross-sectional TEM image of the MTJ and the bias dependence of the TMR ratio indicate that the FeAlSi/MgO interface is probably oxidized. Therefore, since an insertion layer at the interface can suppress oxidation and further improve the TMR ratio, MTJs using FeAlSi epitaxial films are promising structures suitable for applications such as MTJ-based magnetic sensors and worthy of further investigation.
Challenges in predicting ΔrxnG in solution: The chelate effect
Authors: Mukadam A. A. , East A. L. L.
Published: July 2022

Gibbs energies for reactions involving aqueous ions are challenging to predict due to the large solvation energies of such ions. A stringent test would be the ab initio reproduction of the aqueous-phase chelate effect, an entropic effect in reactions of very small enthalpy changes. This paper examines what is required to achieve such a reproduction for the paradigmatic reaction M(NH3)42+ + 2 en → M(en)22+ + 4 NH3 (en = 1,2-ethylenediamine), for which ΔrxnG* and ΔrxnH* are −2.3 and +1.6 kcal mol−1, respectively, if M = Zn. Explicit solvation via simulation was avoided in order to allow sufficiently accurate electronic structure models; this required the use of continuum solvation models (CSMs), and a great deal of effort was made in attempting to lower the relative errors of ΔsolvG*[M(NH3)42+] vs ΔsolvG*[M(en)22+] from the CSMs available in Gaussian software. CSMs in ADF and JDFTx software were also tested. A uniform 2.2 kcal mol−1 accuracy in ΔrxnG* for all three metal-atom choices M = {Zn, Cd, Hg} was eventually achieved, but not from any of the known CSMs tested, nor from cavity size reoptimization, nor from semicontinuum modeling: post facto solvation energy corrections [one per solute type, NH3, en, M(NH3)42+, M(en)22+] were needed. It is hoped that this study will aid (and encourage) further CSM development for coordination-complex ions.
Viscous interference torque analysis of liquid floated gyroscope based on multi-source data learning
Authors: Zhang Yaping , Wang Yanzhong , Zhang Fuli , Niu Wentao , Song Guanhua , Lu Boji
Published: July 2022

The liquid floated gyroscope (LFG) is a core instrument of the inertial navigation system, which is used to obtain the angular motion information of the carrier. Under the thermal effect of electronic components, the floating oil inside the instrument flows slowly, thereby introducing a viscous interference torque (VIT) acting on the floater surface, which will affect the output accuracy of the instrument. Since the magnitude of VIT is extremely small, there is currently no effective means to obtain its accurate value. Therefore, this work aims to combine the advantages of experiment and simulation and then proposes a feasible method to predict the VIT. First, a gas–liquid–solid three-phase coupled heat transfer model of the LFG was established, and the relative error between the calculated temperature and the test temperature of the calibration point is 3.5%. The computational fluid dynamics method was adopted to calculate the VIT under different oil temperature distributions; the backpropagation neural network algorithm was selected to build a network model between the temperature distribution and the VIT, and the model fitting accuracy was 0.99. Then, the actual temperature distribution of the gyro oil was obtained through experiments, which was taken as an input of the neural network to predict the VIT. The relative error between the predicted and simulation values under the same conditions was 4.18%. The proposed method provides a feasible scheme to predict the microscopic VIT that is difficult to measure, which provides a theoretical reference for the accuracy improvement of LFGs.
The evolution of rock friction is more sensitive to slip than elapsed time, even at near-zero slip rates
Authors: Bhattacharya Pathikrit , Rubin Allan M. , Tullis Terry E. , Beeler Nicholas M. , Okazaki Keishi
Published: July 2022

Nearly all frictional interfaces strengthen as the logarithm of time when sliding at ultra-low speeds. Observations of also logarithmic-in-time growth of interfacial contact area under such conditions have led to constitutive models that assume that this frictional strengthening results from purely time-dependent, and slip-insensitive, contact-area growth. The main laboratory support for such strengthening has traditionally been derived from increases in friction during “load-point hold” experiments, wherein a sliding interface is allowed to gradually self-relax down to subnanometric slip rates. In contrast, following step decreases in the shear loading rate, friction is widely reported to increase over a characteristic slip scale, independent of the magnitude of the slip-rate decrease—a signature of slip-dependent strengthening. To investigate this apparent contradiction, we subjected granite samples to a series of step decreases in shear rate of up to 3.5 orders of magnitude and load-point holds of up to 10,000 s, such that both protocols accessed the phenomenological regime traditionally inferred to demonstrate time-dependent frictional strengthening. When modeling the resultant data, which probe interfacial slip rates ranging from 3 .

μ
m
·

s

−
1

. to less than

10

−
5

μ
m
·

s

−
1

, we found that constitutive models where low slip-rate friction evolution mimics log-time contact-area growth require parameters that differ by orders of magnitude across the different experiments. In contrast, an alternative constitutive model, in which friction evolves only with interfacial slip, fits most of the data well with nearly identical parameters. This leads to the surprising conclusion that frictional strengthening is dominantly slip-dependent, even at subnanometric slip rates.
Inhibitors of eIF4G1–eIF1 uncover its regulatory role of ER/UPR stress-response genes independent of eIF2α-phosphorylation
Authors: Sehrawat Urmila , Haimov Ora , Weiss Benjamin , Tamarkin-Ben Harush Ana , Ashkenazi Shaked , Plotnikov Alexander , Noiman Tzahi , Leshkowitz Dena , Stelzer Gil , Dikstein Rivka
Published: July 2022

During translation initiation, eIF4G1 dynamically interacts with eIF4E and eIF1. While the role of eIF4E–eIF4G1 is well established, the regulatory functions of eIF4G1–eIF1 are poorly understood. Here, we report the identification of the eIF4G1–eIF1 inhibitors i14G1-10 and i14G1-12. i14G1s directly bind eIF4G1 and inhibit translation in vitro and in the cell, and their effects on translation are dependent on eIF4G1 levels. Translatome analyses revealed that i14G1s mimic eIF1 and eIF4G1 perturbations on the stringency of start codon selection and the opposing roles of eIF1–eIF4G1 in scanning-dependent and scanning-independent short 5′ untranslated region (UTR) translation. Remarkably, i14G1s activate ER/unfolded protein response (UPR) stress-response genes via enhanced ribosome loading, elevated 5′UTR translation at near-cognate AUGs, and unexpected concomitant up-regulation of coding-region translation. These effects are, at least in part, independent of eIF2α-phosphorylation. Interestingly, eIF4G1–eIF1 interaction itself is negatively regulated by ER stress and mTOR inhibition. Thus, i14G1s uncover an unknown mechanism of ER/UPR translational stress response and are valuable research tools and potential drugs against diseases exhibiting dysregulated translation.
Geometric trade-off between contractile force and viscous drag determines the actomyosin-based motility of a cell-sized droplet
Authors: Sakamoto Ryota , Izri Ziane , Shimamoto Yuta , Miyazaki Makito , Maeda Yusuke T.
Published: July 2022

Cell migration in confined environments is fundamental for diverse biological processes from cancer invasion to leukocyte trafficking. The cell body is propelled by the contractile force of actomyosin networks transmitted from the cell membrane to the external substrates. However, physical determinants of actomyosin-based migration capacity in confined environments are not fully understood. Here, we develop an in vitro migratory cell model, where cytoplasmic actomyosin networks are encapsulated into droplets surrounded by a lipid monolayer membrane. We find that the droplet can move when the actomyosin networks are bound to the membrane, in which the physical interaction between the contracting actomyosin networks and the membrane generates a propulsive force. The droplet moves faster when it has a larger contact area with the substrates, while narrower confinement reduces the migration speed. By combining experimental observations and active gel theory, we propose a mechanism where the balance between sliding friction force, which is a reaction force of the contractile force, and viscous drag determines the migration speed, providing a physical basis of actomyosin-based motility in confined environments.
EBNA2-EBF1 complexes promote MYC expression and metabolic processes driving S-phase progression of Epstein-Barr virus–infected B cells
Authors: Beer Sophie , Wange Lucas E. , Zhang Xiang , Kuklik-Roos Cornelia , Enard Wolfgang , Hammerschmidt Wolfgang , Scialdone Antonio , Kempkes Bettina
Published: July 2022

Epstein-Barr virus (EBV) is a human tumor virus which preferentially infects resting human B cells. Upon infection in vitro, EBV activates and immortalizes these cells. The viral latent protein EBV nuclear antigen 2 (EBNA2) is essential for B cell activation and immortalization; it targets and binds the cellular and ubiquitously expressed DNA-binding protein CBF1, thereby transactivating a plethora of viral and cellular genes. In addition, EBNA2 uses its N-terminal dimerization (END) domain to bind early B cell factor 1 (EBF1), a pioneer transcription factor specifying the B cell lineage. We found that EBNA2 exploits EBF1 to support key metabolic processes and to foster cell cycle progression of infected B cells in their first cell cycles upon activation. The α1-helix within the END domain was found to promote EBF1 binding. EBV mutants lacking the α1-helix in EBNA2 can infect and activate B cells efficiently, but activated cells fail to complete the early S phase of their initial cell cycle. Expression of
MYC
, target genes of MYC and E2F, as well as multiple metabolic processes linked to cell cycle progression are impaired in EBVΔα1-infected B cells. Our findings indicate that EBF1 controls B cell activation via EBNA2 and, thus, has a critical role in regulating the cell cycle of EBV-infected B cells. This is a function of EBF1 going beyond its well-known contribution to B cell lineage specification.
Genomic and epigenetic landscapes drive CRISPR-based genome editing inBifidobacterium
Authors: Pan Meichen , Morovic Wesley , Hidalgo-Cantabrana Claudio , Roberts Avery , Walden Kimberly K. O. , Goh Yong Jun , Barrangou Rodolphe
Published: July 2022

Bifidobacteriumis a commensal bacterial genus ubiquitous in the human gastrointestinal tract, which is associated with a range of health benefits. The advent of CRISPR-based genome editing technologies provides opportunities to investigate the genetics of important bacteria and transcend the lack of genetic tools in bifidobacteria to study the basis for their health-promoting attributes. Here, we repurpose the endogenous type I-G CRISPR-Cas system and adopt an exogenous CRISPR base editor for genome engineering inB. animalissubsp.lactis,demonstrating that both genomic and epigenetic contexts drive editing outcomes across strains. We reprogrammed the endogenous type I-G system to screen for naturally occurring large deletions up to 27 kb and to generate a 500-bp deletion intetWto abolish tetracycline resistance. A CRISPR-cytosine base editor was optimized to install C•G-to-T•A amber mutations to resensitize multipleB. lactisstrains to tetracycline. Remarkably, we uncovered epigenetic patterns that are distributed unevenly amongB. lactisstrains, despite their genomic homogeneity, that may contribute to editing efficiency variability. Insights were also expanded toBifidobacterium longumsubsp.infantisto emphasize the broad relevance of these findings. This study highlights the need to develop individualized CRISPR-based genome engineering approaches for distinct bacterial strains and opens avenues for engineering of next generation probiotics.
The origin of Weyl gauging in metric-affine theories
Authors: Sauro Dario , Zanusso Omar
Published: July 2022

In the first part, we discuss the interplay between local scale invariance and metric-affine degrees of freedom from few distinct points of view. We argue, rather generally, that the gauging of Weyl symmetry is a natural byproduct of requiring that scale invariance is a symmetry of a gravitational theory that is based on a metric and on an independent affine structure degrees of freedom. In the second part, we compute the Nöther identities associated with all the gauge symmetries, including Weyl, Lorentz and diffeomorphisms invariances, for general actions with matter degrees of freedom, exploiting a gauge covariant generalization of the Lie derivative. We find two equivalent ways to approach the problem, based on how we regard the spin-connection degrees of freedom, either as an independent object or as the sum of two Weyl invariant terms. The latter approach, which rests upon the use of a Weyl-covariant connection with desirable properties, denoted

∇

^

, is particularly convenient and constitutes one of our main results.
An A0 mode Lamb-wave AlN resonator on SOI substrate with vertically arranged double-electrodes
Authors: Cao Haichao , Lu Xianzheng , Ren Hao
Published: July 2022

In this paper, a novel vertically arranged double-electrodes A0 mode Lamb-wave AlN resonator on SOI substrate with a high electromechanical coupling coefficient and high figure of merit (FOM) is reported. The AlN resonator has a sandwich structure with aluminum and N-type doped silicon as electrode layers and a 500 nm thick AlN film as piezoelectric layer. The resonator has only two electrodes vertically arranged rather than horizontal interdigitated (IDT) electrodes which is common in conventional Lamb-wave resonators. The electrode gaps for the vertically arranged double-electrodes resonators are defined by AlN layer thickness rather than by photolithography for lateral field excitation resonators, which results in higher electric field strength and higher electromechanical coupling efficient (

k

t

2

). Compared with conventional thickness field excitation (TFE) resonators with floating bottom electrodes, the vertically arranged double-electrodes resonators have higher electric field strength as the potential difference is larger between the top electrode and bottom electrode than that between the IDT electrodes and floating electrode. As a result, a higher electromechanical coupling coefficient is achieved. Furthermore, the resonant frequency of the vertically arranged double-electrodes resonator presented in this work can be defined by photolithography by controlling the width of the silicon layer. The

k

t

2

of the vertically arranged double-electrodes resonator calculated from the measurement results of admittance versus frequency by numerically fitting with the Butterworth Van Dyke model shows an increase by 3.85 times, from 0.073% to 0.281% compared with conventional TFE resonators, and the FOM also increases by three times, from 2.66 to 7.99. This work provides a new structure to design future AlN Lamb-wave resonators on SOI substrate.
Self-consistent fractal geometry in polyampholyte hydrogels undergoing exchange and correlation charge-density
Authors: Xing Ziyu , Lu Haibao , Fu Yong-Qing
Published: July 2022

Polyampholyte (PA) hydrogels are incorporated of many internally charged polymer chains, which play an important role to influence the fractal networks and dynamic elasticity of the PA hydrogels owing to their different exchange and correlation charge-densities. Many properties of the PA hydrogels, such as mechanical strength and deformation, are significantly dependent on their fractal networks. However, working principles of chemo-mechanical coupling between the fractal networks and the elasticity of PA hydrogels have not been fully understood. In this study, a self-consistent fractal geometry model integrated with a complex function is proposed to understand the constitutive relationship between dynamic networks and tailorable mechanics in the PA hydrogels. The newly developed model is uniquely incorporated with the mechanochemistry, and describes the chemical polarization reactions of charged networks and their mechanical behaviors using complex fractal functions. Based on the rubber elasticity theory, constitutive stress–strain relationships of fractal networks have been described using their elastic, conformational, repulsive and polarization free-energy functions. Finally, effectiveness of the proposed model has been verified using both finite element analysis and experimental results of the PA hydrogels reported in literature.
An effective method to enhance the underwater sound absorption performance by constructing a membrane-type acoustic metamaterial
Authors: Sun Yingjian , Yuan Xujin , Jin Zhongkun , Hong Guangfu , Chen Mingji , Zhou Mengjing , Li Weiduan , Fang Daining
Published: July 2022

Broadband sound absorption has consistently been a challenge in designing underwater sound absorption structure (USAS). Most research of USASs achieve broadband sound absorption through structural optimization, which curbs the freedom of designing, and commonly alights it at the expense of increased thickness. In this paper, a method is reported to broaden the frequency band of the USAS by embedding a membrane-type resonator into the cavity, which forming a membrane-type underwater acoustic absorption metamaterial. We demonstrate the mechanism of membrane-type metamaterial by theory, and verify it by simulation and experiment. The experimental results show that the sound absorption coefficient in the frequency range of 2000–10 000 Hz is significantly improved after implanting the membrane-type resonator into the cavity. The average sound absorption coefficient is increased by nearly 17%, and the improvement effect of the sound absorption covers to each frequency point, which is consistent with our expectation. As the case of applying membrane-type metamaterials to the design process of underwater acoustic structures, this research possesses great application potential in acoustic wave communication and device compatibility design technologies.
DFT-1/2 and shell DFT-1/2 methods: electronic structure calculation for semiconductors at LDA complexity
Authors: Mao Ge-Qi , Yan Zhao-Yi , Xue Kan-Hao , Ai Zhengwei , Yang Shengxin , Cui Hanli , Yuan Jun-Hui , Ren Tian-Ling , Miao Xiangshui
Published: July 2022

It is known that the Kohn–Sham eigenvalues do not characterize experimental excitation energies directly, and the band gap of a semiconductor is typically underestimated by local density approximation (LDA) of density functional theory (DFT). An embarrassing situation is that one usually uses LDA+U for strongly correlated materials with rectified band gaps, but for non-strongly-correlated semiconductors one has to resort to expensive methods like hybrid functionals or GW. In spite of the state-of-the-art meta-generalized gradient approximation functionals like TB-mBJ and SCAN, methods with LDA-level complexity to rectify the semiconductor band gaps are in high demand. DFT-1/2 stands as a feasible approach and has been more widely used in recent years. In this work we give a detailed derivation of the Slater half occupation technique, and review the assumptions made by DFT-1/2 in semiconductor band structure calculations. In particular, the self-energy potential approach is verified through mathematical derivations. The aims, features and principles of shell DFT-1/2 for covalent semiconductors are also accounted for in great detail. Other developments of DFT-1/2 including conduction band correction, DFT+A-1/2, empirical formula for the self-energy potential cutoff radius, etc, are further reviewed. The relations of DFT-1/2 to hybrid functional, sX-LDA, GW, self-interaction correction, scissor’s operator as well as DFT+U are explained. Applications, issues and limitations of DFT-1/2 are comprehensively included in this review.