bluuebunny/crossref_metadata_2025 huggingface dataset:
Corrosion mechanism and machinability of 7075‐T6 aluminum alloy in high‐speed cutting: With and without cryogenic treatment
Authors: Zhang Ping , Wang Shunxiang , Lin Zhenyong , Liu Zehua , Liu Junling , Mai Qingqun , Yue Xiujie
Published: February 2023

This work aims to explore the effect of cutting parameters on the cutting force, surface quality, and corrosion resistance of 7075‐T6 aluminum alloy after and without cryogenic treatment. Cryogenically treated (T6‐C) and noncryogenically treated (T6) 7075‐T6 aluminum alloy samples are experimentally cut and electrochemically corroded in a 3.5% NaCl solution. SEM, EDS, and electrochemical analysis are carried out to examine how cutting parameters affect the cutting force, surface quality, and corrosion resistance of cryogenically treated 7075‐T6 aluminum alloy. The results show that after cryogenic treatment, under different cutting speeds, the cutting force is up to 39.8% smaller than without cryogenic treatment; under different cutting depths and feed rates, the cutting force is up to 136% and 21.54% smaller, respectively. Cryogenic treatment dramatically reduces the cutting force in the cutting process. As cutting speed increases, machined surface quality becomes better; fewer corrosion products and cracks are induced. When the cutting depth is 1.5 mm, there are fewer plows and micro‐cracks on the machined surface than under other parameters, but cutting depth does not affect corrosion morphology significantly. The size of corrosion products is up to 55 μm smaller. The electrochemical analysis finds that at the cutting speed of 1500 m/min, after cryogenic treatment, the current density is 59.4% smaller than without cryogenic treatment; polarization resistance is 1.68 × 105Ω•cm2 larger. At the cutting depth of 1.5 mm, after cryogenic treatment, the current density is 66.16% smaller; self‐corrosion potential shifts 0.19 V toward the positive pole. At the feed rate of 0.06 mm/z, after cryogenic treatment, self‐corrosion potential shifts 0.18 V toward the positive pole; polarization resistance is 10.7% larger. These parameters correspond to the best corrosion resistance.
Studies on fly ash/coir/sugarcane reinforced epoxy polymer matrix composite
Authors: Gopalan V. , Rajarajan S. , Wilson M. , Venkatesan J. , Elango M. , Natarajan S. , Rajakumar S.
Published: February 2023

In the past years studies were conducted on natural fibre reinforced polymer composites to observe their mechanical properties in order to decide their industrial applications. These composites have already been used in many applications from aerospace to sporting equipment. These green composites can be used as a replacement for synthetic composites. This is because the natural fibres are eco‐friendly, biodegradable, renewable, etc. In this work, an attempt is made to reinforce fly ash, coir fibre and sugarcane fibre with epoxy polymer matrix. Central composite design under response surface methodology (RSM), one of the approaches of design of experiments (DOE) is used to determine optimum sample preparation conditions of fly ash, coir fibre and sugarcane fibre. Both tensile and flexural (three‐point bending) tests are conducted on these fabricated composites to determine their materialistic characteristics. Analysis of variance (ANOVA) is carried out using Minitab software to find the influence of fly ash, coir fibre, sugarcane fibre on composites. Regression equations obtained from analysis of variance is used to calculate values. Experimental and calculated values are compared and their error % are calculated and tabulated. Response surface optimization study is carried to find the optimized parameters of composites. It is observed that, increase in wt.% of coir fibre and decrease in wt.% of fly ash and sugarcane fibre, increases yield stress and these parameters have mixed impact on ultimate tensile stress. The addition of fly ash, coir fibre and sugarcane fibre in low percentages increases Young's modulus. Increase in wt.% of fly ash and coir fibre and decrease in wt.% of sugarcane, increases flexural modulus and flexural stress.
Statistical analysis and recovery behaviors of dislocations in cold‐rolled and annealed reactor pressure vessel steels
Authors: Liu H. , Wang M. , Du B. , Ge X. , Fan B.
Published: February 2023

The statistical analysis and recovery behavior of dislocations in cold‐rolled and annealed reactor pressure vessel steels with a thickness reduction of 50 % were investigated by using x‐ray diffraction and electron backscattered diffraction analysis in this study. A new modified Kubin & Mortensen's method was proposed to evaluate the geometrically necessary dislocation density, and this method could effectively improve the accuracy of geometrically necessary dislocation evaluation by eliminating the effect of step size and measurement noises. Comparison analysis between modified Williamson‐Hall and modified Kubin & Mortensen's methods was also performed in this study, which shows different recovery behavior of dislocations. The electron backscattered diffraction results show that geometrically necessary dislocation density remained unchangeable after annealing treatment below and at 550 °C, and it occurred to decrease above 550 °C due to the occurrence of recrystallization. However, dislocations started to migrate and annihilate at 340 °C according to x‐ray diffraction results. A possible explanation is a difference in the effect of pairwise dislocation annihilation on statistically stored dislocations and geometrically necessary dislocations.
Analysis of an optimal control problem for a spatio‐temporal SIR model with nonlinear density dependent diffusion terms
Authors: Mehdaoui Mohamed , Lamrani Alaoui Abdesslem , Tilioua Mouhcine
Published: February 2023

This paper focuses on the study of an optimal control problem for a new spatio‐temporal SIR epidemic model with nonlinear density dependent diffusion terms and a class of nonlinear incidence functions. We consider two types of control variables, vaccination for the susceptible and treatment for the infected. For fixed controls, by means of Schauder fixed point theorem, we prove that the proposed model admits a weak biologically feasible solution, the uniqueness of the latter is also investigated. Furthermore, using the state and adjoint problems, first order necessary optimal conditions are obtained. Finally, numerical simulations are carried out for particular diffusion terms incorporating the heard mentality of individuals, when it comes to the spatial movement, and for particular incidence functions, as well as by varying the parameters of the objective functional, to illustrate the possible optimal control strategies and their effect on the studied population.
Intraoperative Neck Angles in Endoscopic and Microscopic Otologic Surgeries
Authors: Joo Hyonoo , Lin Zihao , Yesantharao Lekha , Formeister Eric , Razavi Christopher , Patel Millan , Carey John , Taylor Russ , Galaiya Deepa
Published: February 2023

Objective

To quantitatively compare the ergonomic risk of otologic surgeries performed with endoscopes and microscopes.

Study Design

Observational cross‐sectional study.

Setting

Operating room of a tertiary academic medical center.

Methods

Intraoperative neck angles of otolaryngology attendings, fellows, and residents were assessed during 17 otologic surgeries using inertial measurement unit sensors. Sensors were attached midline between the shoulder blades and on the posterior scalp of participants and were calibrated just prior to beginning each case. Quaternion data were used to calculate neck angles during periods of active surgery.

Results

Endoscopic and microscopic cases included similar percentages of time in high‐risk neck positions, 75% and 73%, respectively, according to a validated ergonomic risk assessment tool, the Rapid Upper Limb Assessment. However, microscopic cases included a higher percentage of time spent in extension (25%) compared to endoscopic cases (12%) (p < .001). When examining the magnitude of average flexion and extension angles, endoscopic and microscopic cases were not significantly different.

Conclusion

Utilizing intraoperative sensor data, we found that both endoscopic and microscopic approaches in otologic surgery were associated with high‐risk neck angles, which can result in sustained neck strain. These results suggest that optimal ergonomics may be better achieved by the consistent application of basic ergonomic principles than by changing the technology in the operating room.
Occupational Characteristics Associated with Professional Fulfillment and Burnout Among U.S. Physiatrists
Authors: Makowski Maryam S. , Trockel Mickey , Paganoni Sabrina , Weinstein Stuart , Verduzco‐Gutierrez Monica , Kinney Carolyn , Kennedy David J. , Sliwa James , Wang Hanhan , Knowlton Tiffany , Stautzenbach Tom , Shanafelt Tait D.
Published: February 2023

Introduction

Multiple national studies suggest that, among physicians, physiatrists are at increased risk for occupational burnout.

Objective

To identify characteristics of the work environment associated with professional fulfillment and burnout among U.S. physiatrists.

Design

Between May and December 2021, a mixed qualitative and quantitative approach was used to identify factors contributing to professional fulfillment and burnout in physiatrists.

Setting

Online interviews, focus groups, and survey.

Participants

Physiatrists in the AAPM&R Membership Masterfile.

Main Outcome Measures

Burnout and professional fulfillment assessed using the Stanford Professional Fulfillment Index.

Results

Individual interviews with 21 physiatrists were conducted to identify domains that contributed to professional fulfillment followed by focus groups for further definition. Based on themes identified, scales were identified or developed to evaluate: control over schedule (6 items; Cronbach's alpha = 0.86); integration of physiatry into patient care (3 items; Cronbach's alpha = 0.71); personal‐organizational values alignment (3 items; Cronbach's alpha = 0.90); meaningfulness of physiatrist clinical work (6 items; Cronbach's alpha = 0.90); teamwork and collaboration (3 items; Cronbach's alpha = 0.89). Of 5760 physiatrists contacted in the subsequent national survey, 882 (15.4%) returned surveys (median age 52 years; 46.1% women). Overall, 42.6% (336 of 788) experienced burnout and 30.6% (244 of 798) had high levels of professional fulfillment. In multivariable analysis, each one‐point improvement in control over schedule (odds ratio [OR] = 1.96; 95% confidence interval [CI] = 1.45–2.69), integration of physiatry into patient care (OR = 1.77; 95% CI = 1.32–2.38), personal‐organizational values alignment (OR = 1.92; 95% CI = 1.48–2.52), meaningfulness of physiatrist clinical work (OR = 2.79; 95% CI = 1.71–4.71) and teamwork and collaboration score (OR = 2.11; 95% CI = 1.48–3.03) was independently associated with higher likelihood of professional fulfillment.

Conclusions

Control over schedule, optimal integration of physiatry into clinical care, personal‐organizational values alignment, teamwork, and meaningfulness of physiatrist clinical work are strong and independent drivers of occupational well‐being in U.S. physiatrists. Variation in these domains by practice setting and subspecialty suggests tailored approaches are needed to promote professional fulfillment and reduce burnout among U.S. physiatrists.
Validation of an outpatient questionnaire for bronchopulmonary dysplasia control
Authors: Collaco Joseph M. , Li Yun , Rhein Lawrence M. , Tracy Michael C. , Sheils Catherine A. , Rice Jessica L. , Popova Antonia P. , Moore Paul E. , Manimtim Winston M. , Lai Khanh , Kaslow Jacob A. , Hayden Lystra P. , Bansal Manvi , Austin Eric D. , Aoyama Brianna , Alexiou Stamatia , Agarwal Amit , Villafranco Natalie , Siddaiah Roopa , Lagatta Joanne M. , Dawson Sara K. , Cristea A. Ioana , Bauer Sarah E. , Baker Christopher D. , McGrath‐Morrow Sharon A.
Published: February 2023

Introduction

Despite bronchopulmonary dysplasia (BPD) being a common morbidity of preterm birth, there is no validated objective tool to assess outpatient respiratory symptom control for clinical and research purposes.

Methods

Data were obtained from 1049 preterm infants and children seen in outpatient BPD clinics of 13 US tertiary care centers from 2018 to 2022. A new standardized instrument was modified from an asthma control test questionnaire and administered at the time of clinic visits. External measures of acute care use were also collected. The questionnaire for BPD control was validated in the entire population and selected subgroups using standard methodology for internal reliability, construct validity, and discriminative properties.

Results

Based on the scores from BPD control questionnaire, the majority of caregivers (86.2%) felt their child's symptoms were under control, which did not differ by BPD severity (p = 0.30) or a history of pulmonary hypertension (p = 0.42). Across the entire population and selected subgroups, the BPD control questionnaire was internally reliable, suggestive of construct validity (albeit correlation coefficients were −0.2 to −0.4.), and discriminated control well. Control categories (controlled, partially controlled, and uncontrolled) were also predictive of sick visits, emergency department visits, and hospital readmissions.

Conclusion

Our study provides a tool for assessing respiratory control in children with BPD for clinical care and research studies. Further work is needed to identify modifiable predictors of disease control and link scores from the BPD control questionnaire to other measures of respiratory health such as lung function testing.
Spintronic Heterostructures for Artificial Intelligence: A Materials Perspective
Authors: Maddu Ramu , Kumar Durgesh , Bhatti Sabpreet , Piramanayagam S. N.
Published: February 2023

With the advent of the Big Data era, neuromorphic computing (NC) (also known as brain‐inspired computing) has gained a lot of research interest. Spintronic devices are the emerging candidates for implementing the NC due to their intrinsic nonvolatility, extremely high endurance, low‐power consumption, and complementary metal‐oxide compatibility. Many research groups have proposed various NC architectures based on spintronic devices. Herein, a collective survey of different spintronic‐based approaches is given for NC. The reviewed approaches include the progress of stochastic magnetic tunnel junction (MTJ) devices, spin‐torque nano‐oscillator, spin‐Hall nano‐oscillator, domain walls, and skyrmion devices. In all of these approaches, spin–orbit torque (SOT)‐based magnetization control, which is achieved via spintronics heterostructures, plays a significant role. Various heterostructures of heavy metal and ferromagnetic layers that have been proposed are reviewed for generating SOT. In addition, the phenomena and materials involved in the generation of orbital torque are summarized due to the orbital Hall effect (OHE), which has recently gained researchers’ attention. Finally, an outlook on the opportunities and challenges for spintronic‐based NC hardware is provided, shedding light on its great potential for artificial intelligence (AI) applications.
Three endobronchial white trees in a patient with mild hemoptysis: A rare case of broncholithiasis
Authors: De Pace Cosimo Carlo , Tondo Pasquale , Ciliberti Gianluca Libero , Selmi Massimo , Lacedonia Donato
Published: February 2023

Key message

Broncholithiasis is a rare and most often ignored condition characterized by the presence of calcified or ossified materials in the bronchus. The patient can be asymptomatic or commonly present with coughing. It is important to correctly identify this disease because in many cases it can cause hemoptysis and rarely lithoptysis.
Investigations into the Extraction of Copper (II) using Methyl Isobutyl ketone solvent
Authors: Djebabra Sihem , Rehali Hanane , Mimi Wafa
Published: February 2023

This work concerns the study of the extraction of copper (II) in the perchlorate medium by Bis‐2‐ethylhexyl phosphoric acid (D2EHPA) in methyl isobutyl ketone (MIBK) at 25 °C at different ionic strength (1, 1/6, 1/10 mol kg−1). The stoichiometry of the reaction of extracted complexations was determined by the slope method. The organometallic complexes extracted in the organic phase are of the type CuL2 in methyl isobutyl ketone has unit ionic strength. The organometallic complexes extracted in the organic phase are of the type CuL2ClO4(H2O) or CuL2ClO4 (MIBK)x in methyl isobutyl ketone has different ionic strength Efficiency of the extraction of copper (II) depends on the ionic strength of the aqueous medium. Hence when the ionic strength of the aqueous perchlorate medium increases the extraction of copper (II) increases.
Surface Structure Engineering of Two‐Dimensional Ni(OH)2 with Enhanced Urea Oxidation Performance
Authors: Zhang Yongxing , Wu Pengxuan , Qiao Nanli , Yu Zhengbao , Ma Liang
Published: February 2023

We herein report a facile two‐pot method to prepare a series of the two‐dimensional Ni(OH)2 nanocrystals with varied surface structures via the in‐situ surface transformation derived from Nickel metal‐organic framework (Ni‐MOF) in KOH solution at room temperature. The Ni(OH)2 obtained at the KOH concentration of 0.25 M displayed superior performance among the samples in terms of activities and stability. Further investigation proves that the enhanced urea oxidation reaction (UOR) activities can be ascribed to the cooperation of the larger electrochemical surface area, a faster electronic transfer speed, and a lower transfer resistance on the surface. These findings provide a new route for the rational design and synthesis of advanced electrocatalysts with relatively lower energy consumption that aims to be large‐scale synthesized and utilized in clean energy conversion and applications.
Emerging technologies for cardiac tissue engineering and artificial hearts
Authors: Sun Lingyu , Wang Yu , Xu Dongyu , Zhao Yuanjin
Published: February 2023

Heart diseases, especially cardiovascular diseases, have brought heavy burden on society for their high morbidity and mortality. In clinical, heart transplantation is recognized as an effective strategy to rescue the lives of patients, while it may suffer from lack of donors and possible immune responses. In view of this, tremendous efforts have been devoted to developing alternative strategies to recover the function and promote the regeneration of cardiac tissues. As an emerging field blending cell biology and material science, tissue engineering technique allows the construction of biomimetic living complexes as organ substitutes for heart repair. In this review, we will present the recent progress in cardiac tissue engineering and artificial hearts. After introducing the critical elements in cardiac tissue engineering, we will present advanced fabrication methods to achieve scaffolds with desired micro/nanostructure design as well as the applications of these bioinspired scaffolds. We will also discuss the current dilemma and possible development direction from a biomedical perspective.
Promising Materials for Photocatalysis‐Self‐Fenton System: Properties, Modifications, and Applications
Authors: Wu Yang , Che Huinan , Liu Bin , Ao Yanhui
Published: February 2023

Photocatalysis‐self‐Fenton system (PSFs), which integrates photocatalysis with Fenton technology, is investigated thoroughly in wastewater treatment due to the virtues of no addition of H2O2 and accelerated circulation of Fe2+/Fe3+. Several kinds of materials that mainly include metal‐free graphite carbon nitride (g‐C3N4), metal oxides (Fe3O4), and metal sulfide (CdS, FeS2) have demonstrated extensive development potential. Nevertheless, most of the developed catalysts are unable to satisfy the requirements of PSFs. Therefore, a comprehensive review committed to the materials and modification methods in PSFs is put forward. First, the concrete mechanism of PSFs from two aspects of photocatalysis and Fenton reaction is discussed. Second, the properties, modifications (morphology modulation, heterojunction construction as well as doping), and applications (contaminants degradation and disinfection) of the promising catalysts are emphasized. Finally, the novel directions for future research in PSFs are looked forward to. This review opens up a new horizon for enhancing the practical application of PSFs in future.
Description and systematic affinity of flower and seed fossils of Erica sect. Chlorocodon (Ericaceae) from the early Pleistocene of Madeira Island, Portugal
Authors: Góis‐Marques Carlos A. , de Nascimento Lea , Fernández‐Palacios José María , Madeira José , de Sequeira Miguel Menezes
Published: February 2023

Palaearctic Erica sect. Chlorocodon, known as the wind‐pollinated besom heaths (WPBH), includes the Macaronesian E. azorica, E. platycodon subsp. platycodon and E. platycodon subsp. maderincola together with the Mediterranean and North African E. scoparia. Despite the broad extant distribution, the mainland fossil record of this section is scarce and poorly preserved and dated, and Macaronesian fossils were so far unknown. Here we discuss the systematic affinities of the first fossils of a WPBH found in Macaronesia, within a 1.3 Ma (Pleistocene, Calabrian stage) Madeira Island fossiliferous deposit. One flower and dissociated seed fossils were found in the same sediment layer, being preserved as coalified compressions with cuticular preservation. Both the flower and seed fossils present unique WPBH characters. The flower fossil is characterised by an exserted, peltate and discoid stigma – an unequivocal adaptation to anemophily, unique within Palaearctic Erica taxa. The seed fossils are of small size, presenting a testa with channelled anticlinal cell‐walls, a characteristic only found in the extant Macaronesian WPBH. Morphological, anatomical, and biometric comparisons of the fossils to extant flowers and seeds suggest that the fossils are related to the Palaearctic E. sect. Chlorocodon, being morphologically close to E. azorica. Here we assign them to E. aff. azorica. These findings suggest a colonisation to Madeira Island prior to 1.3 Ma, corresponding to the oldest and unambiguous WPBH fossils, at least 0.90–1.2 Ma older than the oldest known record. The fossil flower also indicates the presence of anemophilous traits since at least the early Pleistocene. Finally, the presence of a WPBH could suggest the same ecological role in seral communities, important to the establishment of the Madeiran temperate stink‐laurel forest.
Branch angle and leaflet shape are associated with canopy coverage in soybean
Authors: Virdi Kamaldeep S. , Sreekanta Suma , Dobbels Austin , Haaning Allison , Jarquin Diego , Stupar Robert M. , Lorenz Aaron J. , Muehlbauer Gary J.
Published: February 2023

Early canopy coverage is a desirable trait that is a major determinant of yield in soybean (Glycine max). Variation in traits comprising shoot architecture can influence canopy coverage, canopy light interception, canopy‐level photosynthesis, and source‐sink partitioning efficiency. However, little is known about the extent of phenotypic diversity of shoot architecture traits and their genetic control in soybean. Thus, we sought to understand the contribution of shoot architecture traits to canopy coverage and to determine the genetic control of these traits. We examined the natural variation for shoot architecture traits in a set of 399 diverse maturity group I soybean (SoyMGI) accessions to identify relationships between traits, and to identify loci that are associated with canopy coverage and shoot architecture traits. Canopy coverage was correlated with branch angle, number of branches, plant height, and leaf shape. Using previously collected 50K single nucleotide polymorphism data, we identified quantitative trait locus (QTL) associated with branch angle, number of branches, branch density, leaflet shape, days to flowering, maturity, plant height, number of nodes, and stem termination. In many cases, QTL intervals overlapped with previously described genes or QTL. We also found QTL associated with branch angle and leaflet shape located on chromosomes 19 and 4, respectively, and these QTL overlapped with QTL associated with canopy coverage, suggesting the importance of branch angle and leaflet shape in determining canopy coverage. Our results highlight the role individual architecture traits play in canopy coverage and contribute information on their genetic control that could help facilitate future efforts in their genetic manipulation.
Charged lepton flavor violating radiative decays li → ljγ in G2HDM
Authors: Tran Van Que , Yuan Tzu-Chiang
Published: February 2023

Abstract

We compute the electromagnetic form factors of the liljγ vertex at one-loop level in the minimal G2HDM which has a sub-GeV vector dark matter candidate. The results are applied to the radiative decay rates for the charged lepton flavor violating processes li → ljγ, and the anomalous magnetic dipole moment and the electric dipole moment of the charged lepton. To numerically compute the branching ratio for μ → eγ and compare with the latest experimental limit from MEG, we adapt our previous parameter space scan that is consistent with the relic density and constraints from direct searches of dark matter, W and Z mass measurements, as well as the LHC Higgs signal strengths and invisible width. While the extra contributions are at least an order of magnitude smaller than required to explain the ~4.2σ discrepancy in the muon anomaly, the existing MEG limit imposes stringent constraint on the parameter space. The remaining viable parameter space can be further probed by the MEG II sensitivity for μ → eγ as well as from the direct searches of sub-GeV dark matter in foreseeable future. Higher loop contributions may be significant to resolve the discrepancy in the muon anomaly and generate a non-vanishing electric dipole moments for the standard model quarks and leptons in G2HDM.
Non-BPS bubbling geometries in AdS3
Authors: Bah Ibrahima , Heidmann Pierre
Published: February 2023

Abstract

We construct large classes of non-BPS smooth horizonless geometries that are asymptotic to AdS3 × S3 × T4 in type IIB supergravity. These geometries are supported by electromagnetic flux corresponding to D1-D5 charges. We show that Einstein equations for systems with eight commuting Killing vectors decompose into a set of Ernst equations, thereby admitting an integrable structure. This feature, which can a priori be applied to other $$ {\textrm{AdS}}_D\times \mathcal{C} $$

AdS
D

×
C
settings in supergravity, allows us to use solution-generating techniques associated with the Ernst formalism. We explicitly derive solutions by applying the charged Weyl formalism that we have previously developed. These are sourced internally by a chain of bolts that correspond to regions where the orbits of the commuting Killing vectors collapse smoothly. We show that these geometries can be interpreted as non-BPS T4 and S3 deformations on global AdS3 × S3 × T4 that are located at the center of AdS3. These non-BPS deformations can be made arbitrarily small and should therefore correspond to non-supersymmetric operators in the D1-D5 CFT. Finally, we also construct interesting bound states of non-extremal BTZ black holes connected by regular bolts.
A seesaw model for large neutrino masses in concordance with cosmology
Authors: Escudero Miguel , Schwetz Thomas , Terol-Calvo Jorge
Published: February 2023

Abstract

Cosmological constraints on the sum of the neutrino masses can be relaxed if the number density of active neutrinos is reduced compared to the standard scenario, while at the same time keeping the effective number of neutrino species Neff ≈ 3 by introducing a new component of dark radiation. We discuss a UV complete model to realise this idea, which simultaneously provides neutrino masses via the seesaw mechanism. It is based on a U(1) symmetry in the dark sector, which can be either gauged or global. In addition to heavy seesaw neutrinos, we need to introduce 𝒪(10) generations of massless sterile neutrinos providing the dark radiation. Then we can accommodate active neutrino masses with ∑mν ~ 1 eV, in the sensitivity range of the KATRIN experiment. We discuss the phenomenology of the model and identify the allowed parameter space. We argue that the gauged version of the model is preferred, and in this case the typical energy scale of the model is in the 10 MeV to few GeV range.
Going off topics to demix quark and gluon jets in αS extractions
Authors: LeBlanc Matt , Nachman Benjamin , Sauer Christof
Published: February 2023

Abstract

Quantum chromodynamics is the theory of the strong interaction between quarks and gluons; the coupling strength of the interaction, αS, is the least precisely-known of all interactions in nature. An extraction of the strong coupling from the radiation pattern within jets would provide a complementary approach to conventional extractions from jet production rates and hadronic event shapes, and would be a key achievement of jet substructure at the Large Hadron Collider (LHC). Presently, the relative fraction of quark and gluon jets in a sample is the limiting factor in such extractions, as this fraction is degenerate with the value of αS for the most well-understood observables. To overcome this limitation, we apply recently proposed techniques to statistically demix multiple mixtures of jets and obtain purified quark and gluon distributions based on an operational definiton. We illustrate that studying quark and gluon jet substructure separately can significantly improve the sensitivity of such extractions of the strong coupling. We also discuss how using machine learning techniques or infrared- and collinear-unsafe information can improve the demixing performance without the loss of theoretical control. While theoretical research is required to connect the extract topics with the quark and gluon objects in cross section calculations, our study illustrates the potential of demixing to reduce the dominant uncertainty for the αS extraction from jet substructure at the LHC.
Nonrelativistic approximations of closed bosonic string theory
Authors: Hartong Jelle , Have Emil
Published: February 2023

Abstract

We further develop the string 1/c2 expansion of closed bosonic string theory, where c is the speed of light. The expansion will be performed up to and including the next-to-next-to-leading order (NNLO). We show that the next-to-leading order (NLO) theory is equal to the Gomis-Ooguri string, generalised to a curved target space, provided the target space geometry admits a certain class of co-dimension-2 foliations. We compute the energy of the string up to NNLO for a flat target space with a circle that must be wound by the string, and we show that it agrees with the 1/c2 expansion of the relativistic energy. We also compute the algebra of Noether charges for a flat target space and show that this matches order-by-order with an appropriate expansion of the Poincaré algebra, which at NLO gives the string Bargmann algebra. Finally, we expand the phase space action, which allows us to perform the Dirac procedure and pass to the quantum theory. It turns out that the Poisson brackets change at each order, and we show that the normal ordering constant of the relativistic theory, which does not depend on c, can be reproduced by the NLO and NNLO theories.
Celestial amplitudes in an ambidextrous basis
Authors: Jorge-Diaz Carmen , Pasterski Sabrina , Sharma Atul
Published: February 2023

Abstract

We start by constructing a conformally covariant improvement of the celestial light transform which keeps track of the mixing between incoming and outgoing states under finite Lorentz transformations in ℝ2,2. We then compute generic 2, 3 and 4-point celestial amplitudes for massless external states in the ambidextrous basis prepared by composing this SL(2,ℝ) intertwiner with the usual celestial map between momentum and boost eigenstates. The results are non-distributional in the celestial coordinates (z,$$ \overline{z} $$z¯) and conformally covariant in all scattering channels. Finally, we focus on the tree level 4-gluon amplitude where we present a streamlined route to the ambidextrous correlator based on Grassmannian formulae and examine its alpha space representation. In the process, we gain insights into the operator dictionary and CFT data of the holographic dual.
Callan-Rubakov effect and higher charge monopoles
Authors: Brennan T. Daniel
Published: February 2023

Abstract

In this paper we study the interaction between magnetic monopoles and massless fermions. In the low energy limit, the monopole’s magnetic field polarizes the fermions into purely in-going and out-going modes. Consistency requires that the UV fermion-monopole interaction leads to non-trivial IR boundary conditions that relate the in-going to out-going modes. These non-trivial boundary conditions lead to what is known as the Callan-Rubakov effect. Here we derive the effective boundary condition by explicitly integrating out the UV degrees of freedom for the general class of spherically symmetric SU(N) monopoles coupled to massless fermions of arbitrary representation. We then show that the boundary conditions preserve symmetries without ABJ-type anomalies. As an application we explicitly derive the boundary conditions for the stable, spherically symmetric monopoles associated to the SU(5) Georgi-Glashow model and comment on the relation to baryon number violation.
Conformal (p, q) supergeometries in two dimensions
Authors: Kuzenko Sergei M. , Raptakis Emmanouil S. N.
Published: February 2023

Abstract

We propose a superspace formulation for conformal (p, q) supergravity in two dimensions as a gauge theory of the superconformal group OSp0(p|2; ℝ) × OSp0(q|2; ℝ) with a flat connection. Upon degauging of certain local symmetries, this conformal superspace is shown to reduce to a conformally flat SO(p) × SO(q) superspace with the following properties: (i) its structure group is a direct product of the Lorentz group and SO(p) × SO(q); and (ii) the residual local scale symmetry is realised by super-Weyl transformations with an unconstrained real parameter. As an application of the formalism, we describe $$ \mathcal{N} $$
N
-extended AdS superspace as a maximally symmetric supergeometry in the p = q ≡ $$ \mathcal{N} $$
N
case. If at least one of the parameters p or q is even, alternative superconformal groups and, thus, conformal superspaces exist. In particular, if p = 2n, a possible choice of the superconformal group is SU(1, 1|n) × OSp0(q|2; ℝ), for n ≠ 2, and PSU(1, 1|2) × OSp0(q|2; ℝ), when n = 2. In general, a conformal superspace formulation is associated with a supergroup G = GL× GR, where the simple supergroups GL and GR can be any of the extended superconformal groups, which were classified by Günaydin, Sierra and Townsend. Degauging the corresponding conformal superspace leads to a conformally flat HL× HR superspace, where HL (HR) is the R-symmetry subgroup of GL (GR). Additionally, for the p, q ≤ 2 cases we propose composite primary multiplets which generate the Gauss-Bonnet invariant and supersymmetric extensions of the Fradkin-Tseytlin term.
D=5 holomorphic Chern-Simons and the pure spinor superstring
Authors: Berkovits Nathan
Published: February 2023

Abstract

The physical states of D=5 holomorphic Chern-Simons theory correspond to on-shell D=10 open superstring states in the cohomology of q+, where q+ is one of the 16 spacetime supersymmetry generators. Scattering amplitudes of these states can be computed either using the usual Ramond-Neveu-Schwarz (RNS) superstring prescription with N=1 worldsheet supersymmetry, or using a topological ĉ=5 string theory with twisted N=2 worldsheet supersymmetry.

It will be argued that the relation between D=5 holomophic Chern-Simons and the RNS superstring is identical to the relation between the pure spinor superstring and the recently constructed B-RNS-GSS superstring which has both N=1 worldsheet supersymmetry and D=10 spacetime supersymmetry. Physical states of the pure spinor superstring correspond to on-shell B-RNS-GSS states which are in the cohomology of λαqα, where λα is a D=10 pure spinor. And scattering amplitudes of these states can be computed either using the full B-RNS-GSS superstring prescription with N=1 worldsheet supersymmetry, or using the pure spinor superstring amplitude prescription with twisted N=2 worldsheet supersymmetry. This should be useful for proving equivalence of the RNS and pure spinor amplitude prescriptions and for clarifying the relation of their multiloop subtleties.
Immunmodulation durch Ernährung bei kritisch kranken Patienten
Authors: Hirschberger Simon , Schmid Annika , Kreth Simone
Published: February 2023

Kritisch kranke Patienten leiden häufig unter einer komplexen und schwerwiegenden immunologischen Dysfunktion. Die Differenzierung und Funktion von Immunzellen werden maßgeblich durch metabolische Prozesse gesteuert. Neue immunonutritive Konzepte versuchen daher, die Immunfunktionen intensivmedizinischer Patienten über enterale und parenterale Ernährung positiv zu beeinflussen. Die vorliegende Übersichtsarbeit präsentiert kondensiert die verfügbare Evidenz zu den gängigen isolierten Supplementen (antioxidative Substanzen, Aminosäuren, essenzielle Fettsäuren) und die damit verbundenen Problematiken. Im zweiten Teil werden sich daraus ergebende neuartige und umfassendere Konzepte der Immunonutrition zur Beeinflussung des intestinalen Mikrobioms und zur Modulation der Makronährstoffkomposition vorgestellt. Die Immunonutrition des kritisch kranken Patienten hat enormes Potenzial und kann sich zukünftig zu einem wertvollen klinischen Tool zur Modulation des Immunmetabolismus intensivmedizinischer Patienten entwickeln.
The five tests: designing and evaluating AI according to indigenous Māori principles
Authors: Munn Luke
Published: February 2023

As AI technologies are increasingly deployed in work, welfare, healthcare, and other domains, there is a growing realization not only of their power but of their problems. AI has the capacity to reinforce historical injustice, to amplify labor precarity, and to cement forms of racial and gendered inequality. An alternate set of values, paradigms, and priorities are urgently needed. How might we design and evaluate AI from an indigenous perspective? This article draws upon the five Tests developed by Māori scholar Sir Hirini Moko Mead. This framework, informed by Māori knowledge and concepts, provides a method for assessing contentious issues and developing a Māori position. This paper takes up these tests, considers how each test might be applied to data-driven systems, and provides a number of concrete examples. This intervention challenges the priorities that currently underpin contemporary AI technologies but also offers a rubric for designing and evaluating AI according to an indigenous knowledge system.
Identification of the process damping coefficient in dry and wet machining of steel
Authors: Denkena Berend , Bergmann Benjamin , Ellersiek Lars
Published: February 2023

Flank face chamfers are an effective way to suppress vibrations and increase the productivity of milling processes. The underlying process damping mechanism is the so-called indentation effect. The effect describes the process damping as a result of an additional force due to the indentation of workpiece material under the flank face. In literature, this force is commonly modeled by the volume indented under the flank face and a process damping coefficient. To determine the process damping coefficient, various approaches with partly contradictory results exist. In this paper, a novel method to calculate the process damping coefficient based on process forces measurements in orthogonal cutting is applied for steel machining. The method considers ploughing effects of flank face chamfer and cutting edge rounding as well as plastic deformation effects. In the current investigation, the approach is applied to different cooling strategies, chamfer widths, and cutting speeds. The results show that the cutting speed has the most significant influence on the process damping coefficient. With increasing cutting speed, the process damping coefficient increases, which can be attributed to strain rate hardening effects.
Irritation from metalwork after ankle arthrodesis fixed using screws: a proportional meta-analysis and systematic review
Authors: Izzo Antonio , Sgadari Arianna , Santagata Salvatore , Coviello Antonio , Cozzolino Andrea , Mariconda Massimo , Bernasconi Alessio
Published: February 2023

Objective

Ankle arthrodesis (AA) is often fixed using cannulated screws. The irritation from metalwork is a relatively common complication, but there is no consensus regarding the need to remove the screws on a systematic basis. The aim of this study was to determine (1) the proportion of screws removed after AA and (2) whether predictors of screw removal could be identified.

Methods

This PRISMA-compliant systematic review was part of a larger previous protocol registered on the PROSPERO platform. Multiple databases were searched including studies in which patients undergone AA using screws as exclusive fixation method were followed. Data were harvested regarding the cohort, the study design, the surgical technique, the nonunion and complication rate at the longest follow-up. Risk of bias was assessed using the modified Coleman Methodology Score (mCMS).

Results

Forty-four series of patients from thirty-eight studies (1990 ankles, 1934 patients) were selected. The average follow-up was 40.8 months (range 12–110). In all studies, hardware was removed due to symptoms reported by patients and related to the screws. The pooled proportion of removal of metalwork was 3% (95% CI 2–4). The pooled proportion of fusion was 96% (95%CI 95–98), while the pooled proportion of complications and reoperations (excluding the removal of metalwork) stood at 15% (95% CI 11–18) and 3% (95% CI 2–4), respectively. The mean mCMS (50.8 ± 8.1, range 35–66) revealed only an overall fair quality of studies. The univariate analysis and the multivariate model showed that the year of publication (R = − 0.004; p = 0.01) and the number of screws (R = 0.08; p = 0.01) were associated with the screw removal rate. Specifically, we found that over time the removal rate decreased by 0.4% per year and that the use of three screws instead of two reduced the risk of removal of metalwork by 8%.

Conclusions

In this review, removal of metalwork after ankle arthrodesis using cannulated screws was needed in 3% of cases at an average follow-up of 40.8 months. It was indicated only in case of symptoms related to soft tissue irritation from screws. The use of three screws was paradoxically related to a reduced risk of removal of screws as compared to two-screw constructs.

Level of evidence

Level IV, systematic review of Level IV.
High estradiol levels during a long agonist IVF protocol are associated with decreased food intake, higher leptin concentrations, and lower levels of high-sensitivity C-reactive protein
Authors: Leppänen Jonna , Nuotio Petrus , Randell Kaisa , Romppanen Jarkko , Keski-Nisula Leea , Laitinen Tomi , Pihlajamäki Jussi , Schwab Ursula , Heinonen Seppo
Published: February 2023

Purpose

To study whether different hormonal phases affect appetite regulation, food intake, and concentrations of leptin, glucagon-like peptide-1 (GLP-1), and high-sensitivity C-reactive protein (hs-CRP) during a long agonist in vitro fertilization (IVF) protocol.

Methods

Fifty-four infertile women were encountered thrice, the first of which was at the beginning of their period (low estradiol). The other two visits were during a gonadotrophin-releasing hormone (GnRH) analog downregulation (low estradiol) and at the end of a follicle-stimulating hormone (FSH) stimulation (high estradiol). The first visit was the reference; the women served as their controls. The concentrations of leptin, GLP-1, and hs-CRP were assessed from plasma. Dietary intake was assessed using food records (FRs). In addition, weight, height, body mass index (BMI), and plasma levels of estradiol, glucose, HbA1c, insulin, and lipids were monitored. Twenty-six of the subjects also had a postprandial test.

Results

During the stimulation protocol, leptin concentrations elevated (P < 0.001), and energy intake decreased (P = 0.03), while estradiol levels increased (P < 0.001). GLP-1 levels unchanged (P = 0.75) and hs-CRP (P = 0.03) concentrations diminished, while estradiol levels increased.

Conclusion

No increased food intake or weight gain occurred during the stimulation protocol; thus, leptin may protect from overeating during high estradiol levels, and leptin resistance may not occur during a short follow-up. Also, a favorable anti-inflammatory effect was detected. During this study, we observed no harmful metabolic effects, which might affect negatively maternal health.
A clinical case of enzootic bovine leukosis diagnosed by using clonal analysis of peripheral B lymphocytes in a Japanese Black cow
Authors: Inokuma Hisashi , Nagata Tatsuki , Maezawa Masaki , Watanabe Ken-ichi , Kobayashi Yoshiyasu , Kojima Kazuhiro , Chambers James K. , Uchida Kazuyuki
Published: February 2023

A 7-year-old Japanese Black cow with anorexia was presented at a local veterinarian. As rectal palpation revealed an enlarged induration of the uterus, lymphoma was suspected, and the patient was introduced to the Veterinary Teaching Hospital of Obihiro University of Agriculture and Veterinary Medicine. Although lymphadenopathy and lymphocytosis were not found, a high proviral load of bovine leukemia virus (BLV) with 464 copies/10 ng DNA was recorded, and lymphocytes with constricted or flower-like nuclei were found occasionally in the peripheral blood; accordingly, enzootic bovine leukosis (EBL) was suspected. According to PCR for clonality analysis of B cells based on immunoglobulin heavy chain (IGH) gene rearrangement, monoclonal proliferation of peripheral blood B cells was evident, suggesting the presence of tumorigenic B cells in the peripheral blood and onset of EBL. Pathological examination including necropsy and histopathological examination confirmed the diagnosis of EBL. Clonality analysis for B cells in the peripheral blood is thought to be useful for diagnosing B-cell tumors such as EBL, especially in cases lacking lymphadenopathy and lymphocytosis. This is the first clinical case of EBL diagnosed by demonstrating monoclonal proliferation of peripheral blood B cells using IGH gene rearrangement-based PCR.
High Spectral and Temporal Acuity in Primary Auditory Cortex of Awake Cats
Authors: Middlebrooks John C. , Javier-Tolentino Lauren K. , Arneja Akshat , Richardson Matthew L.
Published: February 2023

Most accounts of single- and multi-unit responses in auditory cortex under anesthetized conditions have emphasized V-shaped frequency tuning curves and low-pass sensitivity to rates of repeated sounds. In contrast, single-unit recordings in awake marmosets also show I-shaped and O-shaped response areas having restricted tuning to frequency and (for O units) sound level. That preparation also demonstrates synchrony to moderate click rates and representation of higher click rates by spike rates of non-synchronized tonic responses, neither of which are commonly seen in anesthetized conditions. The spectral and temporal representation observed in the marmoset might reflect special adaptations of that species, might be due to single- rather than multi-unit recording, or might indicate characteristics of awake-versus-anesthetized recording conditions. We studied spectral and temporal representation in the primary auditory cortex of alert cats. We observed V-, I-, and O-shaped response areas like those demonstrated in awake marmosets. Neurons could synchronize to click trains at rates about an octave higher than is usually seen with anesthesia. Representations of click rates by rates of non-synchronized tonic responses exhibited dynamic ranges that covered the entire range of tested click rates. The observation of these spectral and temporal representations in cats demonstrates that they are not unique to primates and, indeed, might be widespread among mammalian species. Moreover, we observed no significant difference in stimulus representation between single- and multi-unit recordings. It appears that the principal factor that has hindered observations of high spectral and temporal acuity in the auditory cortex has been the use of general anesthesia.