bluuebunny/crossref_metadata_2025_split huggingface dataset:
Automatic generation of macromodels and design equations for application to Op Amp design
Authors: Shi Guoyong 
Published: June 2023

SummaryOperational amplifier (Op Amp) is a special class of analog integrated circuits. Multiple‐stage Op Amp design is of particular interest recently. However, analysis of this class of circuits has to be done manually and requires advanced skills. Automatic analysis of this class of circuits is studied in this paper, which takes a novel approach by circuit recognition and symbolic generation. Circuit recognition is deterministic, implemented by deterministic circuit partitioning and functional block extraction methods. Symbolic analysis of extracted circuit blocks can subsequently be performed with greatly reduced complexity while generated models and equations bear more useful information for circuit design. Symbolic results so generated can be applied in design space exploration, including tasks like finding the limitation in circuit topology, conducting initial sizing, and determining performance tradeoffs. This paper proposes the key algorithms for realizing the recognition of a few well‐known functional blocks frequently used in CMOS Op Amp circuits and further explores the possibility of using the recognized circuit cells in combination with the gm/ID method for circuit sizing. Preliminary tests show that this approach is a potential candidate for locating the performance boundaries of multiple‐stage Op Amps.
Impact of different destocking strategies on the resilience of dry rangelands
Authors: Vignal Toyo , Baudena Mara , Mayor Angeles Garcia , Sherratt Jonathan A. 
Published: May 2023

AbstractHalf of the world's livestock live in (semi‐)arid regions, where a large proportion of people rely on animal husbandry for their survival. However, overgrazing can lead to land degradation and subsequent socio‐economic crises. Sustainable management of dry rangeland requires suitable stocking strategies and has been the subject of intense debate in the last decades. Our goal is to understand how variations in stocking strategies affect the resilience of dry rangelands. We describe rangeland dynamics through a simple mathematical model consisting of a system of coupled differential equations. In our model, livestock density is limited only by forage availability, which is itself limited by water availability. We model processes typical of dryland vegetation as a strong Allee effect, leading to bistability between a vegetated and a degraded state, even in the absence of herbivores. We study analytically the impact of varying the stocking density and the destocking adaptivity on the resilience of the system to the effects of drought. By using dynamical systems theory, we look at how different measures of resilience are affected by variations in destocking strategies. We find that the following: (1) Increasing stocking density decreases resilience, giving rise to an expected trade‐off between productivity and resilience. (2) There exists a maximal sustainable livestock density above which the system can only be degraded. This carrying capacity is common to all strategies. (3) Higher adaptivity of the destocking rate to available forage makes the system more resilient: the more adaptive a system is, the bigger the losses of vegetation it can recover from, without affecting the long‐term level of productivity. The first two results emphasize the need for suitable dry rangeland management strategies, to prevent degradation resulting from the conflict between profitability and sustainability. The third point offers a theoretical suggestion for such a strategy.
Corridor quality buffers extinction under extreme droughts in experimental metapopulations
Authors: Li Dongbo , Memmott Jane , Clements Christopher F. 
Published: June 2023

AbstractCorridors with good‐quality habitats maintain the spatial dynamics of metapopulations by promoting dispersal between habitat patches, potentially buffering populations, and communities against continued global change. However, this function is threatened by habitats becoming increasingly fragmented, and habitat matrices becoming increasingly inhospitable, potentially reducing the resilience and persistence of populations. Yet, we lack a clear understanding of how reduced corridor quality interacts with rates of environmental change to destabilize populations. Using laboratory microcosms containing metapopulations of the Collembola Folsomia candida, we investigate the impact of corridor quality on metapopulation persistence under a range of simulated droughts, a key stressor for this species. We manipulated both drought severity and the number of patches affected by drought across landscapes connected by either good‐ or poor‐quality corridors. We measured the time of metapopulation extinction, the maximum rate of metapopulation decline, and the variability of abundance among patches as criteria to evaluate the persistence ability of metapopulations. We show that while drought severity negatively influenced the time of metapopulation extinction and the increase in drought patches caused metapopulation decline, these results were mitigated by good‐quality corridors, which increased metapopulation persistence time and decreased both how fast metapopulations declined and the interpatch variability in abundances. Our results suggest that enhancing corridor quality can increase the persistence of metapopulations, increasing the time available for conservation actions to take effect, and/or for species to adapt or move in the face of continued stress. Given that fragmentation increases the isolation of habitats, improving the quality of habitat corridors may provide a useful strategy to enhance the resistance of spatially structured populations.
Optimal segmentation of Halbach sphere
Authors: Nishimura Kazuhiro 
Published: May 2023

AbstractThe direction of magnetization in which the magnetic field becomes the strongest in the x‐axis direction in the spherical coordinate system is used. Its magnetic field depends on the φ direction in the spherical coordinate system, that is, strongest at the top (φ = 0) and the bottom (φ = π), and the side (φ = π⁄2) becomes the weakest. Therefore, when segmenting, it was divided to include the top and the bottom parts. In addition, in order to make it an optimal segmentation, it is effective to make the range of the top and bottom divisions wide, the sides narrow, and the direction of magnetization close to the top and the bottom directions. By optimizing in this way, the magnetic field is larger than the equal division. For example, it was about 1.09 times stronger in three divisions. This was confirmed by the experiment. However, there is a problem that the demagnetic field in the center becomes strong by optimizing. The type of division which is strong in this problem is also introduced.
Towards multivariate functional trait syndromes: Predicting foliar water uptake in trees
Authors: Chin Alana R. O. , Guzmán‐Delgado Paula , Görlich Anna , HilleRisLambers Janneke 
Published: May 2023

AbstractAnalysis of functional traits is a cornerstone of ecology, yet individual traits seldom explain useful amounts of variation in species distribution or climatic tolerance, and their functional significance is rarely validated experimentally. Multivariate suites of interacting traits could build an understanding of ecological processes and improve our ability to make sound predictions of species success in our rapidly changing world. We use foliar water uptake capacity as a case study because it is increasingly considered to be a key functional trait in plant ecology due to its importance for stress‐tolerance physiology. However, the traits behind the trait, that is, the features of leaves that determine variation in foliar water uptake rates, have not been assembled into a widely applicable framework for uptake prediction. Focusing on trees, we investigated relationships among 25 structural traits, leaf osmotic potential (a source of free energy to draw water into leaves), and foliar water uptake in 10 diverse angiosperm and conifer species. We identified consistent, multitrait “uptake syndromes” for both angiosperm and conifer trees, with differences in key traits revealing suspected differences in the water entry route between these two clades and an evolutionarily significant divergence in the function of homologous structures. A literature review of uptake‐associated functional traits, which largely documents similar univariate relationships, provides additional support for our proposed “uptake syndrome.” Importantly, more than half of shared traits had opposite‐direction influences on the capacity of leaves to absorb water in angiosperms and conifers. Taxonomically targeted multivariate trait syndromes provide a useful tool for trait selection in ecological research, while highlighting the importance of micro‐traits and the physiological verification of their function for advancing trait‐based ecology.
Rhodium‐Catalyzed Dearomative 1,4‐Acyl Rearrangement of 2‐Oxypyridines with Hydrazones: Access to N‐Substituted 2‐Pyridones
Authors: Ni Yifeng , Sun Jiangtao 
Published: May 2023

AbstractA rhodium‐catalyzed dearomative 1,4‐acyl migratory rearrangement reaction of 2‐oxypyridines has been developed for the direct synthesis of 2‐alkylated pyridones under mild reaction conditions. Different with the former reports, in this protocol, readily accessible and bench stable vinyl N‐nosylhydrazones instead of diazoacetates have been used as carbene precursors. As a result, a range of N‐alkylated pyridones have been prepared in acceptable yields with good functional group tolerance.
Necessity for surveillance for hepatocellualr carcinoma in older patients with chronic hepatitis C who achieved sustained virological response
Authors: Ishido Shun , Tamaki Nobuharu , Kurosaki Masayuki , Mori Nami , Tsuji Keiji , Hasebe Chitomi , Mashiba Toshie , Ochi Hironori , Yasui Yutaka , Akahane Takehiro , Furuta Koichiro , Kobashi Haruhiko , Fujii Hideki , Ishii Toru , Marusawa Hiroyuki , Kondo Masahiko , Kusakabe Atsunori , Yoshida Hideo , Uchida Yasushi , Tada Toshifumi , Nakamura Shinichiro , Mitsuda Akari , Ogawa Chikara , Arai Hirotaka , Murohisa Toshimitsu , Uebayashi Minoru , Izumi Namiki 
Published: May 2023

AbstractBackground and AimHepatocellular carcinoma (HCC) surveillance in low‐risk patients (annual incidence <1.5%) is not recommended per the American Association for the Study of Liver Diseases guidelines. Because patients with chronic hepatitis C with non‐advanced fibrosis who have achieved sustained virological response (SVR) have a low risk of HCC, HCC surveillance is not recommended for them. However, aging is a risk factor for HCC; threfore, the necessity for HCC surveillance in older patients with non‐advanced fibrosis needs to be verified.MethodsThis multicenter, prospective study enrolled 4993 patients with SVR (1998 patients with advanced fibrosis and 2995 patients with non‐advanced fibrosis). The HCC incidence was examined with particular attention to age.ResultsThe 3‐year incidence of HCC in patients with advanced and non‐advanced fibrosis was 9.2% (95% CI: 7.8–10.9) and 2.9% (95% CI: 2.1–3.7), respectively. HCC incidence was significantly higher in patients with advanced fibrosis (P < 0.001). HCC incidence stratified by age and sex was investigated in patients with non‐advanced fibrosis. The HCC incidence in the 18–49, 50s, 60s, 70s, and ≥80 age groups were 0.26, 1.3, 1.8, 1.7, and 2.9 per 100 person‐years in men, and 0.00, 0.32, 0.58, 0.49, and 0.57 per 100 person‐years in women, respectively.ConclusionsMale patients with non‐advanced fibrosis aged ≥60 years have a higher risk of developing HCC and, thus, require HCC surveillance.
Molecular epidemiology and disease severity of influenza virus infection in patients with haematological disorders
Authors: Ünal Silan , Schnitzler Paul , Giesen Nicola , Wedde Marianne , Dürrwald Ralf , Tabatabai Julia 
Published: May 2023

AbstractInfluenza virus infection is a common cause of self‐limiting respiratory tract infection (RTI), however immunocompromised patients are at an increased risk for a severe course of disease or fatal outcome. We therefore aimed to gain a better understanding of the molecular epidemiology of influenza viruses from patients with haematological disorders and their impact on the clinical course of disease. Molecular analysis using polymerase chain reaction (PCR) of nasopharyngeal swabs was performed for influenza virus in haematological patients at the Heidelberg University Hospital. Clinical data was evaluated to identify associated risk factors. For phylogenetic analysis, the hemagglutinin (HA) gene was sequenced. Out of 159 influenza positive patients, 117 patients developed upper RTI (influenza A: n = 73; influenza B: n = 44). Lower RTI was observed in n = 42 patients (26%), n = 22/42 patients developed severe disease and n = 16/159 (10.1%) patients died. Risk factors for lower RTI were nosocomial infection (p = 0.02), viral shedding for ≥14 days (p = 0.018), IgG levels <6 g/dL (p = 0.046), bacterial/fungal co‐infections (p < 0.001). Risk factors for fatal outcome were age ≥65 years (p = 0.032), bacterial/fungal (p≤0.001) co‐infections and high viral load (p = 0.026). Sequencing of the HA gene (n = 115) revealed subtype A(H3N2) (n = 46), A(H1N1)pdm09 (n = 24), B/Victoria (n = 34), B/Yamagata (n = 11). There was no correlation between influenza (sub)type and lower RTI. Influenza infection in haematological patients is associated with significant morbidity and mortality, the risk for aggravating co‐infections, prolonged viral shedding and nosocomial transmission emphasizing the need for infection control.
A review on analytical models of brushless permanent magnet machines
Authors: Abbas A. , Iqbal A. , Lewicki Arkadiusz , Prathap B. , Mnzool M. 
Published: May 2023

AbstractThis study provides an in‐depth investigation of the use of analytical and numerical methods in analyzing electrical machines. Although numerical models such as the finite‐element method (FEM) can handle complex geometries and saturation effects, they have significant computational burdens, are time‐consuming, and are inflexible when it comes to changing machine geometries or input values. Analytical models based on magnetic equivalent circuits (MEC) or solving Maxwell's equations can be faster and more flexible, but less accurate for complex machine structures. The paper focuses on the recent development of analytical models for brushless permanent‐magnet (PM) machines that have become increasingly popular in low and medium‐power applications. The literature review covers the recent developments in analytical models for PM machines with respect to various machine quantities such as magnetic flux density components, induced voltage, inductances, electromagnetic force/torque, efficiency, or unbalanced magnetic force (UMF). It outlines the advantages and disadvantages of different analytical models such as the zero‐dimensional (0‐D), one‐dimensional (1‐D), two‐dimensional (2‐D), and three‐dimensional (3‐D) analytical methods, as well as the Maxwell and basic mathematical analysis. Although the MEC models are faster than the numerical model, they are not as accurate for various structures of electrical machines including a great magnetic air gap. They also note that the analytical models based on the Maxwell equations are faster than the numerical ones and have the potential to obtain acceptable accuracy similar to the numerical models in electrical machines. Overall, this literature review provides valuable insights for researchers and engineers in selecting appropriate analytical models for PM machines. It highlights the trade‐offs between accuracy and computational efficiency when choosing between numerical and analytical models, and the flexibility of analytical models to address changes in machine geometries or input values. Additionally, this helps researchers save time in determining appropriate references regarding the analytical models of brushless PM machines.
Direct parameter extraction method of EEHEMT nonlinear model for InP HEMT
Authors: Xu Jiahui , Zhang Ao , Gao Jianjun 
Published: June 2023

AbstractA direct parameter extraction method of EEHEMT nonlinear empirical model is proposed in this paper. An improved DC model is also presented by considering the channel length modulation parameter () as a function of gate‐to‐source voltage. Model verification is carried out by comparison of measured and simulated current–voltage characteristics and S‐parameters. Good agreement is obtained between the measured and modeled results for 2 × 15 μm gatewidth (number of gate fingers × gatewidth) 70‐nm gatelength InP high electron mobility transistors (HEMT). An increased accuracy in modeling the I–V and RF characteristics is also obtained in the proposed model, compared with the conventional one.
Raman spectroscopy investigations of the Martian regolith breccia Northwest Africa 7533: A support to in situ Raman spectroscopy on Mars
Authors: Malarewicz Virgile , Beyssac Olivier , Zanda Brigitte , Hewins Roger , Pont Sylvain , Bouley Sylvain , Bernard Sylvain , Gauthier Michel , Morand Marc , Garino Yiuri , Rosier Philippe 
Published: June 2023

AbstractUsing continuous‐wave and time‐resolved Raman spectroscopy, we investigate and characterize the mineralogy of the NWA 7533 meteorite, a unique Martian regolith breccia. This meteorite is a crucial sample, giving a rare access to the formation and evolution of the primitive Martian crust, with crystallization processes beginning up to ~4.4 Ga years ago. We provide an overview of Raman spectra for feldspar, plagioclase, pyroxene, olivine, apatite, merrillite, zircon, pyrite, and various Fe‐Cr‐Ti oxides like magnetite, hematite, ilmenite, and rutile. Most analytical points are paired with previous electron microprobe analyses for deeper interpretation of Raman data. The variability of the silicate minerals composition obtained through microanalysis is traced through variation of the Raman spectra characteristics. No trace of any shock event is observed in the mineral structures. Structural diversity of zircon is linked to various metamictization stages. The luminescence signal of minerals bearing rare earth elements (REE), mainly phosphate and zircon, is documented in detail and discussed. We discuss the presence of at least two generations of phosphate minerals with implications for magmatic petrology. Because NWA 7533 provides a unique sampling of various crustal lithologies of Mars, this spectral dataset could be a reference for Raman instruments presently working on Mars (e.g., NASA Mars2020 Perseverance) or going to this planet or its moon Phobos in the future (e.g., ESA ExoMars, JAXA MMX).
Founder involvement in CEO turnover
Authors: Kowalewski Oskar , Majda‐Kariozen Aleksandra , Socha Błażej 
Published: May 2023

AbstractWe study the role of a company founder in the internal governance of firms. Using a sample of 484 CEO turnovers for 2000–2015, we establish that CEOs are fired for poor performance. However, the likelihood of a poor‐performing founder‐CEO being fired is lower than that of an outsider CEO. Moreover, having a founder as a member of the executive or supervisory board decreases the likelihood that a CEO will be dismissed for poor performance. Similarly, founder ownership may have the same effect on CEO turnover. Finally, being a founder does not guarantee a poor‐performing CEO a chairman position after being fired.
Separation and identification of different therapeutic pharmaceutical drugs on humic acid‐based HPLC column: Method optimization using central composite design
Authors: Ayyildiz Hamide Filiz , Memon Fakhar N. , Mangi Irfan Ali , Kara Huseyin 
Published: May 2023

Multimode chromatographic separations are highly desirable in pharmaceutical and environmental sciences. Current study deals with the application of newly developed mixed‐mode end capped‐immobilized humic acid onto an aminopropyl silica based chromatographic column for separation and identification of six drugs belonging to different therapeutic groups for its applicability in pharmaceutical industries. For this, central composite design was used to evaluate the separation and resolution by optimization of three most effective parameters (acetonitrile%, flow rate, and pH of mobile phase). Second‐order quadratic model was used to evaluate their effect on resolution of peaks; the probability value (<0.05) obtained from analysis of variance suggested the best applicability of the model. Desirability function was applied to calculate optimum conditions (44.8% acetonitrile, 1.75 mL/min of flow rate, and 7.5 pH) required to achieve maximum separation with good resolution within 11 min. The method was validated for linearity, precision accuracy, selectivity, and sensitivity. The results revealed a highly precise (coefficient of variance > 1%), linear (R2 = 0.99), and highly selective method. Moreover, the limit of detection/quantification values revealed acceptable sensitivity of the method. The developed column was compared for its efficiency with a commercially available column and found to be highly applicable for industrial applications.
Outcomes of Short‐Term Surgical Trips in Otolaryngology—Head and Neck Surgery: A Scoping Review
Authors: Wiedermann Josh , Douse Dontre' M. , Green Katerina J. , Pang Jonathan C. , Blount Quinton , Yu Karina , Shrime Mark 
Published: May 2023

ObjectiveThis scoping review aims to explore the current body of literature to characterize how short‐term surgical trips (STSTs) in Otolaryngology‐Head and Neck Surgery (OtoHNS) contribute to surgical, educational, and sustainability‐based outcomes in low‐ and middle‐income countries (LMICs). We aim to use these data to synthesize aspects of STSTs that are successful with the hopes of shaping future global efforts.Data SourcesData sources included Ovid MEDLINE, Ovid Embase, Ovid Cochrane Central Register of Controlled Trials, Ovid Cochrane Database of Systematic Reviews, and Scopus.Review MethodsA comprehensive search was conducted on several databases from inception to October 14, 2021. We included primary studies exploring any surgical or educational outcomes of global short‐term surgical endeavors within LMICs. Data were then extracted to evaluate the heterogenous body of literature that exists, characterizing the surgical, educational, and sustainability‐based outcomes.ResultsForty‐Seven studies were included in the final analysis. Most publications were focused on surgical interventions (39 of 47; 82.9%); 13 (27.7%) studies included education as the primary aim and 12 (25.5%) considered sustainability a significant aim. Of the 94 first and last authors, there were zero first authors and only one last author with an LMIC affiliation. Twenty‐six studies (55%) mentioned that any patients were seen in follow‐up, ranging from one day to five years.ConclusionOur scoping review demonstrates that most STSTs have focused primarily on surgical procedures with a lack of appropriate long‐term follow‐up. However, the available outcome‐based information presented helps identify factors that characterize a strong short‐term global surgical program.Level of EvidenceNA Laryngoscope, 134:32–39, 2024