bluuebunny/crossref_metadata_2025_split huggingface dataset:
Butyryl/Caproyl-CoA:Acetate CoA-transferase: cloning, expression and characterization of the key enzyme involved in medium-chain fatty acid biosynthesis
Authors: Yang Qingzhuoma , Guo Shengtao , Lu Qi , Tao Yong , Zheng Decong , Zhou Qinmao , Liu Jun 
Published: August 2021

Abstract
Coenzyme A transferases (CoATs) are important enzymes involved in carbon chain elongation, contributing to medium-chain fatty acid (MCFA) biosynthesis. For example, butyryl-CoA:acetate CoA transferase (BCoAT) is responsible for the final step of butyrate synthesis from butyryl-CoA. However, little is known about caproyl-CoA:acetate CoA-transferase (CCoAT), which is responsible for the final step of caproate synthesis from caproyl-CoA. In the present study, two CoAT genes from Ruminococcaceae bacterium CPB6 and Clostridium tyrobutyricum BEY8 were identified by gene cloning and expression analysis. Enzyme assays and kinetic studies were carried out using butyryl-CoA or caproyl-CoA as the substrate. CPB6-CoAT can catalyze the conversion of both butyryl-CoA into butyrate and caproyl-CoA into caproate, but its catalytic efficiency with caproyl-CoA as the substrate was 3.8-times higher than that with butyryl-CoA. In contrast, BEY8-CoAT had only BCoAT activity, not CCoAT activity. This demonstrated the existence of a specific CCoAT involved in chain elongation via the reverse β-oxidation pathway. Comparative bioinformatics analysis showed the presence of a highly conserved motif (GGQXDFXXGAXX) in CoATs, which is predicted to be the active center. Single point mutations in the conserved motif of CPB6-CoAT (Asp346 and Ala351) led to marked decreases in the activity for butyryl-CoA and caproyl-CoA, indicating that the conserved motif is the active center of CPB6-CoAT and that Asp346 and Ala351 have a significant impact on the enzymatic activity. This work provides insight into the function of CCoAT in caproic acid biosynthesis and improves understanding of the chain elongation pathway for MCFA production.
Role of ACE2 in pregnancy and potential implications for COVID-19 susceptibility
Authors: Azinheira Nobrega Cruz Nayara , Stoll Danielle , Casarini Dulce Elena , Bertagnolli Mariane 
Published: August 2021

Abstract
In times of coronavirus disease 2019 (COVID-19), the impact of severe acute respiratory syndrome (SARS)-coronavirus (CoV)-2 infection on pregnancy is still unclear. The presence of angiotensin-converting enzyme (ACE) 2 (ACE2), the main receptor for SARS-CoV-2, in human placentas indicates that this organ can be vulnerable for viral infection during pregnancy. However, for this to happen, additional molecular processes are critical to allow viral entry in cells, its replication and disease manifestation, particularly in the placenta and/or feto–maternal circulation. Beyond the risk of vertical transmission, COVID-19 is also proposed to deplete ACE2 protein and its biological actions in the placenta. It is postulated that such effects may impair essential processes during placentation and maternal hemodynamic adaptations in COVID-19 pregnancy, features also observed in several disorders of pregnancy. This review gathers information indicating risks and protective features related to ACE2 changes in COVID-19 pregnancies. First, we describe the mechanisms of SARS-CoV-2 infection having ACE2 as a main entry door and current evidence of viral infection in the placenta. Further, we discuss the central role of ACE2 in physiological systems such as the renin–angiotensin system (RAS) and the kallikrein–kinin system (KKS), both active during placentation and hemodynamic adaptations of pregnancy. Significant knowledge gaps are also identified and should be urgently filled to better understand the fate of ACE2 in COVID-19 pregnancies and the potential associated risks. Emerging knowledge will be able to improve the early stratification of high-risk pregnancies with COVID-19 exposure as well as to guide better management and follow-up of these mothers and their children.
Anti-inflammatory cytokine-eluting collagen hydrogel reduces the host immune response to dopaminergic cell transplants in a rat model of Parkinson’s disease
Authors: Cabré Sílvia , Alamilla Verónica , Moriarty Niamh , Pandit Abhay , Dowd Eilís 
Published: August 2021

Abstract
In cell replacement approaches for Parkinson’s disease, the intracerebral implantation of dopamine neuron-rich grafts generates a neuroinflammatory response to the grafted cells that contributes to its varied outcome. Thus, the aim of the present study was to fabricate an anti-inflammatory cytokine-eluting collagen hydrogel capable of delivering interleukin (IL)-10 to the brain for reduction of the neuroinflammatory response to intracerebral cellular grafts. In vitro assessment revealed that cross-linker concentration affected the microstructure and gelation kinetics of the hydrogels and their IL-10 elution kinetics, but not their cytocompatibility or the functionality of the eluted IL-10. In vivo evaluation revealed that the hydrogels were capable of delivering and retaining IL-10 in the rat striatum, and reducing the neuroinflammatory (microglial) response to hydrogel-encapsulated grafts. In conclusion, IL-10-eluting collagen hydrogels may have beneficial anti-inflammatory effects in the context of cellular brain repair therapies for Parkinson’s disease and should be investigated further.
Minimum error entropy criterion‐based randomised autoencoder
Authors: Ma Rongzhi , Wang Tianlei , Cao Jiuwen , Dong Fang 
Published: August 2021

AbstractThe extreme learning machine‐based autoencoder (ELM‐AE) has attracted a lot of attention due to its fast learning speed and promising representation capability. However, the existing ELM‐AE algorithms only reconstruct the original input and generally ignore the probability distribution of the data. The minimum error entropy (MEE), as an optimal criterion considering the distribution statistics of the data, is robust in handling non‐linear systems and non‐Gaussian noises. The MEE is equivalent to the minimisation of the Kullback–Leibaler divergence. Inspired by these advantages, a novel randomised AE is proposed by adopting the MEE criterion as the loss function in the ELM‐AE (in short, the MEE‐RAE) in this study. Instead of solving the output weight by the Moore–Penrose generalised inverse, the optimal output weight is obtained by the fixed‐point iteration method. Further, a quantised MEE (QMEE) is applied to reduce the computational complexity of. Simulations have shown that the QMEE‐RAE not only achieves superior generalisation performance but is also more robust to non‐Gaussian noises than the ELM‐AE.
A hybrid level shifted carrier‐based PWM technique for modular multilevel converters
Authors: M Aswini Kumar , Gopi Anjana K. , Biswas Jayanta , Barai Mukti 
Published: August 2021

AbstractThis paper presents a hybrid level shifted carrier‐based pulse width modulation (HLSC‐PWM) technique for modular multilevel converters (MMCs). The concept of the proposed HLSC‐PWM method is developed by combining the principles of phase disposition PWM (PD‐PWM), phase opposition disposition PWM (POD‐PWM), and alternate phase opposition disposition PWM (APOD‐PWM) methods. The main aim of the proposed HLSC‐PWM method is to generate an output voltage with half‐wave and quarter‐wave symmetries. The generated symmetrical PWM output voltage based on the proposed HLSC‐PWM method provides less total harmonic distortion (THD) and enhances the DC‐Link voltage utilization (DCLVU). A generalized mathematical model is formulated to develop a single HLSC for MMC with an N number of submodules (SMs) per arm. Theoretical analysis of DCLVU for the proposed method is described. The functionality and performance of the HLSC‐PWM method are carried out on a three‐phase five‐level MMC in MATLAB/Simulink. A hardware prototype of a single‐phase five‐level MMC is designed for experimental validation. The proposed HLSC‐PWM method is implemented on an Altera/Cyclone I series (EP1C12Q240C8N) field‐programmable gate array (FPGA), simulation and experimental results are presented.
Study of different performance measures and their relations in satellite‐based and terrestrial quantum communication
Authors: Mukhopadhyay Avik , Kumar Borah Shantom , Sharma Yashkalp , Bitragunta Sainath , Chamola Vinay 
Published: August 2021

AbstractRapid developments in quantum communication are paving the way forward for more advanced technologies. Conventional channels like optical fibres have been a great resource in recent decades. However, they suffer largely from exponential transmissivity decays and are not suitable for very long‐distance communication. Satellite links along with quantum cryptography can be the foundation of modern quantum communication systems. This work presents an overview of the hybrid quantum repeater with a detailed analysis of different parametric relations in satellite‐based communication from experimental data. The link efficiency between the satellite‐based scheme and terrestrial scheme is also compared, emphasising the satellite‐based scheme's importance for quantum communication. Finally, we present a performance analysis of different quantities and derive relations between them.
Molecular gas and star formation within 12 strong galactic bars observed with IRAM-30 m
Authors: Díaz-García S. , Lisenfeld U. , Pérez I. , Zurita A. , Verley S. , Combes F. , Espada D. , Leon S. , Martínez-Badenes V. , Sabater J. , Verdes-Montenegro L. 
Published: August 2021

Context.While some galactic bars show recent massive star formation (SF) along them, some others do not. Whether bars with low level of SF are a consequence of low star formation efficiency, low gas inflow rate, or dynamical effects remains a matter of debate.Aims.In order to study the physical conditions that enable or prevent SF, we perform a multi-wavelength analysis of 12 strongly barred galaxies with total stellar masses log10(M⋆/M⊙)∈[10.2, 11], chosen to host different degrees of SF along the bar major axis without any prior condition on gas content. We observe the CO(1–0) and CO(2–1) emission within bars with the IRAM-30 m telescope (beam sizes of 1.7–3.9 kpc and 0.9–2.0 kpc, respectively; 7–8 pointings per galaxy on average).Methods.We estimated molecular gas masses (Mmol) from the CO(1–0) and CO(2–1) emissions. SF rates (SFRs) were calculated from GALEX near-ultraviolet (UV) and WISE 12 μm images within the beam-pointings, covering the full bar extent (SFRs were also derived from far-UV and 22 μm).Results.We detect molecular gas along the bars of all probed galaxies. Molecular gas and SFR surface densities span the ranges log10(Σmol/[M⊙pc−2]) ∈ [0.4,2.4] and log10(ΣSFR/[M⊙pc−1kpc−2]]) ∈ [−3.25, −0.75], respectively. The star formation efficiency (SFE; i.e., SFR/Mmol) in bars varies between galaxies by up to an order of magnitude (SFE ∈[0.1, 1.8] Gyr−1). On average, SFEs are roughly constant along bars. SFEs are not significantly different from the mean value in spiral galaxies reported in the literature (∼0.43 Gyr−1), regardless of whether we estimateMmolfrom CO(1–0) or CO(2–1). Interestingly, the higher the total stellar mass of the host galaxy, the lower the SFE within their bars. In particular, the two galaxies in our sample with the lowest SFE and ΣSFR(NGC 4548 and NGC 5850, SFE ≲ 0.25 Gyr−1, ΣSFR ≲ 10−2.25 M⊙yr−1kpc−2,M⋆ ≳ 1010.7 M⊙) are also those hosting massive bulges and signs of past interactions with nearby companions.Conclusions.We present a statistical analysis of the SFE in bars for a sample of 12 galaxies. The SFE in strong bars is not systematically inhibited (either in the central, middle, or end parts of the bar). Both environmental and internal quenching are likely responsible for the lowest SFEs reported in this work.
Bound mass of Dehnen models with a centrally peaked star formation efficiency
Authors: Shukirgaliyev B. , Otebay A. , Sobolenko M. , Ishchenko M. , Borodina O. , Panamarev T. , Myrzakul S. , Kalambay M. , Naurzbayeva A. , Abdikamalov E. , Polyachenko E. , Banerjee S. , Berczik P. , Spurzem R. , Just A. 
Published: August 2021

Context. Understanding the formation of bound star clusters with a low star formation efficiency (SFE) is important for improving our knowledge of the star-formation history of galaxies. In N-body models of star-cluster evolution after gas expulsion, the Plummer model with an outer power law density profile has been used in a broad range of studies.
Aims. Here, we study the impact of the density profile slopes on the survivability of the low-SFE star clusters after instantaneous gas expulsion. We compare cases when a stellar cluster exhibits a Plummer profile to those with Dehnen profiles, including cuspy ones of different slopes at the time of formation.
Methods. We determined the corresponding density profile of the residual gas for a given global SFE, assuming that our model clusters formed with a constant efficiency per free-fall time and, hence, with a shallower density profile for the gas than that of the stars. We performed direct N-body simulations of evolution of clusters initially in virial equilibrium within the gas potential following gas removal.
Results. We find that the violent relaxation lasts no longer than 20 Myr, independently of the density profile power law slopes. Dehnen model clusters survive after violent relaxation with significantly lower SFEs when the global SFE measured within the Jacobi radius or within a half-mass radius. Dehnen γ = 0 model clusters show a similar final bound fraction with the Plummer model clusters if the global SFE is measured within ten scale radii. The final bound fraction increases with the γ values for a given global SFE.
Conclusions. We conclude that Dehnen clusters better resist the consequences of the violent relaxation that follows the instantaneous gas expulsion, as compared to the Plummer clusters. Therefore, the shallower the outer density slope of the low-SFE clusters, the better their prospects for survival after gas expulsion. Among the Dehnen clusters, we find that the steeper the inner slope, the higher the bound mass fraction that is retained, following the violent relaxation for a given global SFE.
Tele-Audiology: Ready or Not
Authors: Palmer Catherine V. 
Published: August 2021

AbstractThe use of various forms of tele-audiology exploded during the pandemic. This brief article provides tips and considerations for providing tele-audiology as we move beyond the pandemic. Importantly, audiologists need to document all forms of remote care including audio/visual, telephone (audio only), and email to support movement toward state licensing boards acknowledging that audiologists are qualified to provide this care and for insurers to support reimbursement for care provided via this mechanism. Educators will need to ensure that classroom and clinical education includes tele-audiology.
Polarized we trade? Intraparty polarization and US trade policy
Authors: Friedrichs Gordon M. 
Published: August 2021

AbstractResearch indicates that polarization has led to an increasing dispersion between moderate and more extreme voters within both parties. Intraparty polarization supposedly affects the nature of interparty competition as it creates political space for new political realignments and the rise of anti-establishment candidates. This article examines the extent and impact of intraparty polarization in Congress on US trade policy. Specifically, the article examines whether (and which) trade policy preferences are distributed within and between both parties, as well as how intraparty polarization has influenced the outcome of US trade negotiations. It is theorized that intraparty polarization causes crosscutting legislative coalitions around specific trade policies and political realignments around ideological factions, with consequences for the outcome of trade negotiations. By relying on a unique dataset of congressional letters and co-sponsorship legislation, the article first derives trade policy preferences from members of Congress and computes their ideological means. Two contemporary cases of US trade policy are examined: The Transpacific Partnership Agreement and the US–Mexico–Canada Agreement. Via a structured-focused comparison of both cases, the paper finally assesses under which combinations of preference-based and ideology-based intraparty polarization Congress manages to ratify trade agreements. Findings suggest that both parties are intrinsically polarized between free trade and fair trade preferences yet show variance in their degree of ideology-based intraparty polarization. These findings contribute to existing work on bipartisanship as well as factions in the foreign policy realm, as it shows under which circumstances legislators can build crosscutting coalitions around foreign policies.
Homodyne interferometry using a phase rotator for calibration of sine–cosine phase detection of a 70 GHz probe beam through a plasma
Authors: Nozawa Y. , Uchida M. , Igami H. , Kajita R. , Tanaka H. , Maekawa T. 
Published: August 2021

Homodyne interferometry using a motorized phase rotator for calibration of sine–cosine detection of the phase shift of a 70 GHz probe beam through a plasma has been developed. Four interferometers based on this interferometry have been installed on the low aspect ratio torus experiment (LATE) device with four horizontal probe beams on the mid-plane, which has measured the line-integrated electron densities with a time resolution of 10 μs and a resolution of line-integrated density of 5 × 1015 m−2.
Volatile chemical product emissions enhance ozone and modulate urban chemistry
Authors: Coggon Matthew M. , Gkatzelis Georgios I. , McDonald Brian C. , Gilman Jessica B. , Schwantes Rebecca H. , Abuhassan Nader , Aikin Kenneth C. , Arend Mark F. , Berkoff Timothy A. , Brown Steven S. , Campos Teresa L. , Dickerson Russell R. , Gronoff Guillaume , Hurley James F. , Isaacman-VanWertz Gabriel , Koss Abigail R. , Li Meng , McKeen Stuart A. , Moshary Fred , Peischl Jeff , Pospisilova Veronika , Ren Xinrong , Wilson Anna , Wu Yonghua , Trainer Michael , Warneke Carsten 
Published: August 2021

SignificanceRecent work in Los Angeles has shown that urban volatile organic compound (VOC) emissions from consumer and industrial products—termed volatile chemical products (VCPs)—are now an important source of ozone precursors. Using advancements in VOC instrumentation, we show that VCP emissions are ubiquitous in urban regions and can be identified via unique VOC fingerprints. Through detailed modeling, we show that VCPs are as important to ozone production as fossil fuel VOCs and that the chemistry of VCPs can have significant impacts on model simulations of key atmospheric processes. Consequently, air quality models must be updated to account for both the emissions and atmospheric chemistry of VCPs in order to capture their full impact on urban air quality.
Footprint of greenhouse forcing in daily temperature variability
Authors: Kotz Maximilian , Wenz Leonie , Levermann Anders 
Published: August 2021

Significance
Understanding how the variability of daily temperature may change with greenhouse gas emissions is important because it has been identified as a key factor in societal and economic well-being. Assessing historical changes to daily temperature variability in comparison with those from state-of-the-art climate models, we show that variability has changed with distinct global patterns over the past 65 years, changes which are attributable to rising concentrations of greenhouse gases. If these rises continue, temperature variability is projected to increase by up to 100% at low latitudes and decrease by 40% at northern high latitudes by the end of the century. We further show that these changes would be limited by mitigating emissions and will depend on the equilibrium climate sensitivity.
On conceptualizing grammatical change in a Darwinian framework
Authors: Breyl Michael , Leiss Elisabeth 
Published: August 2021

Abstract
Approaching language change within a Darwinian framework constitutes a long-standing tradition within the
literature of diachronic linguistics. However, many publications remain vague, omitting conceptual details or missing necessary
terminology. For example, phylogenetic trees of language families are regularly compared to biological speciation, but definitions
on mechanisms of inheritance, i.e. how linguistic information is transferred between individuals and cohorts, or on the linguistic
correlates to genotype and phenotype are often missing or lacking. In light of this, Haider’s attempts to develop this
approach into a theoretically more precise position, closely mirroring principles of Darwinian natural selection in the dimension
of diachronic grammatical change, but contrasting this with non-Darwinian lexical change. He draws a comparison to viral
replication, essentially positing that grammar variants act as mental viruses, competing for replication in new hosts, i.e.
children during critical periods of language acquisition. Haider proposes that in light of this competition for replication, the
unconscious fixation of an individual’s grammar leads to diachronic grammatical change largely mirroring Darwinian natural
selection. Despite the intuitive appeal this mode of reasoning may feature, the following response paper identifies and discusses
a suit of shortcomings to this conceptualization. Some problems arise from underspecified theoretical notions, others due to the
incomplete or inaccurate adoption of biological principles, and yet more through a partial incompatibility with empirical data.
These criticisms do not amount to a dismissal of the Darwinian framework Haider is following, but to a rejection of Haider’s
current position. Albeit it remains unclear if a truly Darwinian approach to language change can be reached, suggestions on how
Haider’s theoretical notions could be further developed are made and pertinent efforts may ultimately lead to a productive
theory.
Janus-faced presidents: extroverted and introverted politics in oil-age Niger
Authors: Schritt Jannik 
Published: August 2021

ABSTRACT
This article analyses political speeches and practices of three Nigerien presidents between 2008 and 2011. It argues that politics in Niger are characterised by a logic of code-switching between an extroverted rhetoric to gain access to international aid, and an introverted rhetoric that critiques this very international system. This analysis makes a case for studies of African states that do not completely adhere to a perspective of either neocolonial dependency or neopatrimonialism. Rather, as leaders of a Janus-faced state, Nigerien presidents walk a tightrope to manoeuvre between external and internal demands in order to acquire resources and legitimacy in both spheres.