bluuebunny/crossref_metadata_2025 huggingface dataset:
Fast unconditional initialization for superconducting qubit and resonator using quantum-circuit refrigerator
Authors: Yoshioka T. , Tsai J. S.
Published: September 2021

In a quantum computation scheme, such as recycling a qubit, the initialization of the qubit is always required. At present, the initialization of the qubit is one of the bottlenecks in such computation, and high fidelity and fast initialization still remain important research subjects. In this study, by coupling a SINIS (superconductor–insulator–normal metal–insulator–superconductor) junction to a coupled system consisting of a qubit and a resonator, a photon is removed from the resonator by single-photon-assisted tunneling, and the effective relaxation rate of the resonator is increased. In addition, by applying an |e,0⟩−|f,0⟩ drive pulse and an |f,0⟩−|g,1⟩ drive pulse to the qubit, the energy of the qubit is rapidly transferred to the resonator to realize high-speed initialization. The present simulation shows that the qubit can be initialized with 99% fidelity in 80 ns and 99.9% in 137 ns when the electron temperature of the normal metal of the SINIS junction is 10 mK. The simulation also shows that the relaxation time of the qubit is about 13% longer when the resonator is interposed between the SINIS junction and the qubit than when the SINIS junction is directly coupled to the qubit.
Three-point I–V spectroscopy deconvolves region-specific degradations in LDMOS transistors
Authors: Chen Yen-Pu , Mahajan Bikram K. , Varghese Dhanoop , Krishnan Srikanth , Reddy Vijay , Alam Muhammad A.
Published: September 2021

Unlike traditional logic transistors, hot carrier degradation (HCD) in power transistors involves simultaneous and potentially correlated degradation in multiple regions. One must deconvolve and characterize the voltage- and temperature-dependence of these region-specific degradations to develop a predictive HCD model of power transistors. Unfortunately, power transistors' doping and geometrical complexities make it challenging to use traditional defect-profiling techniques, such as charge-pumping or gated-diode methods. This Letter uses a physics-based tandem-FET model of an Laterally Diffused MOS (LDMOS) transistor to develop a “three-point I–V spectroscopy” technique that uses the time-evolution of three critical points of the measured I–V characteristics to extract mobility and threshold voltage degradations in the channel and drift regions. This innovative approach should generalize to other configurations of the LDMOS transistor as well.
Self-organization of whole-gene expression through coordinated chromatin structural transition
Authors: Zimatore Giovanna , Tsuchiya Masa , Hashimoto Midori , Kasperski Andrzej , Giuliani Alessandro
Published: September 2021

The human DNA molecule is a 2–m-long polymer collapsed into the micrometer space of the cell nucleus. This simple consideration rules out any “Maxwell demon”-like explanation of regulation in which a single regulatory molecule (e.g., a transcription factor) finds autonomously its way to the particular target gene whose expression must be repressed or enhanced. A gene-by-gene regulation is still more contrasting with the physical reality when in the presence of cell state transitions involving the contemporary expression change of thousands of genes. This state of affair asks for a statistical mechanics inspired approach where specificity arises from a selective unfolding of chromatin driving the rewiring of gene expression pattern. The arising of “expression waves” marking state transitions related to chromatin structural reorganization through self-organized critical control of whole-genome expression will be described in the present paper. We adopt as a model system the gene expression time course of a cancer cell (MCF-7) population exposed to an efficient stimulus causing a state transition in comparison with an ineffective stimulus. The obtained results will be put into the perspective of biological adaptive systems living on the edge of chaos.
Ultrahigh-rectification near-field radiative thermal diode using infrared-transparent film backsided phase-transition metasurface
Authors: Liu Yang , Tian Yanpei , Chen Fangqi , Caratenuto Andrew , Liu Xiaojie , Antezza Mauro , Zheng Yi
Published: September 2021

We present a theoretical study of near-field radiative thermal rectification combining phase-transition and high-infrared-transmittance materials. The phase-transition material vanadium dioxide (VO2), with a metal–insulator transition near 341 K, is utilized under a reasonable temperature. Four types of high-infrared-transmittance materials, including potassium bromide, sodium chloride, polyethylene, and magnesium fluoride, are introduced as thin film substrates under a VO2 grating on one side of the near-field rectifier. We explore the effects of various high-infrared-transmittance thin-film substrates and relevant geometric parameters on the thermal rectification of the device. The results show that thermal rectification can be greatly enhanced by using a one-dimensional VO2 grating backed with a high-infrared-transmittance thin-film substrate. With the introduction of a high-infrared-transmittance substrate, the rectification ratio is dramatically boosted due to the enhancement of the substrate transmittance. This work predicts a remarkable rectification ratio as high as 161—greater than the recently reported peak values for comparable near-field radiative thermal rectification. The results outlined herein will shed light on the rapidly expanding fields of nanoscale thermal harvesting, conversion, and management.
Single carbon fiber transverse electrical resistivity measurement via the van der Pauw method
Authors: Matsuo Satoshi , Sottos Nancy R.
Published: September 2021

Although the electrical properties of carbon fibers and carbon fiber composites are critical to the design of composite materials, a direct measurement of the transverse electrical resistivity of a single carbon fiber has not yet been reported. Significant challenges arise in fabricating specimens and making electrical resistance measurements due to the geometry and small diameter of a single carbon fiber (about 4–7 μm). In this study, we report a specimen design and fabrication technique for measuring the transverse electrical resistance of an individual carbon fiber by the van der Pauw method. IM7 carbon fiber specimens are fabricated by a combination of photolithography and the focused ion beam. Specimen thickness, which is required for resistivity calculations, is measured by atomic force microscopy. We measure mean transverse electrical resistivity of (9.3 ± 0.3) × 10−5 Ω m, which is roughly six times greater than the reported longitudinal values. Our measurement technique can be applied to a range of conductive fibers. More accurate measurements of the electrical conduction in carbon fibers are critical for applications such as electromagnetic interference shielding, structural health monitoring, and lightning strike protection.
Differentiation of ultraviolet/visible photons from near infrared photons by MoS2/GaN/Si-based photodetector
Authors: Singh Deependra Kumar , Pant Rohit Kumar , Nanda K. K. , Krupanidhi S. B.
Published: September 2021

Conventional photodetectors (PDs) generally exhibit a unipolar photoresponse within their responsive spectral range. Different from the traditional PDs, we report here a broadband PD based on the MoS2/GaN/Si heterojunction that shows a unique phenomenon of wavelength selectivity through photocurrent polarity inversion. Overall, the device can differentiate the photons of the ultraviolet (UV)/visible region from that of the near infrared (NIR) region. This polarity inversion is explained with the help of the band diagram and the wavelength dependent photothermoelectric (PTE) effect in MoS2. The vertical transport characteristics of the MoS2/GaN/Si device exhibit a high spectral response in a broad range of wavelengths (300–1100 nm) in a self-biased mode. The maximum response of the device is found to be 23.81 A/W at a wavelength of 995 nm. Our results demonstrate a route for the development of PDs without filter that possess a lot of potential for the futuristic photonic devices.
Vibronic dynamics resolved by global and target analysis of ultrafast transient absorption spectra
Authors: van Stokkum Ivo H. M. , Kloz Miroslav , Polli Dario , Viola Daniele , Weißenborn Jörn , Peerbooms Ebo , Cerullo Giulio , Kennis John T. M.
Published: September 2021

We present a methodology that provides a complete parametric description of the time evolution of the electronically and vibrationally excited states as detected by ultrafast transient absorption (TA). Differently from previous approaches, which started fitting the data after ≈100 fs, no data are left out in our methodology, and the “coherent artifact” and the instrument response function are fully taken into account. In case studies, the method is applied to solvents, the dye Nile blue, and all-trans β-carotene in cyclohexane solution. The estimated Damped Oscillation Associated Spectra (DOAS) and phases express the most important vibrational frequencies present in the molecular system. By global fit alone of the experimental data, it is difficult to interpret in detail the underlying dynamics. Since it is unfeasible to directly fit the data by a theoretical simulation, our enhanced DOAS methodology thus provides a useful “middle ground” where the theoretical description and the fit of the experimental data can meet. β-carotene in cyclohexane was complementarily studied with femtosecond stimulated Raman spectroscopy (FSRS). The fs–ps dynamics of β-carotene in cyclohexane in TA and FSRS experiments can be described by a sequential scheme S2 → hot S1 → S1′ → S1 → S0 with lifetimes of 167 fs (fixed), 0.35, 1.1, and 9.6 ps. The correspondence of DOAS decaying concomitantly with hot S1 and the Species Associated Difference Spectra of hot S1 in TA and FSRS suggest that we observe here features of the vibrational relaxation and nuclear reorganization responsible for the hot S1 to S1 transition.
Predicted metallization of hydrogen nanograins at low pressures
Authors: Lei Haile , Li Xibo , Lin Wei , Wang Kai
Published: September 2021

A single hydrogen nanograin has been modeled here to explore the evolution of its structural properties under compression. It is revealed to change from the molecular-insulator (P63/mmc) to the molecular-metal phase (Pca21) in the form of the hollow spherical shell at a pressure much lower than the one for metallization of bulk hydrogen. The compression is demonstrated to induce both the structure transition and the charge transfer between atoms so that the infrared bands are determined both by the structure and by the atomic-charge distribution. The hydrogen nanograins are, thus, proposed to change more easily from the insulator to metallic hydrogen with respect to bulk hydrogen. Our findings open an alternative route to creating metallic hydrogen.
Recommended Correlations for the Surface Tension of 80 Esters
Authors: Mulero A. , Cachadiña I. , Vegas A.
Published: September 2021

Surface tension values for 80 esters have been compiled from databases, books, and papers in the literature. The data have been carefully screened and selected, and the final dataset for each fluid has been fitted as a function of the temperature by using the Guggenheim–Katayama model, which requires two or four adjustable coefficients for each fluid. As a result, recommended correlations are proposed for each of the 80 esters, providing mean absolute deviations below 0.55 mN/m, mean absolute percentage deviations below 2.2%, and percentage deviations below 10% except for 3 data out of 1846 selected. These correlations are added to the collection of those previously proposed for different kinds of fluids, including common fluids, alcohols, refrigerants, organic acids, and n-alkanes.
Modulating the photoresponse performance of the flexible Si/ZnO film heterojunction photodetectors by piezo-phototronic effect
Authors: Zhou Yan , Zhang Yaju , Ding Zhenyu , Zhang Yuanzheng , Ren Bingyan , Yang Liya , Wang Jiantao , Zheng Haiwu , Wang Xingfu , Wang Zhong Lin
Published: September 2021

Silicon-based photodetectors in photoelectric sensing applications are crucial. In the previous studies of the piezo-phototronic effect on performance modulation of Si/ZnO heterojunctions, the majority is based on a rigid silicon substrate and a ZnO one-dimensional nanostructure, causing incompatibility with advanced semiconductor processing technology as well as the limitation in the field of wearable application. Here, flexible p-Si/n-ZnO film heterojunction photodetectors have been constructed by sputtering ZnO films on chemically thinned Si substrates. Under 405 nm light illumination and at −0.5 V bias, the reverse photocurrent of the heterojunction under the −0.73‰ compression strain increased by 50.36% compared to that under a strain-free state, while the reverse photocurrent for the same device under 0.73‰ tensile strain decreased by 29.2% compared to that under the strain-free state. The introduction of a flexible silicon wafer realizes a bidirectional photocurrent response regulation, which lies in the fact that the strain-induced piezo-potential governs the local energy band structure at the heterojunction interface and, thus, influences the carrier transport in the heterojunction region. The COMSOL simulation results further verify the evolution of the energy band structure at the heterojunction interface at different strain states. This work provides a strategy to design silicon-based optoelectronic devices via the piezo-phototronic effect of a ZnO film.
Plasma response to resonant magnetic perturbations near rotation zero-crossing in low torque plasmas
Authors: Xie Pengcheng , Sun Youwen , Liu Yueqiang , Gu Shuai , Ma Qun , Ye Cheng , Wu Xuemin , Sheng Hui , Team EAST
Published: September 2021

The plasma response to resonant magnetic perturbations (RMPs) near the pedestal top is crucial for accessing edge localized modes (ELMs) suppression in tokamaks. Since the radial location of the rotation zero-crossing plays a key role in determining the threshold for field penetration of RMPs, the plasma response may be different in low input torque plasmas. In this work, the linear MHD code MARS-F is applied to reveal the dependence of the plasma response to RMPs on the location of the rotation zero-crossing by a scan of E × B rotation profiles based on an EAST equilibrium. It is shown that the plasma response is enhanced when the E × B rotation zero-crossing occurs near the rational surfaces. The dependence of the plasma response on the location of the E × B rotation zero-crossing is well fitted by a double Gaussian, indicating two effects in this enhancement. One is induced by a rotation screening effect shown as a wide base (with a width around 10–20 krad/s), and the other is related to a resistive singular layer effect characterized by a localized peak (with a width around 3–4 krad/s). The peak of each resonant harmonic in the plasma response appears always at the rotation zero-crossing. The width of the peak scales with the resistive singular layer width. The plasma displacement suggests that the response is tearing-like when the zero-crossing is within the singular layer, while it is kink-like when the zero-crossing is far from the layer. The reduction in the magnetic islands width is only by a factor of two, when the absolute value of the local E × B rotation increases from 0 to 10–20 krad/s. This is further confirmed in modeling of the plasma response in an EAST ELM suppression discharge. Although there is a zero-crossing in the E × B rotation but none in the electron perpendicular rotation, no significant difference in the plasma response is obtained using these two rotation profiles. This suggests that the rotation near the pedestal top should not be far away from zero but it may not be necessary to have a zero-crossing for accessing ELM suppression.
Amplification of a slipping quasi-monochromatic wave pulse by an electron flow with a wide velocity spread
Authors: Bespalov P. A. , Savilov A. V.
Published: September 2021

Cherenkov interaction between a wave pulse and a flow of electrons possessing a very wide (on the scale of the characteristic band of the resonant electron–wave interaction) velocity spread is considered. We show that if the wave pulse is short enough, and its group velocity is close to the phase velocity, then the effect of the slippage of the resonant electrons with respect to the wave pulse leads to the transformation of an inert electronic medium into an active one (absorbing or amplifying the wave pulse, depending on the slippage sign). This can be a mechanism of formation of short powerful electromagnetic pulses as a result of amplification of short-pulse weak noises by electron flows which, due to natural reasons, have a large velocity spread, namely, electron flows in the magnetosphere of planets, in the plasma envelope of brown dwarfs and neutron stars, as well as in electron masers with weak electron–wave interaction (including ultra-relativistic electron beams used in free-electron lasers).
Rotational speed sensor based on the magnetoelectric effect of composite FeSiB/Pb(Zr,Ti)O3
Authors: Jiang Xueling , Li Linfeng , Lu Caijiang , Zhu Renren , Hua Qiang , Dong Longfei , Fu Guoqiang
Published: September 2021

This paper proposes a rotational speed sensor based on the magnetoelectric coupling effect. The sensor is composed of a permanent magnet array and a magnetoelectric composite FeSiB/Pb(Zr,Ti)O3. The permanent magnet array rotates with the gear to provide a stable sinusoidal alternating magnetic field in its surrounding space, which is simulated and analyzed by using the finite element simulation software. Based on the magnetoelectric coupling effect, the composite FeSiB/Pb(Zr,Ti)O3 senses the magnetic field information and transforms it into electrical information so as to realize the rotating speed measurement. The experiments of sensing distance and linearity are carried out. The proposed sensor is compared and verified by a coil sensor. The results show that the proposed speed sensor has good linearity in the speed measured range, and the sensing distance can reach 15 mm. At the same time, it can be used for low-speed measurement. This kind of speed sensor has broad application prospects in the field of rotational speed measurement.
Early stage of delayed coalescence of soluble paired droplets: A numerical study
Authors: Chen Jun-Yuan , Gao Peng , Xia Yu-Ting , Li Er-Qiang , Liu Hao-Ran , Ding Hang
Published: September 2021

When two sessile droplets of miscible fluids come into contact, the coalescence process can be significantly delayed owing to the competition between the capillary and Marangoni effects. It is important to reveal the mechanism of the deformation and displacement of the sessile droplets at the early stage of the delayed coalescence, which determines the self-stabilized shape and joint motion of the two droplets later on. In this work, we numerically investigate the early-stage dynamics of the delayed coalescence between two sessile droplets of equal size and laden with aqueous mixtures of different solvent mass fractions. A three-dimensional numerical model is adopted based on lubrication theory and is validated by comparison against previous experimental results. Through simulation, we first showed how the concentration transport is coupled with droplet deformation. Then, we explained the underlying mechanism of delayed coalescence by analyzing the liquid bridge numerically and theoretically. A scaling law for the duration of liquid bridge growth is given and agrees well with the numerical results. Finally, the effects of the solubility on the dynamics are investigated. Our study reveals how the capillary and Marangoni effects dominate the flow during the early stage of the delayed coalesce and thus determine its following behavior.
X-ray diffraction and equation of state of the C–S–H room-temperature superconductor
Authors: Lamichhane Anmol , Kumar Ravhi , Ahart Muhtar , Salke Nilesh P. , Dasenbrock-Gammon Nathan , Snider Elliot , Meng Yue , Lavina Barbara , Chariton Stella , Prakapenka Vitali B. , Somayazulu Maddury , Dias Ranga P. , Hemley Russell J.
Published: September 2021

X-ray diffraction indicates that the structure of the recently discovered carbonaceous sulfur hydride (C–S–H) room-temperature superconductor is derived from previously established van der Waals compounds found in the H2S–H2 and CH4–H2 systems. Crystals of the superconducting phase were produced by a photochemical synthesis technique, leading to the superconducting critical temperature Tc of 288 K at 267 GPa. X-ray diffraction patterns measured from 124 to 178 GPa, within the pressure range of the superconducting phase, are consistent with an orthorhombic structure derived from the Al2Cu-type determined for (H2S)2H2 and (CH4)2H2 that differs from those predicted and observed for the S–H system at these pressures. The formation and stability of the C–S–H compound can be understood in terms of the close similarity in effective volumes of the H2S and CH4 components, and denser carbon-bearing S–H phases may form at higher pressures. The results are crucial for understanding the very high superconducting Tc found in the C–S–H system at megabar pressures.
Temperature-dependent mechanical behavior of an Al0.5Cr0.9FeNi2.5V0.2 high-entropy alloy
Authors: Zhou Shichao , Liaw Peter K. , Xue Yunfei , Zhang Yong
Published: September 2021

High-entropy alloys (HEAs) with a ductile face-centered-cubic matrix and coherent nano-precipitates (L12) are promising candidate materials for heat-resistant applications. In the present work, we systematically investigated the mechanical behavior of a wrought L12-type-strengthened HEA, Al0.5Cr0.9FeNi2.5V0.2, at elevated temperatures ranging from 500 to 900 °C. We find that the Al0.5Cr0.9FeNi2.5V0.2 HEA shows a moderate strength (∼875 MPa) as well as ductility (∼15%) at 500 °C and then a distinct ductile-to-brittle transition at 600 °C due to the brittle body-centered-cubic phase and weak deformation accommodation at grain boundaries (GBs). The further increase in temperatures up to 850 °C caused a decrease in strength but an increase in ductility owing to the occurrence of dynamic restoration. Correspondingly, kernel average misorientation maps of specimens exhibited a strain concentration along GBs and different deformation accommodation abilities under various conditions.
Achieving high spatial resolution in a large field-of-view using lensless x-ray imaging
Authors: Jiang Yi , Deng Junjing , Yao Yudong , Klug Jeffrey A. , Mashrafi Sheikh , Roehrig Christian , Preissner Curt , Marin Fabricio S. , Cai Zhonghou , Lai Barry , Vogt Stefan
Published: September 2021

X-ray ptychography, a powerful scanning lensless imaging technique, has become attractive for nondestructively imaging internal structures at nanoscale. Stage positioning overhead in conventional step-scan ptychography is one of the limiting factors on the imaging throughput. In this work, we demonstrate the use of advanced fly scan ptychography to achieve high-resolution ptychograms of modern integrated circuits on a large field-of-view at millimeter scale. By completely removing stage overheads between scan points, the imaging time for millimeter-size sample can be significantly reduced. Furthermore, we implement the orthogonal probe relaxation technique to overcome the variation of illumination across the large scan area as well as local vibrations. The capability of x-ray ptychography shown here is broadly applicable for various studies, which requires both high spatial resolution and large scan area.
Impact and outcome evaluation of HealthPathways: a scoping review of published methodologies
Authors: Senanayake Sameera , Abell Bridget , Novick Monica , Exley Helen , Dolejs Wendy , Hutchinson Kylie , McPhail Steven , Kularatna Sanjeewa
Published: September 2021

ABSTRACT INTRODUCTION The HealthPathways programme is an online health information system used mainly in primary health care to promote a consistent and integrated approach to patient care. AIM The aim of this study is to perform a scoping review of the methodologies used in published impact and outcomes evaluations of HealthPathways programmes. METHODS The review included qualitative, quantitative or mixed-methods evaluations of the impact or outcome of HealthPathways. MEDLINE, Embase, CINAHL and Web of Science databases were searched. Seven programme aims were identified in the impact and outcome evaluation: (1) increased awareness and use of HealthPathways; (2) general practitioners are supported to adopt best practice, patient-centred care; (3) increased appropriate use of resources and services; (4) improved quality of referrals; (5) enhanced consistent care and management of health conditions; (6) improved patient journeys through the local health system; and (7) reduction in health-care cost and increased value for money. RESULTS Twenty-one studies were included in the final review; 15 were research papers and six were reports. ‘Increased awareness and use of HealthPathways’ was the most frequent programme aim evaluated (n = 12). Quantitative and qualitative research methodologies, as well as prospective and retrospective data collections, have been adopted to evaluate the impact and outcome of HealthPathways. DISCUSSION Assessing the impacts and outcomes of HealthPathways may be challenging due to limitations in primary data and the interconnectedness of change across the measured aims. Each aim may therefore require specific methodologies sensitive enough to capture the impact that HealthPathways are making over time.
Considerations for early career conservation researchers seeking to engage across communities and cultures
Authors: Duggan Joe , Sokini Erame
Published: September 2021

As conservation researchers operating in the Pacific, we often seek to contribute to solutions through integrative research that involves the inclusion of different voices, knowledge systems and actors in order to build adaptive capacity and ensure system resilience. Implicit in this approach is the need for sound and effective cross-cultural communication skills in a setting where an ill-defined or inexperienced approach could do more harm than good. In this perspective essay, we draw upon the literature and our own lived experiences to offer practical advice for early career researchers (ECRs) in the area of conservation research seeking to engage across communities and cultures. This manuscript is not designed to be a definitive set of rules, but a useful resource with practical advice to help empower ECRs from the Global North to engage with communities across the Pacific.
Biodiversity in court: will the Regional Forest Agreements (RFAs) make the EPBC Act irrelevant?
Authors: Lindenmayer David , Burnett Peter
Published: September 2021

Two key pieces of Australian legislation regarding the protection of biodiversity and forest management are the federal Environment Protection and Biodiversity Conservation (EPBC) Act 1999 and the Regional Forest Agreements (RFA) Act 2002. Both have significant deficiencies. A Federal Court ruling associated with a challenge to the Victorian Government-owned logging company, VicForests, by a community environmental group (Friends of Leadbeater’s Possum Inc.) found that RFAs are exempt from the EPBC Act. There was an argument of legal interpretation concerning the exemption in the EPBC and RFA Acts relating to RFA forestry operations that are conducted ‘in accordance with’ an RFA. The Court held that ‘in accordance with’ only required that forestry operations be ‘conducted under’ an RFA rather than ‘in compliance’ with it. Therefore, the mere existence of the RFA is enough to exclude the biodiversity protections of the EPBC Act, even where there are extensive breaches of codes of practice for logging operations and logging is demonstrably unsustainable in terms of its environmental impacts. This amounts to the loss of the ‘safety net’ provided by EPBC Act to protect threatened forest-dependent species. The decision in the Federal Court highlights how deficient Australia’s environmental laws are in conserving the nation’s biodiversity, especially for forest-dependent threatened species. The ruling serves to further weaken already very weak legislation. Major reforms to the EPBC Act are urgently required.
The ATP-hydrolyzing ectoenzyme E-NTPD8 attenuates colitis through modulation of P2X4 receptor–dependent metabolism in myeloid cells
Authors: Tani Haruka , Li Bo , Kusu Takashi , Okumura Ryu , Nishimura Junichi , Okuzaki Daisuke , Motooka Daisuke , Arakawa Shoya , Mori Asuka , Yoshihara Terukazu , Ogino Takayuki , Tsai Shih-Han , Furuta Yoki , Muneta Masato , Nakamura Shota , Fukusaki Eiichiro , Yamamoto Kimiko , Yagita Hideo , Kayama Hisako , Takeda Kiyoshi
Published: September 2021

Significance

Intestinal bacteria produce extracellular ATP in the lumen during their growth, which drives host immune responses. To avoid excessive immune reactions in the intestinal mucosa, luminal ATP is finely tuned. However, how the concentration of luminal ATP is controlled in the colon remains poorly understood. Here, we discovered that ATP-hydrolyzing enzyme E-NTPD8 acts as an immunomodulator in the colon.
Entpd8
deficiency led to high sensitivity to DSS-induced colitis in mice, which was due to the sustained survival of colonic neutrophils. Extracellular ATP suppressed apoptosis by inducing metabolic alteration toward glycolysis via P2X4R in neutrophils. These results reveal the mechanism preventing innate intestinal pathology through modulation of myeloid cell metabolism and may serve to identify therapeutic targets for IBD.
The LarB carboxylase/hydrolase forms a transient cysteinyl-pyridine intermediate during nickel-pincer nucleotide cofactor biosynthesis
Authors: Rankin Joel A. , Chatterjee Shramana , Tariq Zia , Lagishetty Satyanarayana , Desguin Benoît , Hu Jian , Hausinger Robert P.
Published: September 2021

Significance

Carboxylation of nonactivated carbon atoms in aromatic rings is of considerable synthetic importance, but these reactions typically require harsh conditions or highly reactive reagents. In this study, the mechanism of pyridinium ring carboxylation is established for LarB, an enzyme that is essential for biosynthesis of the recently discovered nickel-pincer nucleotide cofactor found in a diverse family of racemases or epimerases. Structural and mutagenesis methods were used to define a new paradigm for carboxylation of a pyridinium ring in which a cysteinyl-pyridine ring intermediate enhances the nucleophilicity of the adjacent carbon atom for reaction with carbon dioxide.
Ttc30a affects tubulin modifications in a model for ciliary chondrodysplasia with polycystic kidney disease
Authors: Getwan Maike , Hoppmann Anselm , Schlosser Pascal , Grand Kelli , Song Weiting , Diehl Rebecca , Schroda Sophie , Heeg Florian , Deutsch Konstantin , Hildebrandt Friedhelm , Lausch Ekkehart , Köttgen Anna , Lienkamp Soeren S.
Published: September 2021

Significance

Cilia are tubulin-based cellular appendages, and their dysfunction has been linked to a variety of genetic diseases. Ciliary chondrodysplasia is one such condition that can co-occur with cystic kidney disease and other organ manifestations. We modeled skeletal ciliopathies by mutating two established disease genes inXenopus tropicalisfrogs. Bioinformatic analysis identifiedttc30aas a ciliopathy network component, and targeting it replicated skeletal malformations and renal cysts as seen in patients and the amphibian models. A loss of Ttc30a affected cilia by altering posttranslational tubulin modifications. Our findings identify TTC30A/B as a component of ciliary segmentation essential for cartilage differentiation and renal tubulogenesis. These findings may lead to novel therapeutic targets in treating ciliary skeletopathies and cystic kidney disease.
IRON MAN interacts with BRUTUS to maintain iron homeostasis in
Arabidopsis
Authors: Li Yang , Lu Cheng Kai , Li Chen Yang , Lei Ri Hua , Pu Meng Na , Zhao Jun Hui , Peng Feng , Ping Hua Qian , Wang Dan , Liang Gang
Published: September 2021

Significance

bHLH105 and bHLH115, key transcription factors that positively regulate Fe homeostasis, are both ubiquitinated and degraded by BRUTUS (BTS). How plants activate bHLH105 and bHLH115 under Fe-deficient conditions remains unclear. IRON MAN peptides (IMAs) are a class of small peptides that are induced by Fe deficiency and are required for Fe homeostasis, but how they regulate Fe homeostasis is also not known. Here, we established that IMA peptides sequester BTS and promote the accumulation of bHLH105 and bHLH115, thereby activating the Fe deficiency response in
Arabidopsis
.
High-dimensional profiling reveals phenotypic heterogeneity and disease-specific alterations of granulocytes in COVID-19
Authors: Lourda Magda , Dzidic Majda , Hertwig Laura , Bergsten Helena , Palma Medina Laura M. , Sinha Indranil , Kvedaraite Egle , Chen Puran , Muvva Jagadeeswara R. , Gorin Jean-Baptiste , Cornillet Martin , Emgård Johanna , Moll Kirsten , García Marina , Maleki Kimia T. , Klingström Jonas , Michaëlsson Jakob , Flodström-Tullberg Malin , Brighenti Susanna , Buggert Marcus , Mjösberg Jenny , Malmberg Karl-Johan , Sandberg Johan K. , Henter Jan-Inge , Folkesson Elin , Gredmark-Russ Sara , Sönnerborg Anders , Eriksson Lars I. , Rooyackers Olav , Aleman Soo , Strålin Kristoffer , Ljunggren Hans-Gustaf , Björkström Niklas K. , Svensson Mattias , Ponzetta Andrea , Norrby-Teglund Anna , Chambers Benedict J. ,   Karolinska KI/K COVID-19 Study Group
Published: September 2021

Significance

Accumulating evidence shows that granulocytes are key modulators of the immune response to SARS-CoV-2 infection, and their dysregulation could significantly impact COVID-19 severity and patient recovery after virus clearance. In the present study, we identify selected immune traits in neutrophil, eosinophil, and basophil subsets associated with severity of COVID-19 and with peripheral protein profiles. Moreover, computational modeling indicates that the combined use of phenotypic data and laboratory measurements can effectively predict key clinical outcomes in COVID-19 patients. Finally, patient-matched longitudinal analysis shows phenotypic normalization of granulocyte subsets 4 mo after hospitalization. Overall, in this work, we extend the current understanding of the distinct contribution of granulocyte subsets to COVID-19 pathogenesis.
Market forces determine the distribution of a leaky function in a simple microbial community
Authors: Adkins-Jablonsky Sarah J. , Clark Colleen M. , Papoulis Spiridon E. , Kuhl Matthew D. , Morris J. Jeffrey
Published: September 2021

Significance

Natural microbial communities are often deeply interdependent despite being locked in competition over a small number of limiting resources. While there are theories about how evolution can generate these dependencies, less is known about how responsibility for different tasks is assigned in a community. Here, we show that even small differences in costs paid by a species for performing a vital but “leaky” function can lead to one species consistently evolving into the sole “helper” for the entire community. We suggest that this process is analogous to the human economic principle of comparative advantage, selecting for efficient divisions of labor in microbial marketplaces.
The
Clp1
R140H mutation alters tRNA metabolism and mRNA 3′ processing in mouse models of pontocerebellar hypoplasia
Authors: Monaghan Caitlin E. , Adamson Scott I. , Kapur Mridu , Chuang Jeffrey H. , Ackerman Susan L.
Published: September 2021

Significance

Mutation of
CLP1
causes pontocerebellar hypoplasia type 10 (PCH10), a neurodegenerative disorder associated with intellectual and motor disability. We made two mouse models of PCH10: one homozygous for the mutation found in patients and one heterozygous for this mutation and a null allele. Mutant mice had motor impairments and neurodegeneration in the spinal cord and cerebellum. Mutants also had altered tRNA metabolism; however, it is not clear whether these alterations contribute to pathogenesis. In addition, mutation of
Clp1
resulted in altered poly(A) site selection and gene expression, suggesting that the role of CLP1 in mRNA 3′ end processing could be a promising avenue for future research into the pathogenesis of PCH10.
A single mutation weakens symbiont-induced reproductive manipulation through reductions in deubiquitylation efficiency
Authors: Beckmann John F. , Van Vaerenberghe Kelley , Akwa Daniel E. , Cooper Brandon S.
Published: September 2021

Significance

Wolbachiaare maternally transmitted bacteria that infect most insects, making them the most common endosymbionts.Wolbachiaachieved this status by manipulating host reproduction. For example, manyWolbachiacause cytoplasmic incompatibility (CI) that kills uninfected embryos. In females,Wolbachiacan rescue CI, promoting their spread to high frequencies in host populations. CI strength varies in nature from weak to strong. Importantly, strong CI enablesWolbachiabiocontrol strategies in mosquito systems, which protect millions of individuals from arboviruses. However, theory predicts that natural selection does not act to preserve genes that cause CI, suggesting mutations may disrupt it. We show that a single naturally observed mutation weakens CI by reducing deubiquitylation. These discoveries help elucidate the molecular basis of symbiont-induced reproductive manipulations.
TRAIL signaling promotes entosis in colorectal cancer
Authors: Bozkurt Emir , Düssmann Heiko , Salvucci Manuela , Cavanagh Brenton L. , Van Schaeybroeck Sandra , Longley Daniel B. , Martin Seamus J. , Prehn Jochen H.M.
Published: September 2021

Entosis is a form of nonphagocytic cell-in-cell (CIC) interaction where a living cell enters into another. Tumors show evidence of entosis; however, factors controlling entosis remain to be elucidated. Here, we find that besides inducing apoptosis, TRAIL signaling is a potent activator of entosis in colon cancer cells. Initiation of both apoptosis and entosis requires TRAIL receptors DR4 and DR5; however, induction of apoptosis and entosis diverges at caspase-8 as its structural presence is sufficient for induction of entosis but not apoptosis. Although apoptosis and entosis are morphologically and biochemically distinct, knockout of Bax and Bak, or inhibition of caspases, also inhibits entotic cell death and promotes survival and release of inner cells. Analysis of colorectal cancer tumors reveals a significant association between TRAIL signaling and CIC structures. Finally, the presence of CIC structures in the invasive front regions of colorectal tumors shows a strong correlation with adverse patient prognosis.
The hypervariable region of atlastin-1 is a site for intrinsic and extrinsic regulation
Authors: Kelly Carolyn M. , Byrnes Laura J. , Neela Niharika , Sondermann Holger , O’Donnell John P.
Published: September 2021

Atlastin (ATL) GTPases catalyze homotypic membrane fusion of the peripheral endoplasmic reticulum (ER). GTP-hydrolysis–driven conformational changes and membrane tethering are prerequisites for proper membrane fusion. However, the molecular basis for regulation of these processes is poorly understood. Here we establish intrinsic and extrinsic modes of ATL1 regulation that involve the N-terminal hypervariable region (HVR) of ATLs. Crystal structures of ATL1 and ATL3 exhibit the HVR as a distinct, isoform-specific structural feature. Characterizing the functional role of ATL1’s HVR uncovered its positive effect on membrane tethering and on ATL1’s cellular function. The HVR is post-translationally regulated through phosphorylation-dependent modification. A kinase screen identified candidates that modify the HVR site specifically, corresponding to the modifications on ATL1 detected in cells. This work reveals how the HVR contributes to efficient and potentially regulated activity of ATLs, laying the foundation for the identification of cellular effectors of ATL-mediated membrane processes.
Implication of folate deficiency in CYP2U1 loss of function
Authors: Pujol Claire , Legrand Anne , Parodi Livia , Thomas Priscilla , Mochel Fanny , Saracino Dario , Coarelli Giulia , Croon Marijana , Popovic Milica , Valet Manon , Villain Nicolas , Elshafie Shahira , Issa Mahmoud , Zuily Stephane , Renaud Mathilde , Marelli-Tosi Cécilia , Legendre Marine , Trimouille Aurélien , Kemlin Isabelle , Mathieu Sophie , Gleeson Joseph G. , Lamari Foudil , Galatolo Daniele , Alkouri Rana , Tse Chantal , Rodriguez Diana , Ewenczyk Claire , Fellmann Florence , Kuntzer Thierry , Blond Emilie , El Hachimi Khalid H. , Darios Frédéric , Seyer Alexandre , Gazi Anastasia D. , Giavalisco Patrick , Perin Silvina , Boucher Jean-Luc , Le Corre Laurent , Santorelli Filippo M. , Goizet Cyril , Zaki Maha S. , Picaud Serge , Mourier Arnaud , Steculorum Sophie Marie , Mignot Cyril , Durr Alexandra , Trifunovic Aleksandra , Stevanin Giovanni
Published: September 2021

Hereditary spastic paraplegias are heterogeneous neurodegenerative disorders. Understanding of their pathogenic mechanisms remains sparse, and therapeutic options are lacking. We characterized a mouse model lacking the Cyp2u1 gene, loss of which is known to be involved in a complex form of these diseases in humans. We showed that this model partially recapitulated the clinical and biochemical phenotypes of patients. Using electron microscopy, lipidomic, and proteomic studies, we identified vitamin B2 as a substrate of the CYP2U1 enzyme, as well as coenzyme Q, neopterin, and IFN-α levels as putative biomarkers in mice and fluids obtained from the largest series of CYP2U1-mutated patients reported so far. We also confirmed brain calcifications as a potential biomarker in patients. Our results suggest that CYP2U1 deficiency disrupts mitochondrial function and impacts proper neurodevelopment, which could be prevented by folate supplementation in our mouse model, followed by a neurodegenerative process altering multiple neuronal and extraneuronal tissues.
Precise asymptotics on the Birkhoff sums for dynamical systems
Authors: Fang Lulu , Takahasi Hiroki , Zhang Yiwei
Published: September 2021

We establish two precise asymptotic results on the Birkhoff sums for dynamical systems. These results are parallel to that on the partial sums of independent and identically distributed random variables previously obtained by Hsu and Robbins, Erdős, Heyde. We apply our results to the Gauss map and obtain new precise asymptotics in the theorem of Lévy on the regular continued fraction expansion of irrational numbers in (0, 1).
Cortical network and connectivity underlying hedonic olfactory perception
Authors: Callara Alejandro Luis , Greco Alberto , Frasnelli Johannes , Rho Gianluca , Vanello Nicola , Scilingo Enzo Pasquale
Published: September 2021

Objective.The emotional response to olfactory stimuli implies the activation of a complex cascade of events triggered by structures lying in the limbic system. However, little is known about how this activation is projected up to cerebral cortex and how different cortical areas dynamically interact each other.Approach.In this study, we acquired EEG from human participants performing a passive odor-perception task with odorants conveying positive, neutral and negative valence. A novel methodological pipeline integrating global field power (GFP), independent component analysis (ICA), dipole source localization was applied to estimate effective connectivity in the challenging scenario of single-trial low-synchronized stimulation.Main results.We identified the brain network and the neural paths, elicited at different frequency bands, i.e.θ(4−7Hz),α(8−12Hz)andβ(13−30Hz), involved in odor valence processing. This brain network includes the orbitofrontal cortex (OFC), the cingulate gyrus (CgG), the superior temporal gyrus (STG), the posterior cingulate cortex/precuneus (PCC/PCu) and the parahippocampal gyrus (PHG). It was analyzed using a time-varying multivariate autoregressive model to resolve time-frequency causal interactions. Specifically, the OFC acts as the main node for odor perception and evaluation of pleasant and unpleasant stimuli, whereas no specific path was observed for a neutral stimulus.Significance.The results introduce new evidences on the role of the OFC during hedonic perception and underpin its specificity during the odor valence assessment. Our findings suggest that, after the odor onset different, bidirectional interactions occur between the OFC and other brain regions associated with emotion recognition/categorization and memory according to the stimulus valence. This outcome unveils how the hedonic olfactory network dynamically changes based on odor valence.
Nano-Schiff base Ligand:Synthesis, Characterization, DFT, and Antibacterial Evaluation of Some Complexes Derived From 4-(-4-methoxybenzylidene)amino) -Antipyrinyl with Glycine amino acid ligand
Authors: Al wagaa Fatima Ali. , Ahmed Sahbaa Ali.
Published: September 2021

Synthesized from a new Neutral tridentate N2O Schiff base 4-(4- methoxybenzylidene)amino)-1,5-dimethyl-2-phenyl-1,2-dihydro-3H-pyrazol-3-one with amino acid ligand.forms stable complexes with transition metal ions such as Co (II), Ni (II), Cu (II), and Cd (II). The complexes were characterized on the basis of their Elemental analysis, molar conductivity, magnetic susceptibility data, IR, 1H-NMR, UV-Vis, XRD, Thermal Analysis (T.G, DTA, DSC), SEM, and Calculation Theoretical studies(DFT). Were used to characterize the complexes. The ligand acts as a tridentate chelating agent, According to physicochemical and spectral results, the ligand acts as a tridentate chelating agent. IR, UV-Vis., and magnetic susceptibility measurements all refer to an octahedral geometry. The general composition of all complexes [M(L)2] is (M=Co(II), Ni(II),Cu(II) and Cd(II), L=(K4-AMetB-Gly) The studies have led to the conclusion that, The coordination sites were established to be oxygen of the carboxyl COO- and two atoms nitrogen of the azomethine (CH=N) group based on the studies. The complexes non-electrolytic nature is verified by the lower conductivity data. The antibacterial activity of the ligand and its complexes was tested against Staphylococcus aureus, Escherichia coli, Klebsiella, and Psedomonas aeruginosa, it was found that these compounds show different activity of inhibition on the growth of the bacteria.
Development of atenolol-tin complexes as PVC photostabilizers for outdoor applications
Authors: Jawad Ali H. , Ahmed Dina S. , Ahmed Azal U. , Salam Baneen , Abdallh Mustafa , Bufaroosha Muna , Hamed Seenar Saad , Yousif Emad
Published: September 2021

New tin complexes were made from the reaction of various tin reagents with atenolol. These complexes were mixed with PVC to produce the stabilized polymeric films. The stability of the films was evaluated using UV/Vis absorption spectroscopy and field emission scanning electron microscopy. The rate of photodecomposition constant have been calculated for PVC films as a method for evaluating the efficiency of atenolol-tin complexes 1–4 that used as a photostabilizers after 300 hour of irradiation. The results have showed that the additives had reduced the rate of photodecomposition constant of PVC films significantly with comparison to PVC (blank). The rate constant of photodecomposition (kd) value for PVC films was higher than that after addition of atenolol tin complexes as photostabilizers.
Preparation and characterization azo dyes derived from 4- hydroxycoumarin and studying their analytical Applications
Authors: Al-Muhsin Alaa A , Fahad T A , Ali A A
Published: September 2021

The preparation 0f azo dyes is the subject of this research. 4-hydroxycoumarin with each ofo-amino benzoic acid (3-[o-Amino benzoic acidazo]-4-hydroxycoumarin]) (B1) and with Sulfa guanidine (3-[Sulfa guanidine azo]-4-hydroxycoumarin) (B2) were syntheses. Azo compounds were characterized by I.R, CHN,1H-NMR Elctronic and Mass spectroscopy. At various pH levels, the electronic spectra of these azo dyes were investigated in terms of acid-base properties, which includes the determination of protonation and ionization constants as well as the establishment of isobestic points. On the electronic spectra, the solvent effect was also investigated at various polarities.