bluuebunny/crossref_metadata_2025 huggingface dataset:
The flow and forming mechanism in the bypass hybrid variable polarity plasma arc additive manufacturing
Authors: Jiang Fan , Li Cheng , Zhang Guokai , Xu Bin , Cheng Wei , Ma Xinqiang , Chen Shujun
Published: July 2023

The bypass hybrid variable polarity plasma arc (VPPA) has the specific ability that could control the current through the wire and base metal independently. It offers a unique advantage for additive manufacturing for adjusting the heat input of wire and base metal freely. The deposition process of molten metal and the forming mechanism of the deposition layer are significantly different with the traditional wire and arc additive manufacturing (WAAM). Therefore, this paper investigates the effects of main current and bypass current on the morphology characteristics of the deposition layer, explores the surface and internal material flow of the molten metal, and constructs a multi-layer morphological model of the deposition layer under this process. The deposition process was observed by a high-speed camera, and the molten metal flow was tracked by slag and copper. It is found that the bypass hybrid VPPA can adjust the morphology of the deposition layer by changing the combination of the main and bypass current. The plasma arc establishes the deposition channel of the molten metal, and the surface flow in the deposition channel tends to stagnate further away from the arc and the mass transfer is in the form of internal filling. The depositing metal is not affected by the hybrid arc in solidification, and the surface tension plays a dominant role in forming. The flow pattern leads to an arch shape cross section of the deposition layer. The work lays a foundation for finely controlling and predicting the morphology of the deposition layer in WAAM.
An artificial dead-layer to protect the ferroelectric thin films from electron injection
Authors: Chen Xiaoyang , Zhang Jie , Huang Binbin , Liu Yun , Yu Ping
Published: July 2023

For ferroelectric (FE) thin films, working in the harsh environment of a high electric field (E) or high temperature (T) remains a great challenge. As a post-treatment approach, dead-layer engineering exhibits a certain generality and could improve the dielectric strength (Eb) via depositing a specially designed artificial “dead-layer” on most of the as-prepared FE thin films. However, physical essence of the artificial dead-layer needs further analysis. Great challenges are the abundant and complicated conduction mechanisms in the FE-based thin films and the lack of adequate research on modulating these conduction mechanisms by this artificial dead-layer. As a vital part of the conduction mechanisms, electron injection can be easily triggered under E and thermal excitation that almost appeared in all FE-based thin films. Here, the ultrathin artificial dead-layer of Ca0.2Zr0.8O1.8 (CSZ) was used to restrain multiple electron injection in low-Eb LaNiO3/Ba0.58Sr0.42TiO3 (LNO/BST) FE thin films, including thermal emission and tunneling effect, under a high E and T, even under an opposite E. It was found that the suppressing effect on the multiple electron-injection mechanisms via the artificial dead-layer mainly comes from its wall-like energy-barrier structure, which is composed of two opposite and high interface energy barriers (BST/CSZ: 2.95 eV, CSZ/Au: 3.92 eV) and a wide depletion layer. The generality of protecting the ferroelectric thin films from electron injection via the artificial dead-layer was discussed.
Low-power and high PPF feature synaptic transistors with 3D interface based on SnO2 nanofibers for neuromorphic application
Authors: Wen Shengkai , Li Jun , Wang Zexin , Zhang Zhenzhao , Zhang Jianhua
Published: July 2023

Featuring excellent computational rates and highly parallel computing, human brain-based neuromorphic devices have attracted the attention of more and more researchers. There have been numerous reports investigating the use of transistors to simulate synaptic functions; however, the majority of the dielectric and channel layers in these devices are layer-stacked structures, which are not conducive to the modulation of the active layers. Moreover, optimizing the paired pulse facilitation index is a critical factor in enhancing the short-term memory of synaptic devices and constructing high-precision synaptic systems, but it has received inadequate attention. In this study, we present a low-cost electrolyte-gated synaptic transistor with three-dimensional (3D) interfacial contacts, in which the channel layer is SnO2 nanofibers, and the 3D interface reduces the power consumption to 9.6 fJ. This study has simulated some important synaptic behaviors; importantly, the PPF value is as high as 223%, which is related to the slow kinetics of sodium ions. In addition, the Ebbinghaus forgetting curve and its application to image memory are also simulated. These findings provide valuable insight for the future development of complex neuromorphic systems.
Phonon-induced magnetization dynamics in Co-doped iron garnets
Authors: Frej A. , Davies C. S. , Kirilyuk A. , Stupakiewicz A.
Published: July 2023

The developing field of strain-induced magnetization dynamics offers a promising path toward efficiently controlling spins and phase transitions. Understanding the underlying mechanisms is crucial in finding the optimal parameters supporting the phononic switching of magnetization. Here, we present an experimental and numerical study of time-resolved magnetization dynamics driven by the resonant excitation of an optical phonon mode in iron garnets. Upon pumping the latter with an infrared pulse obtained from a free-electron laser, we observe spatially varying magnetization precession, with its phase depending on the direction of an external magnetic field. Our micromagnetic simulations effectively describe the magnetization precession and switching in terms of laser-induced changes in the crystal's magneto-elastic energy.
Rational design of quantum spin Hall phase in type-III van der Waals heterostructures
Authors: Xiao Xiaoliang , Xie Zijuan , Kong Weixiang , Fan Jing , Chen Zhongjia , Wang Rui , Wu Xiaozhi
Published: July 2023

Van der Waals heterostructures (vdWHs) are effective platforms for exploring various attractive topological phases. Here, based on the low-energy effective k·p model, we propose that the type-III vdWHs, which were previously considered as only belonging to trivial metallic phases, can realize the nontrivial quantum spin Hall (QSH) effect. We reveal that the band inversion of such a QSH phase is attributed to the band alignment of momentum space matching, i.e., the conduction band minimum and valence band maximum located at the same point in momentum space near the Fermi level. Moreover, using first-principles calculations, we show that the Mg(OH)2/Ga2O2 heterobilayer, a typical type-III vdWH with high thermodynamic stability, is an ideal candidate for achieving our strategy. We further calculate the helical gapless edge states and quantized spin Hall conductance, which are visible inside the global bandgap, thus facilitating the experimental observation. Our work offers a promising pathway for realizing the QSH phase in natural materials.
Robust superconductivity and huge enhancement of upper critical field in Nb2CS2 MXene under high pressure
Authors: Li Chenyi , Dong Qing , Xing Shengyang , Yue Lei , Liu Ran , Liu Bo , Li Quanjun , Fang Yuqiang , Huang Fuqiang , Liu Bingbing
Published: July 2023

As a member of the emerging MXenes family, Nb2CS2 offers distinctive superconductivity, excellent electrical properties, and outstanding chemical stability, making it potentially useful for energy storage, medical imaging, and quantum computing. Herein, we systematically investigate how ultrahigh pressure affects the electrical properties of Nb2CS2. The results indicate that Nb2CS2 retains robust superconductivity with Tc>8 K up to the maximum applied pressure of 146.8 GPa. Moreover, the upper critical magnetic field Hc2(0) of Nb2CS2 increases with pressure, and the Pauli limit is violated at pressures greater than 120 GPa. Meanwhile, Hc2(0) increases to 19.3 T at 146.8 GPa, which is 4.8 times greater than at the initial pressure. Further analysis suggests that the significant enhancement of Hc2(0) below 30 GPa comes from the sharp pressure-induced rise of carrier concentration as the interlayer distance decreases, and the significant increase in Hc2(0) above 86 GPa may come from enhanced spin–orbit coupling or the possible unconventional superconducting pairing mechanisms. These results provide insights into the superconducting properties of MXene materials and offer guidelines for further research on electronic transport in Mxenes under ultrahigh pressure.
Coexistence of infrared plasmon and thermoelectricity in rare-earth semiconducting ytterbium nitride
Authors: Loyal Mehak , Biswas Bidesh , Das Prasanna , Saha Bivas
Published: July 2023

Rare-earth nitride (REN) pnictides are exciting materials due to their localized and strongly correlated 4f-electrons that lead to interesting magnetic properties useful for spintronic devices. Ytterbium nitride (YbN) is a unique rare-earth pnictide as it exhibits antiferromagnetic ground states, unlike most ferromagnetic RENs. Though the magnetic properties of YbN thin films have been studied before, the electronic, thermoelectric, and plasmonic properties of YbN are yet to be investigated. Here, we show coexisting high thermoelectric power factor and short-wavelength infrared plasmon polaritons in epitaxial YbN thin films deposited with the ultrahigh vacuum growth method. YbN thin films deposited on (001) MgO substrates exhibit epitaxial and good quality crystalline growth and exhibit a high thermoelectric power factor of ∼ 1.9 mW/mK2 at 750 K due to high electrical conductivity and a moderately high Seebeck coefficient. High carrier concentration also leads to a positive-to-negative dielectric permittivity transition in YbN at ∼1900–1950 nm, corresponding to the epsilon-near-zero plasmonic resonance. Low-temperature transport measurements revealed that dislocation and acoustic phonon scattering dominate electronic transport. Demonstration of coexisting high thermoelectric power factor and infrared plasmon polaritons marks important progress in designing YbN-based thermoelectric and plasmonic devices for future applications.
Pangenome analyses reveal impact of transposable elements and ploidy on the evolution of potato species
Authors: Bozan Ilayda , Achakkagari Sai Reddy , Anglin Noelle L. , Ellis David , Tai Helen H. , Strömvik Martina V.
Published: July 2023

Potato (
Solanum sp
., family Solanaceae) is the most important noncereal food crop globally. It has over 100 wild relatives in the
Solanum
section
Petota
, which features species with both sexual and asexual reproduction and varying ploidy levels. A pangenome of
Solanum
section
Petota
composed of 296 accessions was constructed including diploids and polyploids compared via presence/absence variation (PAV). The
Petota
core (genes shared by at least 97% of the accessions) and shell genomes (shared by 3 to 97%) are enriched in basic molecular and cellular functions, while the cloud genome (genes present in less than 3% of the member accessions) showed enrichment in transposable elements (TEs). Comparison of PAV in domesticated vs. wild accessions was made, and a phylogenetic tree was constructed based on PAVs, grouping accessions into different clades, similar to previous phylogenies produced using DNA markers. A cladewise pangenome approach identified abiotic stress response among the core genes in clade 1+2 and clade 3, and flowering/tuberization among the core genes in clade 4. The TE content differed between the clades, with clade 1+2, which is composed of species from North and Central America with reproductive isolation from species in other clades, having much lower TE content compared to other clades. In contrast, accessions with in vitro propagation history were identified and found to have high levels of TEs. Results indicate a role for TEs in adaptation to new environments, both natural and artificial, for
Solanum
section
Petota
.
Pinoresinol rescues developmental phenotypes of Arabidopsis phenylpropanoid mutants overexpressing
FERULATE 5-HYDROXYLASE
Authors: Muro-Villanueva Fabiola , Pysh Leonard D. , Kim Hoon , Bouse Tyler , Ralph John , Luo Zhiwei , Cooper Bruce R. , Jannasch Amber S. , Zhang Zeyu , Gu Chong , Chapple Clint
Published: July 2023

Most phenylpropanoid pathway flux is directed toward the production of monolignols, but this pathway also generates multiple bioactive metabolites. The monolignols coniferyl and sinapyl alcohol polymerize to form guaiacyl (G) and syringyl (S) units in lignin, components that are characteristic of plant secondary cell walls. Lignin negatively impacts the saccharification potential of lignocellulosic biomass. Although manipulation of its content and composition through genetic engineering has reduced biomass recalcitrance, in some cases, these genetic manipulations lead to impaired growth. The reduced-growth phenotype is often attributed to poor water transport due to xylem collapse in low-lignin mutants, but alternative models suggest that it could be caused by the hyper- or hypoaccumulation of phenylpropanoid intermediates. In
Arabidopsis thaliana
, overexpression of
FERULATE 5-HYDROXYLASE
(
F5H
) shifts the normal G/S lignin ratio to nearly pure S lignin and does not result in substantial changes to plant growth. In contrast, when we overexpressed
F5H
in the low-lignin mutants
cinnamyl dehydrogenase c
and
d
(
cadc cadd
),
cinnamoyl-CoA reductase 1
, and
reduced epidermal fluorescence 3
, plant growth was severely compromised. In addition,
cadc cadd
plants overexpressing
F5H
exhibited defects in lateral root development. Exogenous coniferyl alcohol (CA) and its dimeric coupling product, pinoresinol, rescue these phenotypes. These data suggest that mutations in the phenylpropanoid pathway limit the biosynthesis of pinoresinol, and this effect is exacerbated by overexpression of
F5H
, which further draws down cellular pools of its precursor, CA. Overall, these genetic manipulations appear to restrict the synthesis of pinoresinol or a downstream metabolite that is necessary for plant growth.
Redefining the human corneal immune compartment using dynamic intravital imaging
Authors: Downie Laura E. , Zhang Xinyuan , Wu Mengliang , Karunaratne Senuri , Loi Joon Keit , Senthil Kirthana , Arshad Sana , Bertram Kirstie , Cunningham Anthony L. , Carnt Nicole , Mueller Scott N. , Chinnery Holly R.
Published: July 2023

The healthy human cornea is a uniquely transparent sensory tissue where immune responses are tightly controlled to preserve vision. The cornea contains immune cells that are widely presumed to be intraepithelial dendritic cells (DCs). Corneal immune cells have diverse cellular morphologies and morphological alterations are used as a marker of inflammation and injury. Based on our imaging of corneal T cells in mice, we hypothesized that many human corneal immune cells commonly defined as DCs are intraepithelial lymphocytes (IELs). To investigate this, we developed functional in vivo confocal microscopy (Fun-IVCM) to investigate cell dynamics in the human corneal epithelium and stroma. We show that many immune cells resident in the healthy human cornea are T cells. These corneal IELs are characterized by rapid, persistent motility and interact with corneal DCs and sensory nerves. Imaging deeper into the corneal stroma, we show that crawling macrophages and rare motile T cells patrol the tissue. Furthermore, we identify altered immune cell behaviors in response to short-term contact lens wear (acute inflammatory stimulus), as well as in individuals with allergy (chronic inflammatory stimulus) that was modulated by therapeutic intervention. These findings redefine current understanding of immune cell subsets in the human cornea and reveal how resident corneal immune cells respond and adapt to chronic and acute stimuli.
Both intratumoral regulatory T cell depletion and CTLA-4 antagonism are required for maximum efficacy of anti-CTLA-4 antibodies
Authors: Lax Brianna M. , Palmeri Joseph R. , Lutz Emi A. , Sheen Allison , Stinson Jordan A. , Duhamel Lauren , Santollani Luciano , Kennedy Alan , Rothschilds Adrienne M. , Spranger Stefani , Sansom David M. , Wittrup K. Dane
Published: July 2023

Anti-CTLA-4 antibodies have successfully elicited durable tumor regression in the clinic; however, long-term benefit is limited to a subset of patients for select cancer indications. The incomplete understanding of their mechanism of action has hindered efforts at improvement, with conflicting hypotheses proposing either antagonism of the CTLA-4:B7 axis or Fc effector-mediated regulatory T cell (Treg) depletion governing efficacy. Here, we report the engineering of a nonantagonistic CTLA-4 binding domain (b1s1e2) that depletes intratumoral Tregs as an Fc fusion. Comparison of b1s1e2-Fc to 9d9, an antagonistic anti-CTLA-4 antibody, allowed for interrogation of the separate contributions of CTLA-4 antagonism and Treg depletion to efficacy. Despite equivalent levels of intratumoral Treg depletion, 9d9 achieved more long-term cures than b1s1e2-Fc in MC38 tumors, demonstrating that CTLA-4 antagonism provided additional survival benefit. Consistent with prior reports that CTLA-4 antagonism enhances priming, treatment with 9d9, but not b1s1e2-Fc, increased the percentage of activated T cells in the tumor-draining lymph node (tdLN). Treg depletion with either construct was restricted to the tumor due to insufficient surface CTLA-4 expression on Tregs in other compartments. Through intratumoral administration of diphtheria toxin in Foxp3-DTR mice, we show that depletion of both intratumoral and nodal Tregs provided even greater survival benefit than 9d9, consistent with Treg-driven restraint of priming in the tdLN. Our data demonstrate that anti-CTLA-4 therapies require both CTLA-4 antagonism and intratumoral Treg depletion for maximum efficacy—but that potential future therapies also capable of depleting nodal Tregs could show efficacy in the absence of CTLA-4 antagonism.
Water-assisted strong underwater adhesion via interfacial water removal and self-adaptive gelation
Authors: Qin Chenxi , Ma Yanfei , Zhang Zhizhi , Du Yingjie , Duan Sidi , Ma Shuanhong , Pei Xiaowei , Yu Bo , Cai Meirong , He Ximin , Zhou Feng
Published: July 2023

In nearly all cases of underwater adhesion, water molecules typically act as a destroyer. Thus, removing interfacial water from the substrate surfaces is essential for forming super-strong underwater adhesion. However, current methods mainly rely on physical means to dislodge interfacial water, such as absorption, hydrophobic repulsion, or extrusion, which are inefficient in removing obstinate hydrated water at contact interface, resulting in poor adhesion. Herein, we present a unique means of reversing the role of water to assist in realizing a self-strengthening liquid underwater adhesive (SLU-adhesive) that can effectively remove water at contact interface. This is achieved through multiscale physical–chemical coupling methods across millimeter to molecular levels and self-adaptive strengthening of the cohesion during underwater operations. As a result, strong adhesion over 1,600 kPa (compared to ~100 to 1,000 kPa in current state of the art) can be achieved on various materials, including inorganic metal and organic plastic materials, without preloading in different environments such as pure water, a wide range of pH solutions (pH = 3 to 11), and seawater. Intriguingly, SLU-adhesive/photothermal nanoparticles (carbon nanotubes) hybrid materials can significantly reduce the time required for complete curing from 24 h to 40 min using near-infrared laser radiation due to unique thermal-response of the chemical reaction rate. The excellent adhesion property and self-adaptive adhesion procedure allow SLU-adhesive materials to demonstrate great potential for broad applications in underwater sand stabilization, underwater repair, and even adhesion failure detection as a self-reporting adhesive. This concept of “water helper” has potential to advance underwater adhesion and manufacturing strategies.
Inactive PARP1 causes embryonic lethality and genome instability in a dominant-negative manner
Authors: Shao Zhengping , Lee Brian J. , Zhang Hanwen , Lin Xiaohui , Li Chen , Jiang Wenxia , Chirathivat Napon , Gershik Steven , Shen Michael M. , Baer Richard , Zha Shan
Published: July 2023

PARP1 (poly-ADP ribose polymerase 1) is recruited and activated by DNA strand breaks, catalyzing the generation of poly-ADP-ribose (PAR) chains from NAD+. PAR relaxes chromatin and recruits other DNA repair factors, including XRCC1 and DNA Ligase 3, to maintain genomic stability. Here we show that, in contrast to the normal development of Parp1-null mice, heterozygous expression of catalytically inactive Parp1 (E988A,

Parp1
+/A

) acts in a dominant-negative manner to disrupt murine embryogenesis. As such, all the surviving F1

Parp1
+/A

mice are chimeras with mixed

Parp1
+/AN

(neoR retention) cells that act similarly to

Parp1
+/−

. Pure F2

Parp1
+/A

embryos were found at Mendelian ratios at the E3.5 blastocyst stage but died before E9.5. Compared to

Parp1
−/−

cells, genotype and expression-validated pure

Parp1
+/A

cells retain significant ADP-ribosylation and PARylation activities but accumulate markedly higher levels of sister chromatid exchange and mitotic bridges. Despite proficiency for homologous recombination and nonhomologous end-joining measured by reporter assays and supported by normal lymphocyte and germ cell development,

Parp1
+/A

cells are hypersensitive to base damages, radiation, and Topoisomerase I and II inhibition. The sensitivity of

Parp1
+/A

cells to base damages and Topo inhibitors exceed

Parp1
−/−

controls. The findings show that the enzymatically inactive PARP1 dominant negatively blocks DNA repair in selective pathways beyond wild-type PARP1 and establishes a crucial physiological difference between PARP1 inactivation vs. deletion. As a result, the expression of enzymatically inactive PARP1 from one allele is sufficient to abrogate murine embryonic development, providing a mechanism for the on-target side effect of PARP inhibitors used for cancer therapy.
Resolvin D1 prevents injurious neutrophil swarming in transplanted lungs
Authors: Li Wenjun , Shepherd Hailey M. , Terada Yuriko , Shay Ashley E. , Bery Amit I. , Gelman Andrew E. , Lavine Kory J. , Serhan Charles N. , Kreisel Daniel
Published: July 2023

Neutrophils are the primary cell type involved in lung ischemia-reperfusion injury (IRI), which remains a frequent and morbid complication after organ transplantation. Endogenous lipid mediators that become activated during acute inflammation-resolution have gained increasing recognition for their protective role(s) in promoting the restoration of homeostasis, but their influence on early immune responses following transplantation remains to be uncovered. Resolvin D1, 7
S
,8
R
,17
S
-trihydroxy-4
Z
,9
E
,11
E
,13
Z
,15
E
,19
Z
-docosahexaenoic acid (RvD1), is a potent stereoselective mediator that exhibits proresolving and anti-inflammatory actions in the setting of tissue injury. Here, using metabololipidomics, we demonstrate that endogenous proresolving mediators including RvD1 are increased in human and murine lung grafts immediately following transplantation. In mouse grafts, we observe lipid mediator class switching early after reperfusion. We use intravital two-photon microscopy to reveal that RvD1 treatment significantly limits early neutrophil infiltration and swarming, thereby ameliorating early graft dysfunction in transplanted syngeneic lungs subjected to severe IRI. Through integrated analysis of single-cell RNA sequencing data of donor and recipient immune cells from lung grafts, we identify transcriptomic changes induced by RvD1. These results support a role for RvD1 as a potent modality for preventing early neutrophil-mediated tissue damage after lung IRI that may be therapeutic in the clinics.
Photocatalytic chlorine atom production on mineral dust–sea spray aerosols over the North Atlantic
Authors: van Herpen Maarten M. J. W. , Li Qinyi , Saiz-Lopez Alfonso , Liisberg Jesper B. , Röckmann Thomas , Cuevas Carlos A. , Fernandez Rafael P. , Mak John E. , Mahowald Natalie M. , Hess Peter , Meidan Daphne , Stuut Jan-Berend W. , Johnson Matthew S.
Published: July 2023

Active chlorine in the atmosphere is poorly constrained and so is its role in the oxidation of the potent greenhouse gas methane, causing uncertainty in global methane budgets. We propose a photocatalytic mechanism for chlorine atom production that occurs when Sahara dust mixes with sea spray aerosol. The mechanism is validated by implementation in a global atmospheric model and thereby explaining the episodic, seasonal, and location-dependent13C depletion in CO in air samples from Barbados [J.E. Mak, G. Kra, T. Sandomenico, P. Bergamaschi,J. Geophys. Res. Atmos.108(2003)], which remained unexplained for decades. The production of Cl can also explain the anomaly in the CO:ethane ratio found at Cape Verde [K. A. Read et al.,J. Geophys. Res. Atmos.114(2009)], in addition to explaining the observation of elevated HOCl [M. J. Lawler et al.,Atmos. Chem. Phys.11, 7617–7628 (2011)]. Our model finds that 3.8 Tg(Cl) y−1is produced over the North Atlantic, making it the dominant source of chlorine in the region; globally, chlorine production increases by 41%. The shift in the methane sink budget due to the increased role of Cl means that isotope-constrained top–down models fail to allocate 12 Tg y−1(2% of total methane emissions) to13C-depleted biological sources such as agriculture and wetlands. Since 2014, an increase in North African dust emissions has increased the13C isotope of atmospheric CH4, thereby partially masking a much greater decline in this isotope, which has implications for the interpretation of the drivers behind the recent increase of methane in the atmosphere.
Origin of the OAS–RNase L innate immune pathway before the rise of jawed vertebrates via molecular tinkering
Authors: Chu Lingyu , Gong Zhen , Wang Wenqiang , Han Guan-Zhu
Published: July 2023

Discriminating self from nonself is fundamental to immunity. Yet, it remains largely elusive how the mechanisms of self and nonself discrimination originated. Sensing double-stranded RNA as nonself, the 2′,5′-oligoadenylate synthetase (OAS)–ribonuclease L (RNase L) pathway represents a crucial component of innate immunity. Here, we combine phylogenomic and functional analyses to show that the functional OAS–RNase L pathway likely originated through tinkering with preexisting proteins before the rise of jawed vertebrates during or before the Silurian period (444 to 419 Mya). Multiple concerted losses of OAS and RNase L occurred during the evolution of jawed vertebrates, further supporting the ancient coupling between OAS and RNase L. Moreover, both
OAS
and
RNase L
genes evolved under episodic positive selection across jawed vertebrates, suggesting a long-running evolutionary arms race between the OAS–RNase L pathway and microbes. Our findings illuminate how an innate immune pathway originated via molecular tinkering.
Theoretical isotherm equation for adsorption-induced structural transition on flexible metal–organic frameworks
Authors: Hiraide Shotaro , Sakanaka Yuta , Iida Yuya , Arima Homare , Miyahara Minoru T. , Watanabe Satoshi
Published: July 2023

Flexible metal–organic frameworks (MOFs) exhibit an adsorption-induced structural transition known as “gate opening” or “breathing,” resulting in an S-shaped adsorption isotherm. This unique feature of flexible MOFs offers significant advantages, such as a large working capacity, high selectivity, and intrinsic thermal management capability, positioning them as crucial candidates for revolutionizing adsorption separation processes. Therefore, the interest in the industrial applications of flexible MOFs is increasing, and the adsorption engineering for flexible MOFs is becoming important. However, despite the establishment of the theoretical background for adsorption-induced structural transitions, no theoretical equation is available to describe S-shaped adsorption isotherms of flexible MOFs. Researchers rely on various empirical equations for process simulations that can lead to unreliable outcomes or may overlook insights into improving material performance owing to parameters without physical meaning. In this study, we derive a theoretical equation based on statistical mechanics that could be a standard for the structural transition type adsorption isotherms, as the Langmuir equation represents type I isotherms. The versatility of the derived equation is shown through four examples of flexible MOFs that exhibit gate opening and breathing. The consistency of the formula with existing theories, including the osmotic free energy analysis and intrinsic thermal management capabilities, is also discussed. The developed theoretical equation may lead to more reliable and insightful outcomes in adsorption separation processes, further advancing the direction of industrial applications of flexible MOFs.
An expandable, modular de novo protein platform for precision redox engineering
Authors: Hutchins George H. , Noble Claire E. M. , Bunzel H. Adrian , Williams Christopher , Dubiel Paulina , Yadav Sathish K. N. , Molinaro Paul M. , Barringer Rob , Blackburn Hector , Hardy Benjamin J. , Parnell Alice E. , Landau Charles , Race Paul R. , Oliver Thomas A. A. , Koder Ronald L. , Crump Matthew P. , Schaffitzel Christiane , Oliveira A. Sofia F. , Mulholland Adrian J. , Anderson J. L. Ross
Published: July 2023

The electron-conducting circuitry of life represents an as-yet untapped resource of exquisite, nanoscale biomolecular engineering. Here, we report the characterization and structure of a de novo diheme “maquette” protein, 4D2, which we subsequently use to create an expanded, modular platform for heme protein design. A well-folded monoheme variant was created by computational redesign, which was then utilized for the experimental validation of continuum electrostatic redox potential calculations. This demonstrates how fundamental biophysical properties can be predicted and fine-tuned. 4D2 was then extended into a tetraheme helical bundle, representing a 7 nm molecular wire. Despite a molecular weight of only 24 kDa, electron cryomicroscopy illustrated a remarkable level of detail, indicating the positioning of the secondary structure and the heme cofactors. This robust, expressible, highly thermostable and readily designable modular platform presents a valuable resource for redox protein design and the future construction of artificial electron-conducting circuitry.
Unnexin is a protein subunit of a large-pore channel expressed by unicellular organisms
Authors: Güiza Juan , Solís Francisco , Valenzuela Bernardita , Arancibia Duxan , Zamorano Pedro , González Jorge , Saavedra Jonathan , Neely Alan , Salgado Magdiel , Martínez Agustín D. , Sáez Juan C. , Vega José L.
Published: July 2023

Cells of vertebrate and invertebrate organisms express proteins specialized in membrane channel–based cell–cell communication that are absent in unicellular organisms. We recently described the prediction of some members of the large-pore channel family in kinetoplastids, consisting of proteins called unnexins, which share several structural features with innexin and pannexin proteins. Here, we demonstrated that the unnexin1 protein (Unx1) is delivered to the cell membrane, displaying a topology consisting of four transmembrane domains with C and N termini on the cytoplasmic side and form large-pore channels that are permeable to small molecules. Low extracellular Ca
2+
/Mg
2+
levels or extracellular alkalinization, but not mechanical stretching, increases channel activity. The Unx1 channel mediates the influx of Ca
2+
and does not form intercellular dye coupling between HeLa Unx1 transfected cells. Unx1 channel function was further evidenced by its ability to mediate ionic currents when expressed in
Xenopus
oocytes. Downregulation of Unx1 mRNA with morpholine contains
Trypanosoma cruzi
invasion. Phylogenetic analysis revealed the presence of Unx1 homologs in other protozoan parasites, suggesting a conserved function for these channel parasites in other protists. Our data demonstrate that Unx1 forms large-pore membrane channels, which may serve as a diffusional pathway for ions and small molecules that are likely to be metabolic substrates or waste products, and signaling autocrine and paracrine molecules that could be involved in cell invasion. As morpholinos-induced downregulation of Unx1 reduces the infectivity of trypomastigotes, the Unx1 channels might be an attractive target for developing trypanocide drugs.
Father’s care uniquely influences male neurodevelopment
Authors: Danoff Joshua S. , Ramos Erin N. , Hinton Taylor D. , Perkeybile Allison M. , Graves Andrew J. , Quinn Graham C. , Lightbody-Cimer Aaron R. , Gordevičius Juozas , Milčiūtė Milda , Brooke Robert T. , Carter C. Sue , Bales Karen L. , Erisir Alev , Connelly Jessica J.
Published: July 2023

Mammalian infants depend on parental care for survival, with numerous consequences for their behavioral development. We investigated the epigenetic and neurodevelopmental mechanisms mediating the impact of early biparental care on development of alloparenting behavior, or caring for offspring that are not one’s own. We find that receiving high parental care early in life leads to slower epigenetic aging of both sexes and widespread male-specific differential expression of genes related to synaptic transmission and autism in the nucleus accumbens. Examination of parental care composition indicates that high-care fathers promote a male-specific increase in excitatory synapses and increases in pup retrieval behavior as juveniles. Interestingly, females raised by high-care fathers have the opposite behavioral response and display fewer pup retrievals. These results support the concept that neurodevelopmental trajectories are programmed by different features of early-life parental care and reveal that male neurodevelopmental processes are uniquely sensitive to care by fathers.
Teaching during COVID-19
Authors: Burgo Clara
Published: July 2023

Latinx who do not feel confident speaking Spanish are usually questioned. To fight these ideologies, Pascual and Cabo and Prada (2018) suggest new pedagogical approaches to incorporate in the curriculum the experiences of the heritage language learner (HLL). Latinx in higher education expect a culturally relevant curriculum to critically listen and speak to challenge the hierarchies that marginalize them. Why is social justice education key? To meet the needs of our minority students and to fight social inequities that affect their lives (Freire, 2021). This article offers a proposal to teach social justice in the HLL classroom through classroom strategies such as digital stories, autoethnographies, creative writing, or oral history to provide these students with the tools they need to give voice to their communities and incorporate them in the curriculum of an inclusive Spanish classroom whose backbone is US Spanish to fight raciolinguistic ideologies that marginalize them.
The localization of food- and drink-related items in video games
Authors: Al-Batineh Mohammed
Published: July 2023

This study examines the localization of food- and drink-related items in The Witcher 3 (2015). It
analyzes the original English and Arabic versions using the corpus approach. A list of food- and drink-related lexemes was
extracted from the English original game and these lexemes were traced to their context in the English and Arabic versions using
the concordance function in Sketch Engine. The concordance analysis focused on the translation strategies adopted to localize
food- and drink-related lexemes into Arabic and on the success of the translation in the socio-cultural and religious contexts of
the target culture. The data reveals that foreign food-related terms are mostly domesticated, whereas drink-related terms are
foreignized. The findings of this study suggest that foreignization strategies can be used for localization purposes to create a
target video game that minimizes the cultural gaps between the source and target cultures and provides a less disruptive gaming
experience.
The Middle English prepositional dative
Authors: Ingham Richard P.
Published: July 2023

The to-PP form of the dative alternation is
argued to have arisen from contact with French rather than being linked to
the loss of the Old English Dative case. It is shown to have been extended
in ME to the experiencer argument of psych verbs, and to the recipient
argument of some verbs of communication, but only to those whose French
counterparts took the à-dative, regardless of OE case
assignment. Where French equivalents of verbs in these classes did not take
an indirect object, the Middle English verb took only a nominal object.
Selectivity in to-PP use in ME, going beyond verbs of
possession transfer yet showing a verb-specific restriction to source item
argument realisation patterns, indicates that French provided a replication
source for the to-PP form of the dative alternation.
Ditransitive constructions in the history of German
Authors: Rauth Philipp
Published: July 2023

In modern Standard German, the base order of direct and indirect
full noun objects in the ‘Mittelfeld’ is considered to be IO>DO.
Deviation from this order is influenced by various linguistic factors such
as prosody, complexity, syntactic structure, animacy, definiteness, and
information structure. Does this also hold for dialectal and historical
varieties of German? In order to answer this question, I present results of
a comprehensive diachronic corpus study (8th–20th century) on the
significance of these factors, which in sum involved about 2,100 instances
of ditransitives. My data shows that, at least since the 11th century,
information structure has been the most important and stable factor for the
inversion of the base order: A given or more salient DO significantly
increases the likelihood for DO>IO. However, IO>DO remains the
predominant order throughout the history of German.
A versatile approach for the immobilization of lead-free Cs3Bi2I9 perovskites for photocatalytic CO2 reduction
Authors: Quintero-Lizárraga Oscar L , Luévano-Hipólito Edith , Torres-Martínez Leticia M
Published: July 2023

This work proposes a novel approach to immobilize the lead-free bismuth halide perovskite Cs3Bi2I9 in mica and cellular porous concrete supports. The perovskites were evaluated as visible-light active photocatalysts in the CO2 reduction to generate HCOOH with high energy conversion efficiencies. The approach ensured the material’s stability exposed to an aqueous medium under visible light irradiation. According to the results, the Cs3Bi2I9 particles exhibited a different morphology depending on the support used; its growth on mica favored the formation of well-defined hexagonal particles. Meanwhile, the porous concrete favored the formation of needle-like particles. Also, the optical characterization indicated that when the Cs3Bi2I9 particles grew as a thin film, their surface energy seemed higher, favoring the formation of layered structures related to the lattice defects. On the other hand, the concrete cellular offers a porous interconnected network, an excellent medium to encapsulate the Cs3Bi2I9 particles. These properties favored the formation of 2,570 µmol of HCOOH in the steady state with an energy conversion efficiency of up to 24.3%, which is higher than the required value to scale up the process. The analysis of the perovskite after the reaction revealed that the sample maintains its properties, and it shows the growth of flake-like particles on top of hexagonal particles, which eventually participate in the photocatalytic reaction. Also, it was demonstrated that the approach implemented here favored high thermal stability of the Cs3Bi2I9 perovskite.
Transport across junctions of altermagnets with normal metals and ferromagnets
Authors: Das Sachchidanand , Suri Dhavala , Soori Abhiram
Published: July 2023

Altermagnet (AM) is a novel time reversal symmetry broken magnetic phase withd-wave order which has been experimentally realized recently. We discuss theoretical models of AM based systems on lattice and in continuum. We show equivalence between the lattice and continuum models by mapping the respective parameters. We study (i) AM-normal metal and (ii) AM-ferromagnet (FM) junctions, with the aim to quantify transport properties such as conductivity and magnetoresistance. We find that a spin current accompanies charge current when a bias is applied. The magnetoresistance of AM-FM junction switches sign when AM is rotated by 90∘—a feature unique to the altermagnetic phase.
Band engineering enhances thermoelectric performance of Ag-doped Sn0.98Se
Authors: Zhu Jianglong , Zhang Fujie , Tan Xiaobo , Li Ruiheng , He Shan , Ang Ran
Published: July 2023

Ag doping can effectively increase the carrier concentration of p-type SnSe polycrystalline, thereby enhancing the thermoelectric (TE) performance. However, the key role of the transport valence band in Ag-doped SnSe remains unclear. Particularly, understanding the influence of evaluating the optimal balance between band convergence and carrier mobility on weighted mobility is a primary consideration in designing high-performance TE materials. Here, we strongly confirm through theoretical and experimental evidence that Ag-doped Sn0.98Se can promote the evolution of valence bands and achieve band convergence and density of states distortion. The significantly increased carrier concentration and effective mass result in a dramatic increase in weighted mobility, which favors the achievement of superior power factors. Furthermore, the Debye model reveals the reasons for the evolution of lattice thermal conductivity. Eventually, a superior average power factor and average zT value are obtained in the Ag-doped samples in both directions over the entire test temperature range. This strategy of improving TE performance through band engineering provides an effective way to advance TEs.
Network dynamics with higher-order interactions: coupled cell hypernetworks for identical cells and synchrony
Authors: Aguiar Manuela , Bick Christian , Dias Ana
Published: July 2023

Network interactions that are nonlinear in the state of more than two nodes—also known as higher-order interactions—can have a profound impact on the collective network dynamics. Here we develop a coupled cell hypernetwork formalism to elucidate the existence and stability of (cluster) synchronization patterns in network dynamical systems with higher-order interactions. More specifically, we define robust synchrony subspace for coupled cell hypernetworks whose coupling structure is determined by an underlying hypergraph and describe those spaces for general such hypernetworks. Since a hypergraph can be equivalently represented as a bipartite graph between its nodes and hyperedges, we relate the synchrony subspaces of a hypernetwork to balanced colourings of the corresponding incidence digraph.
Evaluation of the feasibility of a multisource CBCT for maxillofacial imaging
Authors: Xu Shuang , Li Boyuan , Inscoe Christina R , Bastawros Daniel , Tyndall Donald A , Lee Yueh Z , Lu Jianping , Zhou Otto
Published: July 2023

Objective. The aim of this study was to investigate the feasibility of improving the image quality and accuracy of cone beam computed tomography (CBCT) by replacing the conventional wide cone angle x-ray tube with a distributed x-ray source array positioned in the axial direction. Approach. The multisource CBCT (ms-CBCT) design was experimentally simulated using a benchtop scanner with a carbon nanotube x-ray tube and a flat-panel detector. The source was collimated and translated in the axial direction to simulate a source array with a reduced cone angle for each beam. An adjacent scatter ratio subtraction (ASRS) method was implemented for residual scatter reduction. Several phantoms were imaged using the ms-CBCT and conventional CBCT configurations under otherwise similar conditions. The Requirements of the ms-CBCT design on the x-ray source and detector were evaluated. Main results. Compared to the conventional CBCT, the ms-CBCT design with 8 sources and ASRS significantly improved the image quality and accuracy, including: (1) reducing the cupping artifact from 15% to 3.5%; (2) reducing the spatial nonuniformity of the CT Hounsfield unit values from 38.0 to 9.2; (3) improving the contrast-to-noise ratio of the low contrast objects (acrylic and low density polyethylene inserts) against the water-equivalent background by ∼20% and (4) reducing the root-mean-square error of the HU values by 70%, from 420.1 to 124.4. The imaging dose and scanning time used by the current clinical CBCT for maxillofacial imaging can be achieved by current source and detector technologies. Significance. The ms-CBCT design significantly reduces the scatter and improves the image quality and accuracy compared to the conventional CBCT.
Laser absorption spectroscopy for plasma-assisted thermochemical treatment. Part I.: Applicability of the Beer–Lambert law and interpretation of spectroscopic data
Authors: Pipa A V , Puth A , Böcker J , Jafarpour S M , Dalke A , Biermann H , Röpcke J , van Helden J H
Published: July 2023

The work is devoted to the development of laser absorption spectroscopy (LAS) of plasma-assisted processes for application under industrial conditions. The interpretation of the LAS measurements was revised by taking into consideration the temperature gradient along the absorption path, which is unavoidable in a reactor for thermochemical treatment. The revision is based on the measurement of

H
C
N

,

N

H
3

,

H
2

O

and

C
O

molecular lines in an industrial-scale, active screen plasma nitrocarburizing reactor with a steel active screen. It shows that an effective temperature determined from Doppler broadening could be assigned to each measured spectral line. The effective temperature does not only reflect the temperature gradients along the line-of-sight but also the line strength dependence on temperature for the specific spectroscopic transition. Lower limit estimates of the molecular densities are proposed based on the determined effective temperatures under the assumption of a Boltzmann distribution of the population density over the molecular levels at any local volume of the reactor. For a more accurate interpretation of LAS data of plasma-assisted processes, the spatial distribution of the temperature along line-of-sight has to be known and needs to be taken into account to obtain the molecular densities.
Mapping dynamical systems with distributed time delays to sets of ordinary differential equations
Authors: Henrik Nevermann Daniel , Gros Claudius
Published: July 2023

Real-world dynamical systems with retardation effects are described in general not by a single, precisely defined time delay, but by a range of delay times. An exact mapping onto a set of N + 1 ordinary differential equations exists when the respective delay distribution is given in terms of a gamma distribution with discrete exponents. The number of auxiliary variables one needs to introduce, N, is inversely proportional to the variance of the delay distribution. The case of a single delay is therefore recovered when

N
→
∞

. Using this approach, denoted here the ‘kernel series framework’, we examine systematically how the bifurcation phase diagram of the Mackey–Glass system changes under the influence of distributed delays. We find that local properties, f.i. the locus of a Hopf bifurcation, are robust against the introduction of broadened memory kernels. Period-doubling transitions and the onset of chaos, which involve non-local properties of the flow, are found in contrast to be more sensitive to distributed delays. In general, the observed effects are found to scale as

1

/

N

. Furthermore, we consider time-delayed systems exhibiting chaotic diffusion, which is present in particular for sinusoidal flows. We find that chaotic diffusion is substantially more pronounced for distributed delays. Our results indicate in consequence that modeling approaches of real-world processes should take the effects of distributed delay times into account.