bluuebunny/crossref_metadata_2025 huggingface dataset:
Prediction of anomalous LA-TA splitting in electrides
Authors: Zhang Leilei , Geng Hua Y. , Wu Q.
Published: April 2021

Electrides are an emerging class of materials with excess electrons localized in interstices and acting as anionic interstitial quasi-atoms (ISQs). The spatial ion–electron separation means that electrides can be treated physically as ionic crystals, and this unusual behavior leads to extraordinary physical and chemical phenomena. Here, a completely different effect in electrides is predicted. By recognizing the long-range Coulomb interactions between matrix atoms and ISQs that are unique in electrides, a nonanalytic correction to the forces exerted on the matrix atoms is proposed. This correction gives rise to a longitudinal acoustic-transverse acoustic splitting in the acoustic branch of lattice phonons near the zone center, similar to the well-known longitudinal optical–transverse optical splitting in the phonon spectra of ionic compounds. The factors that govern this splitting are investigated, with isotropic fcc-Li and anisotropic hP4-Na as the typical examples. It is found that not all electrides can induce a detectable splitting, and criteria are given for this type of splitting. The present prediction unveils the rich phenomena in electrides and could lead to unprecedented applications.
Wavepacket propagations for the early time dynamics of proton-coupled electron transfer in the charge-transfer state of NH3Cl complex
Authors: Ariyageadsakul Pinit , Baeck Kyoung Koo
Published: April 2021

A charge-transfer (CT) excited state of NH3Cl, generated by photo-detachment of an electron from the anionic NH3Cl− precursor, can be represented as H2N+–H–Cl− and proceeds to two chemical reactions: one reaction generating NH2 and HCl resulting from a proton transfer (PT) and the other reaction producing NH3 and a Cl atom resulting from an electron transfer (ET); both are coupled to form a typical proton-coupled electron transfer (PCET) process. The early time dynamics of this CT were studied using time-dependent wavepacket propagation on three nonadiabatically coupled electronic states in a reduced three-dimensional space. The electronic states were treated using the XMS-CASPT2/aug-cc-pVTZ ab initio methodology. The population dynamics of the three coupled electronic states were analyzed in detail to reveal the initial stage of the PCET process up to ∼100 fs, while the branching ratio, χ = PT/(ET+PT), was determined after wavepacket propagations of up to 2000 fs. Another main result is the dependence of χ on the vibration levels of the initial precursor anion and the isotope substitution of the connecting H atom with deuterium and tritium. Our study reveals the detailed microscopic features of the PCET process embedded in the CT state of the NH3Cl complex and certain systematic dependences of the branching ratio χ on the above factors.
Birefringent optical retarders from laser 3D-printed dielectric metasurfaces
Authors: Varapnickas Simonas , Chandran Thodika Samlan , Moroté Fabien , Juodkazis Saulius , Malinauskas Mangirdas , Brasselet Etienne
Published: April 2021

Structuring light attracts continuous research effort due to its impactful applications in optical information and communications, laser material processing, optical imaging, or optical manipulation of matter. In particular, femtosecond laser direct writing of photoresists is a technology dedicated to the creation of optically isotropic free-form 3D micro-optical elements with size, spatial resolution, and surface quality that qualify to demanding integrated optics needs. Here, we report on the design, production, and characterization of dielectric metasurface birefringent optical retarders made from femtosecond laser 3D printing technology whose polarization conversion efficiency is more than 10 times larger than that previously reported Wang et al., Appl. Phys. Lett. 110, 181101 (2017)]. As the flexibility of the fabrication process allows considering arbitrary orientation of the artificially engineered optical axis, these results open up for 3D printed geometric phase optical elements.
Switching the fracture toughness of single-crystal ZnS using light irradiation
Authors: Zhu Tingting , Ding Kuan , Oshima Yu , Amiri Anahid , Bruder Enrico , Stark Robert W. , Durst Karsten , Matsunaga Katsuyuki , Nakamura Atsutomo , Fang Xufei
Published: April 2021

An enormous change in the dislocation-mediated plasticity has been found in a bulk semiconductor that exhibits the photoplastic effect. Herein, we report that UV (365 nm) light irradiation during mechanical testing dramatically decreases the fracture toughness of ZnS. The crack tip toughness on a (001) single-crystal ZnS, as measured by the near-tip crack opening displacement method, is increased by ∼45% in complete darkness compared to that in UV light. The increase in fracture toughness is attributed to a significant increase in the dislocation mobility in darkness, as explained by the crack tip dislocation shielding model. Our finding suggests a route toward controlling the fracture toughness of photoplastic semiconductors by tuning the light irradiation.
Can flexible timing of harvest for translocation reduce the impact on fluctuating source populations?
Authors: Verdon Simon J. , Mitchell William F. , Clarke Michael F.
Published: April 2021

Abstract Context Species translocations are used in conservation globally. Although harvest for translocation may have negative impacts on source populations, translocation programs rarely explore ways of minimising those impacts. In fluctuating source populations, harvest timing may affect its impact because population size and trajectory vary among years. Aims We explored whether the timing and scale of harvest can be altered to reduce its impact on a fluctuating source population of Mallee Emu-wrens, Stipiturus mallee; an endangered passerine in south-eastern Australia. Mallee Emu-wren populations fluctuate with ~5–10-year drought–rain cycles. Methods We used population viability analysis (PVA) to compare the impact of five harvest scales (no harvest, 100, 200, 300 or 500 individuals) under three population trajectories (increasing, stable or decreasing) and two initial population sizes (our model-based estimate of the population size and the lower 95% confidence interval of that estimate). To generate a model-based estimate of the population size, we surveyed 540 sites (9 ha), stratified according to environmental variables known to affect Mallee Emu-wren occurrence. We used an information-theoretic approach with N-mixture models to estimate Mallee Emu-wren density, and extrapolated results over all potential habitat. Key Results We estimate that in spring 2019, the source population consisted of 6449 individuals, with a minimum of 1923 individuals (lower 95% confidence interval). Of 48 harvest scenarios, only seven showed no impact of harvest within 5 years (15%). Those seven all had increasing population trajectories and carrying capacity set to equal initial population size. Twenty-six populations showed no impact of harvest within 25 years (54%). These were either increasing populations that had reached carrying capacity or decreasing populations nearing extinction. Conclusions Initial population size, carrying capacity, harvest scale and population trajectory were all determinants of harvest impact. Given the importance of carrying capacity, further research is required to determine its role in the Mallee Emu-wren source population. Implications Harvesting Mallee Emu-wrens after high-rainfall years will have the least impact because source populations are likely to be large with increasing trajectories. For fluctuating source populations, flexibility in the timing of harvest can reduce its impact and should be considered during translocation planning.
Single-cell visualization and quantification of trace metals inChlamydomonaslysosome-related organelles
Authors: Schmollinger Stefan , Chen Si , Strenkert Daniela , Hui Colleen , Ralle Martina , Merchant Sabeeha S.
Published: April 2021

Significance

Transition metals are of crucial importance for primary productivity; their scarcity limits crop yield in agriculture and carbon sequestration on a global scale. Copper (Cu), iron (Fe), and manganese (Mn) are among the most important trace elements that enable the redox chemistry in oxygenic photosynthesis. The single-celled, eukaryotic green algaChlamydomonas reinhardtiiis a choice experimental system for studying trace metal homeostasis in the context of phototrophy, offering all the advantages of a classical microbial system with a well-characterized photosystem and trace metal metabolism machinery of relevance to plants. This project identifies and differentiates different trace metal storage sites inChlamydomonasand uncovers the dynamics of trace metal storage and mobilization in situations of fluctuating resources.
Specific modulation of the root immune system by a community of commensal bacteria
Authors: Teixeira Paulo J. P. L. , Colaianni Nicholas R. , Law Theresa F. , Conway Jonathan M. , Gilbert Sarah , Li Haofan , Salas-González Isai , Panda Darshana , Del Risco Nicole M. , Finkel Omri M. , Castrillo Gabriel , Mieczkowski Piotr , Jones Corbin D. , Dangl Jeffery L.
Published: April 2021

Significance

In natural environments, plants establish intimate interactions with a wide diversity of microbes. It is unknown, however, how microbiota composed of commensal bacteria colonize roots in the face of a sophisticated plant immune system that evolved to recognize microbial-associated molecular patterns. We investigate the interaction between plant immune system function and the root microbiota. We report that root-associated commensal bacteria actively suppress the host immune response in the context of a community. Suppressors and nonsuppressors co-occur in the root microbiome and the presence of the former can enhance the colonization ability of the latter. We highlight the role of a specific sector of the plant immune system and its suppression in gating microbial access to the roots.
Maize chlorotic mottle virus.
Authors: Scheets Kay
Published: April 2021

In Peru, losses in floury and sweet maize varieties due to MCMV have been reported to average between 10 and 15%. In experimental plots, inoculated plant yields were reduced by up to 59% (Castillo, 1976). In Kansas crop losses due to corn lethal necrosis (caused by MCMV and any potyvirus) have been estimated to be between 50 (Uyemoto et al., 1980) and 90% (Niblett and Claflin, 1978) depending on the variety of maize and the year.
Ficus lyrata (fiddle-leaf fig).
Authors: Datiles Marianne Jennifer , Acevedo-Rodrígue Pedro
Published: April 2021

A datasheet on Ficus lyrata covering, as an economically important tree, its taxonomy, importance, silviculture, distribution, biology and ecology, uses, products and pests.
Morinda citrifolia (Indian mulberry).
Authors: Rojas-Sandoval Julissa
Published: April 2021

A datasheet on Morinda citrifolia covering, as an economically important tree, its taxonomy, importance, silviculture, distribution, biology and ecology, uses, products and pests.
Pachira insignis (wild chestnut).
Authors: Areces-Berazain Fabiola
Published: April 2021

A datasheet on Pachira insignis covering, as an economically important tree, its taxonomy, importance, silviculture, distribution, biology and ecology, uses, products and pests.
Phyllostachys aureosulcata (yellow groove bamboo).
Authors: Rickel Caryn
Published: April 2021

A datasheet on Phyllostachys aureosulcata covering, as an economically important bamboo or rattan, its taxonomy, importance, cultivation, distribution, biology and ecology, uses, products and pests.
Pimenta racemosa (bay rum tree).
Authors: Pasiecznik Nick
Published: April 2021

A datasheet on Pimenta racemosa covering, as an economically important tree, its taxonomy, importance, silviculture, distribution, biology and ecology, uses, products and pests.
Ptychosperma macarthurii (MacArthur palm).
Authors: Rojas-Sandoval Julissa , Acevedo-Rodrígue Pedro
Published: April 2021

A datasheet on Ptychosperma macarthurii covering, as an economically important tree, its taxonomy, importance, silviculture, distribution, biology and ecology, uses, products and pests.
Tecoma capensis (Cape honeysuckle).
Authors: Rojas-Sandoval Julissa
Published: April 2021

A datasheet on Tecoma capensis covering, as an economically important tree, its taxonomy, importance, silviculture, distribution, biology and ecology, uses, products and pests.
Parkin-independent mitophagy via Drp1-mediated outer membrane severing and inner membrane ubiquitination
Authors: Oshima Yumiko , Cartier Etienne , Boyman Liron , Verhoeven Nicolas , Polster Brian M. , Huang Weiliang , Kane Maureen , Lederer W. Jonathan , Karbowski Mariusz
Published: April 2021

Here, we report that acute reduction in mitochondrial translation fidelity (MTF) causes ubiquitination of the inner mitochondrial membrane (IMM) proteins, including TRAP1 and CPOX, which occurs selectively in mitochondria with a severed outer mitochondrial membrane (OMM). Ubiquitinated IMM recruits the autophagy machinery. Inhibiting autophagy leads to increased accumulation of mitochondria with severed OMM and ubiquitinated IMM. This process occurs downstream of the accumulation of cytochrome c/CPOX in a subset of mitochondria heterogeneously distributed throughout the cell (“mosaic distribution”). Formation of mosaic mitochondria, OMM severing, and IMM ubiquitination require active mitochondrial translation and mitochondrial fission, but not the proapoptotic proteins Bax and Bak. In contrast, in Parkin-overexpressing cells, MTF reduction does not lead to the severing of the OMM or IMM ubiquitination, but it does induce Drp1-independent ubiquitination of the OMM. Furthermore, high–cytochrome c/CPOX mitochondria are preferentially targeted by Parkin, indicating that in the context of reduced MTF, they are mitophagy intermediates regardless of Parkin expression. In sum, Parkin-deficient cells adapt to mitochondrial proteotoxicity through a Drp1-mediated mechanism that involves the severing of the OMM and autophagy targeting ubiquitinated IMM proteins.
Aurora B switches relative strength of kinetochore–microtubule attachment modes for error correction
Authors: Doodhi Harinath , Kasciukovic Taciana , Clayton Lesley , Tanaka Tomoyuki U.
Published: April 2021

To establish chromosome biorientation, aberrant kinetochore–microtubule interaction must be resolved (error correction) by Aurora B kinase. Aurora B differentially regulates kinetochore attachment to the microtubule plus end and its lateral side (end-on and lateral attachment, respectively). However, it is still unclear how kinetochore–microtubule interactions are exchanged during error correction. Here, we reconstituted the budding yeast kinetochore–microtubule interface in vitro by attaching the Ndc80 complexes to nanobeads. These Ndc80C nanobeads recapitulated in vitro the lateral and end-on attachments of authentic kinetochores on dynamic microtubules loaded with the Dam1 complex. This in vitro assay enabled the direct comparison of lateral and end-on attachment strength and showed that Dam1 phosphorylation by Aurora B makes the end-on attachment weaker than the lateral attachment. Similar reconstitutions with purified kinetochore particles were used for comparison. We suggest the Dam1 phosphorylation weakens interaction with the Ndc80 complex, disrupts the end-on attachment, and promotes the exchange to a new lateral attachment, leading to error correction.
Influence of asymmetric surface screening conditions on vortex switching in a ferroelectric nanodot
Authors: Xiong P C , Yuan S , Liu Y L , Wang B
Published: April 2021

The behaviors of vortex switching in a ferroelectric nanodot on different surface screening conditions are investigated by phase-field simulations. It is found that asymmetric electrical boundary conditions have a significant effect on the formation of vortex domain structures and play a deterministic role in manipulating the vortex chirality by a homogeneous electrostatic field. The results indicate that the critical electric field for vortex switching can be greatly reduced by engineering the asymmetric surface screening conditions in a ferroelectric nanodot with a regular structure and uniform composition.
Excitation of near field coupled dual toroidal resonances in a bilayer terahertz metamaterial configuration
Authors: Bhattacharya Angana , Sarkar Rakesh , Kumar Gagan
Published: April 2021

We discuss the excitation of dual toroidal dipolar resonances in a bilayer terahertz metamaterial configuration and examine their near field coupling induced modulation. The study is focused on the interaction and modulation between toroidal resonances excited in two layers of a bilayer system. The rotation of the symmetric circular split ring of the top layer resonator with respect to the bottom one, causes the dual resonances to modulate and ultimately switching into a single toroidal resonance. The strong near field coupled modulation is observed when both the resonator layers are placed in close proximity. A Lagrangian approach is suggested to understand the underlying mechanism of the coupled toroidal resonances. The increase in strength of the toroidal dipolar resonance on adding two layers is suggested based upon the quality factors of the resonances. Such a study enables the design of toroidal photonics devices with high quality factors and improved light–matter interaction.
Impact of photoelectric cross section data on systematic uncertainties for Monte Carlo breast dosimetry in mammography
Authors: Massera Rodrigo T , Fernández-Varea José M , Tomal Alessandra
Published: April 2021

Monte Carlo (MC) simulations are employed extensively in breast dosimetry studies. In the energy interval of interest in mammography energy deposition is predominantly caused by the photoelectric effect, and the corresponding cross sections used by the MC codes to model this interaction process have a direct influence on the simulation results. The present work compares two photoelectric cross section databases in order to estimate the systematic uncertainty, related to breast dosimetry, introduced by the choice of cross sections for photoabsorption. The databases with and without the so-called normalization screening correction are denoted as ‘renormalized’ or ‘un-normalized’, respectively. The simulations were performed with the PENELOPE/penEasy code system, for a geometry resembling a mammography examination. The mean glandular dose (MGD), incident air kerma (K
air), normalized glandular dose (DgN) and glandular depth-dose (GDD(z)) were scored, for homogeneous breast phantoms, using both databases. The AAPM Report TG-195 case 3 was replicated, and the results were included. Moreover, cases with heterogeneous and anthropomorphic breast phantoms were also addressed. The results simulated with the un-normalized cross sections are in better overall agreement with the TG-195 data than those from the renormalized cross sections; for MGD the largest discrepancies are 0.13(6)% and 0.74(5)%, respectively. The MGD, K
air and DgN values simulated with the two databases show differences that diminish from approximately 10%/3%/6.8% at 8.25 keV down to 1.5%/1.7%/0.4% at 48.75 keV, respectively. For polyenergetic spectra, deviations up to 2.5% were observed. The disagreement between the GDDs simulated with the analyzed databases increases with depth, ranging from −1% near the breast entrance to 4% near the bottom. Thus, the choice of photoelectric cross section database affects the MC simulation results of breast dosimetry and adds a non-negligible systematic uncertainty to the dosimetric quantities used in mammography.
Interfacial magnetic coupling and orbital hybridization for D022-Mn3Ga/Fe films
Authors: Zhang Fengyuan , Tong Junwei , Wu Yanzhao , Liu Guohui , Zhang Rui , Tian Fubo , Qin Gaowu , Zhang Xianmin
Published: April 2021

Interfacial magnetic coupling interactions between D022-Mn3Ga and ultrathin Fe films were studied using first principles calculations. Based on the calculations of surface energy and interface energy, it is demonstrated that Mn-Ga/Fe is the most stable interfacial structure. As a result, four possible coupling states between D022-Mn3Ga and Fe films may be present by considering the relative direction of magnetic moment for the interfacial and inner-layer Mn atoms. Their corresponding energies were calculated by varying the Fe atomic layer thicknesses from 1 to 6 monolayers. It is found that the antiferromagnetic coupling energy in D022-Mn3Ga/Fe films with an anti-parallel magnetic moment of the interfacial and inner-layer Mn atoms is the smallest one, regardless of the Fe layer numbers. The possible mechanism about the antiferromagnetic interactions between D022-Mn3Ga and ultrathin Fe films was analyzed by the orbital-resolved electronic density of states.
The trans-Planckian problem in tachyacoustic cosmology
Authors: Lin Wei-Chen , Kinney William H.
Published: April 2021

We study Tachyacoustic models of cosmology, for which a scale-invariant perturbation spectrum is generated via superluminal sound speed instead of accelerated expansion, as in the case of inflation. We derive two bounds on the size of acoustic horizon which constrain the duration of tachyacoustic evolution, and therefore generation of primordial perturbations. We show that existing models cannot solve the horizon problem without violating the condition that all physical scales — such as the Hubble parameter, the pressure, and the length scale at which quantum modes freeze out and become classical — be sub-Planckian.
Cosmic ray propagation in the Universe in presence of a random magnetic field
Authors: Supanitsky A.D.
Published: April 2021

The origin of the ultrahigh energy cosmic ray remains being a mystery. However, a
considerable progress has been made in the past few years due to the good quality data recorded
by current cosmic ray observatories. One of the recent achievements is obtaining firm observational
evidence about the extragalactic origin of the most energetic cosmic rays by the Pierre Auger
observatory. On the other hand, it is believed that there is a non-null turbulent magnetic field
that fills the intergalactic medium. Therefore, the presence of the intergalactic magnetic field
can play an important role on the propagation of the ultrahigh energy cosmic rays through the
Universe, which in principle can be relevant to interpret the experimental data. In this work we
present a system of partial differential equations that describes the propagation of the ultrahigh
energy cosmic rays through the Universe, in the presence of a turbulent intergalactic magnetic field,
that includes the diffusive and the ballistic regime of propagation and also the transition between
them. Also, as an example of application, the system of equations is solved numerically in a
simplified physical situation.
Dosimetric analysis of cervical cancer stage IIB patients treated with volumetric modulated arc therapy using plan uncertainty parameters module of Varian Eclipse treatment planning system
Authors: Singh Gaganpreet , Tyagi Atul , Thaper Deepak , Kamal Rose , Kumar Vivek , Oinam Arun S , Srivastava Ranjana , Halder Shikha , Hukku Shelly
Published: April 2021

Introduction. The present study aims to investigate the dosimetric and radiobiological impact of patient setup errors (PSE) on the target and organs at risk (OAR) of the cervix carcinoma stage IIB patients treated with volumetric-modulated arc therapy (VMAT) delivery technique using plan uncertainty parameters module of Varian Eclipse treatment planning system and in-house developed DVH Analyzer program. Materials and Methods. A total of 976 VMAT plans were generated to simulate the PSE in the base plan that varies from −10 mm to 10 mm in a step size of 1 mm in x– (lateral), y– (craniocaudal), and z– (anteroposterior) directions. The different OAR and tumor (PTV) volumes were delineated in each case. Various plan quality metrics, such as conformity index (CI) and homogeneity index (HI), as well as radiobiological quantities, such as tumor control probability (TCP) and normal tissue control probability (NTCP), were calculated from the DVH bands generated from the cohort of treatment plans associated with each patient case, using an in-house developed ‘DVH Analyzer’ program. The extracted parameters were statistically analyzed and compared with the base plan’s dosimetric parameters having no PSE. Results. The maximum variation of (i) 2.4%, 21.5%, 0.8%, 2.5% in D2cc of bladder, rectum, small bowel and sigmoid colon respectively; (ii) 19.3% and 18.9% in Dmax of the left and right femoral heads (iii) 16.9% in D95% of PTV (iv) 12.1% in NTCP of sigmoid colon were observed with change of PSE in all directions. TCP was found to be considerably affected for PSEs larger than 4 mm in x+, y+, z+ directions and 7 mm in x-, y- and z- directions, respectively. Conclusion. This study presents the effect of PSE on TCP and NTCP for the cervix carcinoma cases treated with VMAT technique and also recommends daily image guidance to mitigate the effects of PSE.
Prediction of the transverse elastic modulus of the unidirectional composites by an artificial neural network with fiber positions and volume fraction
Authors: Kim Do-Won , Park Shin-Mu , Lim Jae Hyuk
Published: April 2021

This paper presents the development of artificial neural network (ANN) modeling for predicting the transverse elastic modulus of a unidirectional composite (E-glass/MY750) with fiber positions and volume fraction. For this prediction, random representative volume elements were generated according to the fiber volume fraction (

V

f

). A training dataset consisting of input data (

V

f

and fiber locations) and output data (the effective elastic modulus), which were computed by the computational homogenization scheme (CHS), was used to train the ANN model to have proper weight and bias by back propagation. To demonstrate the performance of the proposed ANN model, prediction of the transverse elastic modulus of various test datasets whose transverse elastic moduli are known by CHS was conducted. The prediction accuracy was verified in terms of the mean squared error, correlation coefficient (R), and relative error. The prediction results showed excellent agreement with the test dataset and quickly predicted the transverse elastic modulus having random microstructures.
Analysis of laminar flow and heat transfer characteristics of fluid in plain and induced tubes
Authors: Oluwasesan Oni Taiwo
Published: April 2021

Heat energy is applied in various equipment and the pursuit to produce equipment that has an improved performance is increasing. In pursuit to augment heat transfer in such equipment for its better performance, it is necessary to induce the tubes of the equipment by integration of supplementary devices into them or modification of their geometries, and then analyse thermo-hydraulic characteristics of flow in the tubes. In this work, thermo-hydraulic characteristics of laminar flow in eight different tube models were numerically analysed. The models comprise tube without a tape inside it (Tube-P), plain-twisted-tape-induced tube (Tube-L), ellipse-shaped-opening-twisted-tape-induced tube (Tube-E), circle-shaped-opening-twisted-tape-induced tube (Tube-C), triangle-shaped-opening-twisted-tape-induced tube (Tube-T), intersected-axes-ellipse-shaped-opening-twisted-tape-induced tube (Tube-EX), intersected-axes-circle-shaped-opening-twisted-tape-induced tube (Tube-CX), and intersected-axes-triangle-shaped-opening-twisted-tape-induced tube (Tube-TX). The goal of the current work focuses on identifying the model among them whose performance is the most superior. Reynolds numbers of values between 830 and 2,000 were assigned to the laminar flow, and a CFD software known as Fluent was used to carry out the simulation of the thermo-hydraulic characteristics of the laminar flow. The findings revealed that the intersected axes and the geometry of the openings in the tapes have impacts on the models’ performance. The Tube-TX model’s performance is the most superior among all the models as its Nusselt number is 64.70 to 103.22% more than that in the Tube-L model. The friction factor in the Tube-TX model is 1.59 to 1.62 times the values in the Tube-L model. The heat transfer enhancement index of the Tube-TX model is 64.70 to 103.22% higher than that of the Tube-L model. The Nusselt number and friction factor obtained from the novel correlations formed in the current work and those obtained from the current work’s simulation are in accord with a variation of 4.08% and 1.10%, respectively.
On the switching current and the re-trapping current of tungsten nanowires fabricated by Focussed Ion Beam (FIB) technique
Authors: Kumar Abhishek , Husale Sudhir , Pandey Himanshu , Yadav Mahesh Gaurav , Yousuf Majid , Papanai Girija Shankar , Gupta Anurag , Aloysius R P
Published: April 2021

We report the superconducting properties of the tungsten (W) nanowires fabricated using focussed ion beam (FIB) technique having different wire widths of ∼120 nm and ∼290 nm. The transport properties of these wires were measured down to a temperature of 20 mK in a dilution refrigerator. We observed hysteretic current- voltage characteristics (IVCs) as a function of temperature, wherein the extend of hysteresis (difference between switching current and re-trapping current) is larger at lower temperature and diminishes near to the transition temperature. The temperature dependence of the switching current and re-trapping current were analysed using conventional models and found out to be of reasonable agreement with the models invoked. The re-trapping current agrees well with the thermal model incorporating phonon contribution in the heat dissipation process along with the electronic contribution. The equilibrium electron temperature calculated using the heat dissipation models at the critical current of the wires agrees well with respect to the transition temperature of the wire having a larger width, while for the wire of lower width, it is slightly elevated. Based on the analysis, it is believed that heat dissipation primarily because of Joule heating is the cause of the hysteretic current voltage characteristics of the nanowires.
Fabrication and characterization of lead sulfide and multi-walled carbon nanotube based field effect transistors using low cost chemical route
Authors: Patil Ganesh C , Ingle Suyog T , Sankapal Babasaheb R
Published: April 2021

In this paper, lead sulfide (PbS) and multi-walled carbon nanotube (MWCNT) based field effect transistors (FETs) have been fabricated by using simple and low cost solution processing. The fabricated devices having channel length of 3 mm have been functionalized as a n-channel FETs. It has been observed from the output and the transfer characterstics that at the gate-to-source voltage (V
GS) of 15 V and drain-to-source voltage (V
DS) of 10 V, the on-state-drive current (I
ON) for PbS and MWCNT based FETs is 42.23 μA and 25.52 μA, respectively, whereas at V
GS = 0 V and V
DS = 10 V the off-state leakage current (I
OFF) is 0.183 μA and 0.11 μA, respectively. Further, for PbS and MWCNT based FETs at the measured threshold voltage of 5.75 V and 6.3 V, the sub-threshold swing is found to be 5.23 V/Decade and 6.12 V/Decade, respectively. The morphological and structural studies have been performed to speculate the crystallinity and the topography of the individual layers. The chemical composition of the different layers clearly justify the deposition of the material layers in the fabricated FETs. In addtion, this work also proposes a new approach for fabricating the PbS and MWCNT based FETs.
Pharmacometabonomics: data processing and statistical analysis
Authors: Fu Jianbo , Zhang Ying , Liu Jin , Lian Xichen , Tang Jing , Zhu Feng
Published: April 2021

Individual variations in drug efficacy, side effects and adverse drug reactions are still challenging that cannot be ignored in drug research and development. The aim of pharmacometabonomics is to better understand the pharmacokinetic properties of drugs and monitor the drug effects on specific metabolic pathways. Here, we systematically reviewed the recent technological advances in pharmacometabonomics for better understanding the pathophysiological mechanisms of diseases as well as the metabolic effects of drugs on bodies. First, the advantages and disadvantages of all mainstream analytical techniques were compared. Second, many data processing strategies including filtering, missing value imputation, quality control-based correction, transformation, normalization together with the methods implemented in each step were discussed. Third, various feature selection and feature extraction algorithms commonly applied in pharmacometabonomics were described. Finally, the databases that facilitate current pharmacometabonomics were collected and discussed. All in all, this review provided guidance for researchers engaged in pharmacometabonomics and metabolomics, and it would promote the wide application of metabolomics in drug research and personalized medicine.
Variability and the primacy of the genotype
Authors: Wilkens Horst
Published: April 2021

Cave animals and species flocks exhibit common evolutionary principles. In caves, all traits dependent on the information derived from light lose their biological function. Mutations destructive for such traits, but neutral for the organism as a whole, can persist and accumulate until a trait has vanished. Adaptive radiations start in ecosystems containing open niches. Here, selection on niche-specific traits, such as the viscerocranium in fish, is relaxed owing to the absence of competing species, and viscerocranial variability arises. It is transitorily high in recent and phylogenetically younger flocks, providing new phenotypes. It lessens and is completely lost after directional selection promotes the fixation of phenotypes that are best adapted. In cave animals and species flocks, single traits manifest phenotypic variability owing to relaxed selection. Like the eye in cave species, the viscerocranium can be classified a module, the development of which is encoded in gene regulatory networks. Mutations in these genes can result in new phenotypes. Regarding functionality, these mutations might be destructive and eliminated by selection, neutral and thus persisting, or beneficial and promoted to fixation by directional selection. Given the ancient heritage of teleostean fish, these gene regulatory networks might be prone to mutations at the same loci or to developmental reactions resulting in similar phenotypes in closely related or taxonomically and geographically distant species.
Defining functional variants associated with Alzheimer’s disease in the induced immune response
Authors: Harwood Janet C , Leonenko Ganna , Sims Rebecca , Escott-Price Valentina , Williams Julie , Holmans Peter
Published: April 2021

Defining the mechanisms involved in the aetiology of Alzheimer’s disease from genome-wide association studies alone is challenging since Alzheimer’s disease is polygenic and most genetic variants are non-coding. Non-coding Alzheimer’s disease risk variants can influence gene expression by affecting miRNA binding and those located within enhancers and within CTCF sites may influence gene expression through alterations in chromatin states. In addition, their function can be cell-type specific. They can function specifically in microglial enhancers thus affecting gene expression in the brain. Hence, transcriptome-wide association studies have been applied to test the genetic association between disease risk and cell-/tissue-specific gene expression. Many Alzheimer’s disease-associated loci are involved in the pathways of the innate immune system. Both microglia, the primary immune cells of the brain, and monocytes which can infiltrate the brain and differentiate into activated macrophages, have roles in neuroinflammation and β-amyloid clearance through phagocytosis. In monocytes the function of regulatory variants can be context-specific after immune stimulation. To dissect the variants associated with Alzheimer’s disease in the context of monocytes, we utilized data from naïve monocytes and following immune stimulation in vitro, in combination with genome-wide association studies of Alzheimer’s disease in transcriptome-wide association studies. Of the nine genes with statistically independent transcriptome-wide association signals, seven are located in known Alzheimer’s disease risk loci: BIN1, PTK2B, SPI1, MS4A4A, MS4A6E, APOE and PVR. The transcriptome-wide association signal for MS4A6E, PTK2B and PVR and the direction of effect replicated in an independent genome-wide association studies. Our analysis identified two novel candidate genes for Alzheimer’s disease risk, LACTB2 and PLIN2/ADRP. LACTB2 replicated in a transcriptome-wide association study using independent expression weights. LACTB2 and PLIN2/ADRP are involved in mitochondrial function and lipid metabolism, respectively. Comparison of transcriptome-wide association study results from monocytes, whole blood and brain showed that the signal for PTK2B is specific to blood and MS4A6E is specific to LPS stimulated monocytes.
How Well Do Laboratories Adhere to Recommended Guidelines for Cardiac Biomarkers Management in Europe? The CArdiac MARker Guideline Uptake in Europe (CAMARGUE) Study of the European Federation of Laboratory Medicine Task Group on Cardiac Markers
Authors: Collinson Paul , Suvisaari Janne , Aakre Kristin M , Baum Hannsjörg , Duff Christopher J , Gruson Damien , Hammerer-Lercher Angelika , Pulkki Kari , Stankovic Sanja , Langlois Michel R , Apple Fred S , Laitinen Päivi ,   for the EFLM Task Group on Cardiac Markers
Published: April 2021

Background

The CARdiac MARker Guideline Uptake in Europe (CAMARGUE) program is a multi-country audit of the use of cardiac biomarkers in routine clinical practice.

Methods

An email link to a web-based questionnaire of 30 multiple-choice questions was distributed via the professional societies in Europe.

Results

374 questionnaires were returned from 39 countries, the majority of which were in northern Europe with a response rate of 8.2%–42.0%. The majority of the respondents were from hospitals with proportionately more responses from central hospitals than district hospitals. Cardiac troponin was the preferred cardiac biomarker, evenly split between cardiac troponin T (cTnT) and cardiac troponin I (cTnI). Aspartate transaminase and lactate dehydrogenase are no longer offered as cardiac biomarkers. Creatine kinase, creatine kinase MB isoenzyme, and myoglobin continue to be offered as part of the cardiac biomarker profile in approximately on 50% of respondents. There is widespread utilization of high sensitivity (hs) troponin assays. The majority of cTnT users measure hs-cTnT. 29.5% of laboratories measure cTnI by a non-hs method but there has been substantial conversion to hs-cTnI. The majority of respondents used ng/L and use the 99th percentile as the upper reference limit (71.9% of respondents). A range of diagnostic protocols are in use.

Conclusions

There is widespread utilization of hs troponin methods. A significant minority do not use the 99th percentile as recommended and there is, as yet, little uptake of very rapid diagnostic strategies. Education of laboratory professionals and clinicians remains a priority.
Cell therapy in patients with heart failure: a comprehensive review and emerging concepts
Authors: Bolli Roberto , Solankhi Mitesh , Tang Xiang-Liang , Kahlon Arunpreet
Published: April 2021

This review summarizes the results of clinical trials of cell therapy in patients with heart failure (HF). In contrast to acute myocardial infarction (where results have been consistently negative for more than a decade), in the setting of HF the results of Phase I–II trials are encouraging, both in ischaemic and non-ischaemic cardiomyopathy. Several well-designed Phase II studies have met their primary endpoint and demonstrated an efficacy signal, which is remarkable considering that only one dose of cells was used. That an efficacy signal was seen 6–12 months after a single treatment provides a rationale for larger, rigorous trials. Importantly, no safety concerns have emerged. Amongst the various cell types tested, mesenchymal stromal cells derived from bone marrow (BM), umbilical cord, or adipose tissue show the greatest promise. In contrast, embryonic stem cells are not likely to become a clinical therapy. Unfractionated BM cells and cardiosphere-derived cells have been abandoned. The cell products used for HF will most likely be allogeneic. New approaches, such as repeated cell treatment and intravenous delivery, may revolutionize the field. As is the case for most new therapies, the development of cell therapies for HF has been slow, plagued by multifarious problems, and punctuated by many setbacks; at present, the utility of cell therapy in HF remains to be determined. What the field needs is rigorous, well-designed Phase III trials. The most important things to move forward are to keep an open mind, avoid preconceived notions, and let ourselves be guided by the evidence.
STING, a cytosolic DNA sensor, plays a critical role in atherogenesis: a link between innate immunity and chronic inflammation caused by lifestyle-related diseases
Authors: Pham Phuong Tran , Fukuda Daiju , Nishimoto Sachiko , Kim-Kaneyama Joo-Ri , Lei Xiao-Feng , Takahashi Yutaka , Sato Tomohito , Tanaka Kimie , Suto Kumiko , Kawabata Yutaka , Yamaguchi Koji , Yagi Shusuke , Kusunose Kenya , Yamada Hirotsugu , Soeki Takeshi , Wakatsuki Tetsuzo , Shimada Kenji , Kanematsu Yasuhisa , Takagi Yasushi , Shimabukuro Michio , Setou Mitsutoshi , Barber Glen N , Sata Masataka
Published: April 2021

Aims

Lifestyle-related diseases promote atherosclerosis, a chronic inflammatory disease; however, the molecular mechanism remains largely unknown. Endogenous DNA fragments released under over-nutrient condition provoke sterile inflammation through the recognition by DNA sensors. Here, we investigated the role of stimulator of interferon genes (STING), a cytosolic DNA sensor, in atherogenesis.

Methods and results

Apolipoprotein E-deficient (Apoe−/−) mice fed a western-type diet (WTD), a hypercholesterolaemic mouse model, showed higher STING expression and markers for DNA damage such as γH2AX, p53, and single-stranded DNA (ssDNA) accumulation in macrophages in the aorta compared with wild-type (WT) mice. The level of cGAMP, a STING agonist, in the aorta was higher in Apoe−/− mice. Genetic deletion of Sting in Apoe−/− mice reduced atherosclerotic lesions in the aortic arch, lipid, and macrophage accumulation in plaques, and inflammatory molecule expression in the aorta compared with the control. Pharmacological blockade of STING using a specific inhibitor, C-176, ameliorated atherogenesis in Apoe−/− mice. In contrast, bone marrow-specific STING expression in Apoe−/− mice stimulated atherogenesis. Expression or deletion of STING did not affect metabolic parameters and blood pressure. In vitro studies revealed that STING activation by cGAMP or mitochondrial DNA accelerated inflammatory molecule expression (e.g. TNF-α or IFN-β) in mouse and human macrophages. Activation of nuclear factor-κB and TANK binding kinase 1 was involved in STING-associated vascular inflammation and macrophage activation. Furthermore, human atherosclerotic lesions in the carotid arteries expressed STING and cGAMP.

Conclusion

Stimulator of interferon genes stimulates pro-inflammatory activation of macrophages, leading to the development of atherosclerosis. Stimulator of interferon genes signalling may serve as a potential therapeutic target for atherosclerosis.
Non-canonical substrates for terpene synthases in bacteria are synthesized by a new family of methyltransferases
Authors: Piechulla Birgit , Zhang Chi , Eisenschmidt-Bönn Daniela , Chen Feng , Magnus Nancy
Published: April 2021

The ‘biogenetic isoprene rule’, formulated in the mid 20th century, predicted that terpenoids are biosynthesized via polymerization of C5 isoprene units. The polymerizing enzymes have been identified to be isoprenyl diphosphate synthases, products of which are catalyzed by terpene synthases (TPSs) to achieve vast structural diversity of terpene skeletons. Irregular terpenes (e.g, C11, C12, C16 and C17) are also frequently observed, and they have presumed to be synthesized by the modification of terpene skeletons. This review highlights the exciting discovery of an additional route to the biosynthesis of irregular terpenes which involves the action of a newly discovered enzyme family of isoprenyl diphosphate methyltransferases (IDMTs). These enzymes methylate, and sometimes cyclize, the classical isoprenyl diphosphate substrates to produce modified, non-canonical substrates for specifically evolved TPSs. So far, this new pathway has been found only in bacteria. Structure and sequence comparisons of the IDMTs strongly indicate a conservation of their active pockets and overall topologies. Some bacterial IDMTs and TPSs appear in small gene clusters, which may facilitate future mining of bacterial genomes for identification of irregular terpene-producing enzymes. The IDMT-TPS route for terpenoid biosynthesis presents another example of nature's ingenuity in creating chemical diversity, particularly terpenoids, for organismal fitness.
Galerkin finite element approximation of a stochastic semilinear fractional subdiffusion with fractionally integrated additive noise
Authors: Kang Wenyan , Egwu Bernard A , Yan Yubin , Pani Amiya K
Published: April 2021

A Galerkin finite element method is applied to approximate the solution of a semilinear stochastic space and time fractional subdiffusion problem with the Caputo fractional derivative of the order $ \alpha \in (0, 1)$, driven by fractionally integrated additive noise. After discussing the existence, uniqueness and regularity results, we approximate the noise with the piecewise constant function in time, in order to obtain a regularized stochastic fractional subdiffusion problem. The regularized problem is then approximated by using the finite element method in spatial direction. The mean squared errors are proved based on the sharp estimates of the various Mittag–Leffler functions involved in the integrals. Numerical experiments are conducted to show that the numerical results are consistent with the theoretical findings.
On the Weyl Problem in Minkowski Space
Authors: Smith Graham
Published: April 2021

Let $S$ be a closed surface of hyperbolic type. We show that, for every pair $(g_+,g_-)$ of negatively curved metrics over $S$, there exists a unique globally hyperbolic, maximal, and Cauchy compact Minkowski spacetime $X$ into which $(S,g_+)$ and $(S,g_-)$ isometrically embed as Cauchy surfaces in the future and past components, respectively.