bluuebunny/crossref_metadata_2025_split huggingface dataset:
Inoculum effect of antimicrobial peptides
Authors: Loffredo Maria Rosa , Savini Filippo , Bobone Sara , Casciaro Bruno , Franzyk Henrik , Mangoni Maria Luisa , Stella Lorenzo 
Published: May 2021

SignificanceBacterial drug resistance is a crucial threat to global health, and antimicrobials with novel mechanisms of action are urgently needed. Antimicrobial peptides are natural molecules that kill bacteria mostly by perturbing their membranes, and they constitute promising compounds for fighting resistant microbes. Their activity is normally tested under standardized conditions of bacterial density. However, the bacterial load in clinically relevant infections varies by many orders of magnitude. Here, we show that the minimum peptide concentration needed for bacterial growth inhibition can vary by more than 100-fold with an increase in the density of cells in the initial inoculum of the assay (a phenomenon termed the “inoculum effect”). These findings question the utility of the currently used activity screening assays.
Flexoelectricity in soft elastomers and the molecular mechanisms underpinning the design and emergence of giant flexoelectricity
Authors: Grasinger Matthew , Mozaffari Kosar , Sharma Pradeep 
Published: May 2021

Significance
The molecular-scale phenomena that lead to the emergence of the flexoelectric effect in elastomers are not well understood. We present a molecular-to-continuum scale theory and show it to be valid for common types of elastomers. We unravel a mechanism for achieving giant flexoelectricity—which finds support in prior experimental results. The multiscale theory is then leveraged for material design and we propose specific modalities for 1) the emergence of piezoelectricity, 2) tuning the direction of flexoelectricity, and 3) flexoelectricity which is invariant with respect to spurious deformations. These developments may pave the way for the future development of efficient soft energy harvesters, sensors, and actuators, and may prove useful for high-degree-of-freedom soft robots and artificial muscles.
Triphasia trifolia (limeberry).
Authors: Rojas-Sandoval Julissa , Acevedo-Rodríguez Pedro 
Published: May 2021

Abstract

T. trifolia is an aggressive invasive plant with the capacity to grow in sunny open areas as well as in shaded areas beneath the canopy forest (Daley et al., 2012). It is a woody shrub classified as a "weed" and included in the Global Compendium of Weeds (Randall, 2012). T. trifolia spreads by seeds that can be easily dispersed by animals, mainly by birds, facilitating the invasion of this species into native forests. Seeds have high germination rates under natural conditions and grow forming dense-spiny thickets in the understory of the forest (Clark, 2003; Daley et al., 2012). For example, vegetation surveys performed in the understory of secondary forests on the islands of St. Croix (US Virgin Islands) have showed stem counts for this species exceeding 38,000 stems per hectare (Clark, 2003).
Imperata cylindrica (cogon grass).
Authors: Parker Chris 
Published: May 2021

Abstract

I. cylindrica is a serious weed not only in crops but also in natural areas, causing serious economic and environmental damage. The ability of I. cylindrica to effectively compete for water and nutrients, spread and persist through the production of seeds and rhizomes that can survive a wide range of environmental conditions, and its allelopathic effects and pyrogenic nature, allow it to exclude native plant species and other desirable plants and dominate large areas of land.
Melinis minutiflora (molasses grass).
Authors: Rojas-Sandoval Julissa , Acevedo-Rodríguez Pedro 
Published: May 2021

Abstract

M. minutiflora is a grass which is used widely as a fodder species for livestock and for its ability to grow well on poor soils, but which is also strongly invasive. It has been introduced intentionally around the world, and also probably accidentally as a seed contaminant. It is difficult to eradicate when present, and poses a threat to agriculture and the environment. This species is highly invasive and grows forming dense mats that exclude native species, alter successional processes, reduce native tree and grass regeneration, and increase intensity and frequency of fires (Hoffmann et al., 2004).
Xanthomonas campestris pv. campestris (black rot).
Authors: Mortensen Carmen Nieves 
Published: May 2021

Abstract

Black rot is considered the most important worldwide disease of crucifers. The disease is known to exist in the cool coastal climates of northern Europe and North America but was seldom a problem there until the 1990s. Its potential for crop damage is also considered low in New Zealand, and parts of Australia. In many regions of Central and Eastern Europe, Central Asia (Kazakhstan), China, tropical and subtropical regions of Asia, Africa and South America where brassicas are common and cultivated without crop rotation, black rot is always present. Seed production in those regions is commonly associated with high levels of seedborne Xcc (Williams, 1980). Even minor, visually undetectable development of black rot may considerably increase damage to plants by soft rot caused by Erwinia carotovora, Pseudomonas spp. and other opportunistic pathogens (Djalilov et al., 1989).
Heterodera ustinovi (grass cyst nematode).
Authors: Powers Thomas 
Published: May 2021

Abstract

There is limited evidence available to suggest that H. ustinovi is invasive. The identical COI halpotypes shared between the USA and Europe most likely represent recent introductions. The small amount of genetic information from North America suggests that H. ustinovi is widespread in the south west (Arizona), midwest (Ohio) and New England states, with little genetic differentiation. H. ustinovi has not been found on any plant species in the USA other than introduced Agrostis species and in turf/golf course settings. A lot of nematodes are transported in turf from turf farms. The initial discovery on native Agrostis in the Ukraine would suggest a potential native parasite existing on a native plant species, but, there are very few of samples on which to base these comparisons.
Statistical mechanics of Floquet quantum matter: exact and emergent conservation laws
Authors: Haldar Asmi , Das Arnab 
Published: May 2021

Abstract
Equilibrium statistical mechanics rests on the assumption of chaotic dynamics of a system modulo the conservation laws of local observables: extremization of entropy immediately gives Gibbs’ ensemble (GE) for energy conserving systems and a generalized version of it (GGE) when the number of local conserved quantities is more than one. Through the last decade, statistical mechanics has been extended to describe the late-time behaviour of periodically driven (Floquet) quantum matter starting from a generic state. The structure built on the fundamental assumptions of ergodicity and identification of the relevant conservation laws in this inherently non-equilibrium setting. More recently, it has been shown that the statistical mechanics of Floquet systems has a much richer structure due to the existence of emergent conservation laws: these are approximate but stable conservation laws arising due to the drive, and are not present in the undriven system. Extensive numerical and analytical results support perpetual stability of these emergent (though approximate) conservation laws, probably even in the thermodynamic limit. This banks on the recent finding of a sharp threshold for Floquet thermalization in clean, interacting non-integrable Floquet systems. This indicates to the possibility of stable Floquet phases of matter in disorder-free systems. This review intends to give a self-contained theoretical overview of these developments for a broad physics audience. We conclude by briefly surveying the current experimental scenario.
Controlling adhesion using AC electric fields across fluid films
Authors: Perez-Martinez Carla S , Groves Timothy S , Perkin Susan 
Published: May 2021

Abstract
We demonstrate reversible and switchable actuation using AC electric fields to bring two surfaces separated by a thin film of ionic fluid in and out of adhesive contact. Using a surface force balance we apply electric fields normal to a crossed-cylinder contact and measure directly the adhesive force and surface separation with sub-molecular resolution. Taking advantage of the oscillatory structural force acting between the surfaces across the fluid, which we show to be unaffected by the AC field, we pick between the distinct (quantized) adhesive states through precise tuning of the field. This proof-of-concept indicates exquisite control of surface interactions using an external field.
Buckling without bending morphogenesis: nonlinearities, spatial confinement, and branching hierarchies
Authors: Gandikota M C , Schwarz J M 
Published: May 2021

Abstract
During morphogenesis, a featureless convex cerebellum develops folds. As it does so, the cortex thickness is thinnest at the crest (gyri) and thickest at the trough (sulci) of the folds. This observation cannot be simply explained by elastic theories of buckling. A recent minimal model explained this phenomenon by modeling the developing cortex as a growing fluid under the constraints of radially spanning elastic fibers, a plia membrane and a nongrowing sub-cortex (Engstrom et al 2019 Phys. Rev. X 8 041053). In this minimal buckling without bending morphogenesis (BWBM) model, the elastic fibers were assumed to act linearly with strain. Here, we explore how nonlinear elasticity influences shape development within BWBM. The nonlinear elasticity generates a quadratic nonlinearity in the differential equation governing the system’s shape and leads to sharper troughs and wider crests, which is an identifying characteristic of cerebellar folds at later stages in development. As developing organs are typically not in isolation, we also explore the effects of steric confinement, and observe flattening of the crests. Finally, as a paradigmatic example, we propose a hierarchical version of BWBM from which a novel mechanism of branching morphogenesis naturally emerges to qualitatively predict later stages of the morphology of the developing cerebellum.
Nonlinear electric conductivity and THz-induced charge transport in graphene
Authors: Sato Shunsuke A , Rubio Angel 
Published: May 2021

Abstract
Based on the quantum master equation approach, the nonlinear electric conductivity of graphene is investigated under static electric fields for various chemical potential shifts. The simulation results show that, as the field strength increases, the effective conductivity is firstly suppressed, reflecting the depletion of effective carriers due to the large displacement in the Brillouin zone caused by the strong field. Then, as the field strength exceeds 1 MV m−1, the effective conductivity increases, overcoming the carrier depletion via the Landau–Zener tunneling process. Based on the nonlinear behavior of the conductivity, the charge transport induced by few-cycle THz pulses is studied to elucidate the ultrafast control of electric current in matter.
Structural, surface morphology and radiation shielding properties of barium ferrite powder
Authors: Ali Atif Mossad , Issa Shams A M , Algarni H , Tekin H O , Zakaly Hesham M H , Sayed M A , Rashad M 
Published: May 2021

Abstract
In this study, Barium ferrite (BaFe12O19) was prepared in powder form using the sol-gel method. Next, structural, surface morphology, and radiation shielding properties of Barium ferrite compound were determined using experimental and simulation methods. The structural and surface morphology were characterised using x-ray diffraction (XRD) and the scanning electron microscope (SEM). The formation of hexagonal structure has been verified by XRD patterns for synthesised pure BaFe12O19. The amplitude of XRD peaks declines as the FWHM rises, indicating that crystallinity has degraded and crystallite size has decreased. SEM images provide accurate representations of surfaces. The topography of the surface is characterized by the presence of several spherical granules. Additionally, the mean diameter of the spherical granules was determined to be approximately 30 nm using the histogram. Moreover, FLUKA simulation code was used to calculate some radiation shielding parameters such as linear attenuation coefficients (4.639, 0.554, 0.336 and 0.2013 cm−1), mass attenuation coefficients (0.8787, 0.1049, 0.0686 and 0.0381 cm2 g−1), half value layers (0.1494, 1.2512, 2.0629 and 3.4434 cm) and mean free path values (0.21554, 1.8051, 2.9762and 4.9677 cm) against 0.81, 0.356, 0.911 and 2.614 MeV photon energies, respectively. The results showed that synthesized Barium ferrite has good surface renditions and distinguished spherical granules along with promising gamma-ray attenuation properties.
Universal time delay in static spherically symmetric spacetimes for null and timelike signals *
Authors: Liu Haotian , Jia Junji 
Published: May 2021

Abstract
A perturbative method of computing the total travel time of both null and lightlike rays in arbitrary static spherically symmetric spacetimes in the weak field limit is proposed. The resultant total time takes a quasi-series form of the impact parameter. The coefficient of this series at a certain order n is shown to be determined by the asymptotic expansion of the metric functions to the order

. For the leading order(s), the time delay, as well as the difference between the time delays of two types of relativistic signals, is shown to take a universal form for all SSS spacetimes. This universal form depends on the mass M and a post-Newtonian parameter

of the spacetime. The analytical result is numerically verified using the central black hole of galaxy M87 as the gravitational lensing center.
Impact of lepton p

T
threshold on charge asymmetry predictions for inclusive W boson production in pp collisions at 13 TeV
Authors: Ocalan Kadir 
Published: May 2021

Abstract
This paper presents the impact of the lepton transverse momentum

threshold on the

boson charge asymmetry predictions in perturbative QCD for the inclusive

production in proton-proton (

) collisions. The predictions are obtained at various low-

thresholds

20, 25, 30, and 40 GeV in a fiducial region encompassing both the central and forward detector acceptances in terms of the lepton pseudorapidity

. The predicted distributions for the lepton charge asymmetry, which is defined by

(

), at the next-to-next-to-leading order (NNLO) accuracy are compared with the CMS and LHCb data at 8 TeV center-of-mass collision energy. The 8 TeV predictions reproduce the data fairly well within the quoted uncertainties. The predictions from the CT14 parton distribution function (PDF) model are in a slightly better agreement with the data over the other PDF sets that are tested. The 13 TeV predictions using various

thresholds are reported for

and the charge asymmetries that are defined in terms of the differential cross sections in bins of the

boson rapidity

(

) and transverse momentum

(

). The NNLO predictions for the

,

, and

distributions are assessed to be in close correlation with the

value. The

and

distributions are particularly shown to be more correlated at a higher

threshold. The

distributions are also reported from the merged predictions with improved accuracy by the inclusion of the next-to-next-to-next-to-leading logarithm (N3LL) corrections, i.e., at NNLO+N3LL. The predicted distributions from various

thresholds represent a finer probe in terms of the capability to provide more constraints on the ratio of

and

quark distribution functions in the parton momentum fraction range

.
Costs of avoiding net negative emissions under a carbon budget
Authors: van der Wijst Kaj-Ivar , Hof Andries F , van Vuuren Detlef P 
Published: May 2021

Abstract
The 2 °C and 1.5 °C temperature targets of the Paris Agreement can be interpreted as targets never to be exceeded, or as end-of-century targets. Recent literature proposes to move away from the latter, in favour of avoiding a temperature overshoot and the associated net negative emissions. To inform this discussion, we investigate under which conditions avoiding an overshoot is economically attractive. We show that some form of overshoot is attractive under a wide range of assumptions, even when considering the extra damages due to additional climate change in the optimisation process. For medium assumptions regarding mitigation costs and climate damages, avoiding net negative emissions leads to an increase in total costs until 2100 of 5% to 14%. However, avoiding overshoot only leads to some additional costs when mitigation costs are low, damages are high and when using a low discount rate. Finally, if damages are not fully reversible, avoiding net negative emissions can even become attractive. Under these conditions, avoiding overshoot may be justified, especially when non-monetary risks are considered.
Contrasting the role of human- and lightning-caused wildfires on future fire regimes on a Central Oregon landscape
Authors: Barros Ana M G , Day Michelle A , Preisler Haiganoush K , Abatzoglou John T , Krawchuk Meg A , Houtman Rachel , Ager Alan A 
Published: May 2021

Abstract
Climate change is expected to increase fire activity in many regions of the globe, but the relative role of human vs. lightning-caused ignitions on future fire regimes is unclear. We developed statistical models that account for the spatiotemporal ignition patterns by cause in the eastern slopes of the Cascades in Oregon, USA. Projected changes in energy release component from a suite of climate models were used with our model to quantify changes in frequency and extent of human and lightning-caused fires and record-breaking events based on sizes of individual fires between contemporary (2006 −2015) and mid-century conditions (2031–2060). No significant change was projected for the number of human-caused fire ignitions, but we projected a 14% reduction in lightning-caused ignitions under future conditions. Mean fire sizes were 31% and 22% larger under future conditions (2031–2060) for human and lightning-caused ignitions, respectively. All but one climate model projected increased frequency of record-breaking events relative to the contemporary period, with the largest future fires being about twice the size of those of the contemporary period. This work contributes to understanding the role of lightning- and human-caused fires on future fire regimes and can help inform successful adaptation strategies in this landscape.
Long-term trends of satellite-based fine-mode aerosol optical depth over the Seto Inland Sea, Japan, over two decades (2001–2020)
Authors: Itahashi Syuichi , Sakurai Tatsuya , Shimadera Hikari , Araki Shin , Hayami Hiroshi 
Published: May 2021

Abstract
Air pollution over the Seto Inland Sea (SIS) is among the most severe of any region in Japan and is considered to be affected by both long-range and local pollution. To unravel the long-term trends of aerosol pollution over this region, in this study, measurements from the moderate resolution imaging spectroradiometer instrument onboard the Terra satellite were analyzed over two decades, from 2001 to 2020. Fine-mode aerosol optical depth (AODf) was calculated to estimate the amount of aerosol produced by anthropogenic emissions. The results showed that the AODf over the SIS increased from 2001 to 2004, had a flat trend from 2005 to 2009, and decreased from 2010 to 2020. To clarify the impact of long-range transport from the Asian continent to the SIS, the AODf over the Yellow Sea was also investigated and was found to increase and level off during the 2000s, after which it decreased, especially after 2014. This decrease can be attributed to emission regulations in China. The above analysis suggests that the aerosol pollution status in the SIS during the late 2010s was similar to that during the early 2000s. Over the SIS, the lowest AODf value was found in 2020, with the values in January–March and June–July approximately 30% and 30%–60% lower than the average values during the same periods in 2018–2019, respectively. The reduction found in January–March could be related to the decline in the long-range transport with restrictions on human activity due to the COVID-19 pandemic. Meanwhile, the reduction during June–July could be related to the decline of local emission sources. Considering the large SO2 decline in 2020, regulations on SO2 emitted from ships that started from 1 January 2020 are one possible factor for the improvement of aerosol pollution over the SIS in 2020.
Mapping the maximum extents of urban green spaces in 1039 cities using dense satellite images
Authors: Huang Conghong , Yang Jun , Clinton Nicholas , Yu Le , Huang Huabing , Dronova Iryna , Jin Jing 
Published: May 2021

Abstract
Spatial data of urban green spaces (UGS) are critical for cities worldwide to evaluate their progress towards achieving the urban sustainable development goals on UGS. However, UGS maps at the global scale with acceptable accuracies are not readily available. In this study, we mapped UGS of all 1039 mid- and large-sized cities across the globe in 2015 with dense remote sensing data (i.e. 51 494 Landsat images) and Google Earth Engine (GEE) platform. Also, we quantified the spatial distribution and accessibility of UGS within the cities. By combining the greenest pixel compositing method and the percentile-based image compositing method, we were able to obtain the maximum extent of UGS in cities while better differentiating UGS from other vegetation such as croplands. The mean overall classification accuracy reached 89.26% (SD = 3.26%), which was higher than existing global land cover products. Our maps showed that the mean UGS coverage in 1039 cities was 38.46% (SD = 20.27%), while the mean UGS accessibility was 82.67% (SD = 22.89%). However, there was a distinctive spatial equity issue as cities in high-income countries had higher coverage and better accessibility than cities in low-income countries. Besides developing a protocol for large-scale UGS mapping, our study results provide key baseline information to support international endeavors to fulfill the relevant urban sustainable development goals.
Effectiveness and impact studies of mangrove rehabilitation in the northern coast of West Java: A case study in Karawang Regency
Authors: Amin M A Al , Mulyana D , Damar A , Budiman M A K , Kamsari  
Published: May 2021

Abstract
Plenty of mangrove rehabilitation programs have been implemented on the northern coast of Java, including in Karawang Regency, both by the community and private companies’ participation through Corporate Social Responsibility (CSR). Over ten years, millions of mangrove plants have been planted. However, the results and impacts on the ecology and socio-economy have not been widely evaluated. An assessment and evaluation of the mangrove rehabilitation were carried out to determine the mangrove rehabilitation program’s results and effectiveness. This paper aims to determine rehabilitation’s condition and its impact on ecology and socio-economic surrounding the rehabilitation area. Mangrove rehabilitation activities at the northern coast of Karawang Regency have been provided new evidence that planting mangroves for rehabilitation purposes can not be seen as tree planting activities only. However, the impact and multiplier effects of its extraordinary benefits have not been paid much attention. Rehabilitation results have provided significant results, seen from the increase in the mangrove area, ecosystem quality, and positive impacts on ecology and significant socio-economic impacts indirect impacts, secondary impacts or cumulative impacts. It is necessary to develop and utilize rehabilitation results through a good socio-economic and institutional development approach to impact the community positively.