bluuebunny/crossref_metadata_2025 huggingface dataset:
Observation and quantification of inertial effects on the drift of floating objects at the ocean surface
Authors: Olascoaga M. J. , Beron-Vera F. J. , Miron P. , Triñanes J. , Putman N. F. , Lumpkin R. , Goni G. J.
Published: February 2020

We present results from an experiment designed to better understand the mechanism by which ocean currents and winds control flotsam drift. The experiment consisted of deploying in the Florida Current and subsequent satellite tracking of specially designed drifting buoys of various sizes, buoyancies, and shapes. We explain the differences in the trajectories described by the special drifters as a result of their inertia, primarily buoyancy, which constrains the ability of the drifters to adapt their velocities to instantaneous changes in the ocean current and wind that define the carrying flow field. Our explanation of the observed behavior follows from the application of a recently proposed Maxey–Riley theory for the motion of finite-sized particles floating on the ocean surface. The nature of the carrying flow and the domain of validity of the theory are clarified, and a closure proposal is made to fully determine its parameters in terms of the carrying fluid system properties and inertial particle characteristics.
Few-monolayer yttria-doped zirconia films: Segregation and phase stabilization
Authors: Lackner Peter , Brandt Amy J. , Diebold Ulrike , Schmid Michael
Published: February 2020

For most applications, zirconia (ZrO2) is doped with yttria. Doping leads to the stabilization of the tetragonal or cubic phase and increased oxygen ion conductivity. Most previous surface studies of yttria-doped zirconia were plagued by impurities, however. We have studied doping of pure, 5-monolayer ZrO2 films on Rh(111) by x-ray photoelectron spectroscopy (XPS), scanning tunneling microscopy (STM), and low-energy electron diffraction (LEED). STM and LEED show that the tetragonal phase is stabilized by unexpectedly low dopant concentrations, 0.5 mol % Y2O3, even when the films are essentially fully oxidized (as evidenced by XPS core level shifts). XPS also shows Y segregation to the surface with an estimated segregation enthalpy of −23 ± 4 kJ/mol.
Enhanced nanoscopy of individual CsPbBr3 perovskite nanocrystals using dielectric sub-micrometric antennas
Authors: Suárez Isaac , Wood Thomas , Pastor Juan P. Martinez , Balestri Dario , Checcucci Simona , David Thomas , Favre Luc , Claude Jean-Benoît , Grosso David , Gualdrón-Reyes Andrés F. , Mora-Seró Iván , Abbarchi Marco , Gurioli Massimo
Published: February 2020

We demonstrate an efficient, simple, and low-cost approach for enhanced nanoscopy in individual green emitting perovskite (CsPbBr3) nanocrystals via TiO2 dielectric nanoantenna. The observed three- to five-fold emission enhancement is attributed to near-field effects and emission steering promoted by the coupling between the perovskite nanocrystals and the dielectric sub-micrometric antennas. The dark-field scattering configuration is then exploited for surface-enhanced absorption measurements, showing a large increase in detection sensitivity, leading to the detection of individual nanocrystals. Due to the broadband spectral response of the Mie sub-micrometric antennas, the method can be easily extended to electronic transitions in other spectral regions, paving the way for absorption nanoscopy of many different quantum emitters from organic molecules to quantum dots.
First principles calculations of optoelectronic and magnetic properties of Co-doped and (Co, Al) co-doped ZnO
Authors: Khan Muhammad Sheraz , Shi Li-jie , Zou Bingsuo
Published: February 2020

Based on first principles calculations within spin polarized-density functional theory, we investigate optoelectronic and magnetic properties of Co-doped and (Co, Al) co-doped ZnO. Our results demonstrate that Co substitution changes the nonspin polarized state of pure ZnO to spin polarized with total magnetic moment of 3 μB. The origin of antiferromagnetic (AFM) coupling between Co spins in the ZnO lattice is guided mainly by a super-exchange mechanism without any additional defects. The effect of Al codoping on the ground state of Co-doped ZnO is also investigated, and we find that the additional electron introduced by Al codoping changes the magnetic ground state of Co-doped ZnO from AFM to FM state, and the estimated Curie temperature is expected to be higher than room temperature. The optical absorption spectra of pure ZnO and Co-doped systems for all compositions are investigated, and we find that with an increase in Co concentration, the bandgap of ZnO and the position of spin-allowed d–d transition peaks of Co spins exhibit a blueshift and redshift behavior, respectively, which are consistent with the experimental results. Al codoping produces absorption peaks near infrared light and visible-light regions and increases transition energy due to the Burstein–Moss effect. Furthermore, the bandgap and d–d transition peaks of Co spins are correlated with magnetic coupling, and we observed a redshift of fundamental bandgap and d–d transition peaks of Co ions for FM coupled Co spins, and blueshift for AFM coupled Co spin systems.
Anisotropic strain relaxation through prismatic and basal slip in α-(Al, Ga)2O3 on R-plane Al2O3
Authors: Grundmann M. , Lorenz M.
Published: February 2020

Pseudomorphic and partially relaxed layers of corundum phase (Al, Ga)2O3 epilayers on (01.2)-oriented Al2O3 fabricated by pulsed laser deposition (PLD) are investigated. An exact analytical (continuum elasticity) strain theory for rhombohedral heterostructures as a function of the two substrate orientation angles fits the strain state of pseudomorphic and relaxed samples very well. From reciprocal space maps and a quantitative analysis of x-ray diffraction peaks and tilts using the strain theory, it is concluded that in the present samples grown below 800 °C, plastic strain relaxation above the critical thickness occurs first through slip on the prismatic a-plane glide system and subsequently via the basal c-plane system. We also present a general PLD stoichiometry transfer model simultaneously explaining the epilayer alloy composition and growth rate in the entire composition range.
Venomic Interrogation Reveals the Complexity of Conus striolatus Venom
Authors: Himaya S. W. A. , Rai Subash K. , Pamfili Giulia , Jin Ai-Hua , Alewood Paul F. , Lewis Richard J.
Published: February 2020

Given the complexity of cone snail venoms, high throughput venomics approaches are required to fully investigate venom composition, envenomation strategies, and evolutionary trajectories. This study describes 158 conotoxins in the venom transcriptome of the little studied C. striolatus from the fish hunting clade Pionoconus. Despite similar gene superfamily distributions along the venom duct, only 18 common transcripts were identified between distal, central, and proximal venom duct transcriptomes. Proteomic analysis of the injected predatory venom collected from the same individual revealed an ~18-fold enhanced complexity at the proteomic level, consistent with complex post-translational modifications and variable venom peptide processing occurring in the venom duct. Overall, C. striolatus venom was dominated by M, O1, O2, and A gene superfamily conotoxins and conkunitzins, which are potential modulators of sodium, calcium, and potassium channels. Conkunitzins and gene superfamily A peptides dominated the proximal over the distal duct, the M and O1 gene superfamily peptides were distributed along the full length of the duct, while the O2 gene superfamily peptides dominated the distal duct. Interestingly, the predatory injected venom of C. striolatus was dominated by peptides from gene superfamilies M, O1, O2, A, and conkunitzins, suggesting the predatory venom of C. striolatus may arise at multiple sites along the venom duct.
Shark-catch composition and seasonality in the data-poor small-scale fisheries of the southern Gulf of Mexico
Authors: Pérez-Jiménez Juan Carlos , Wakida-Kusunoki Armando , Hernández-Lazo Chrystian , Mendoza-Carranza Manuel
Published: February 2020

Regional ecological information is relevant to the international management of vulnerable species such as sharks. On the basis of monthly fishery data (2007–2010) from two small-scale multispecies fleets, namely, the bottom longline fleet (MLL) and vertical line+shark-specific longline fleet (VL+SSL) operating on the Campeche Bank, we recorded 19 shark species. The occurrence of immature stages of 15 species, gravid females of Carcharhinus leucas, three Endangered species (Sphyrna mokarran, S. lewini, Isurus oxyrinchus) and three Vulnerable and six Near-threatened species emphasises the importance of this area. Rhizoprionodon terraenovae (42.01% of total abundance), S. lewini (24.82%) and S. tiburo (14.57%) were the most abundant species. The commercial logbooks (2007–2012) for one fleet recorded 6517 for MLL and 1617 for VL+SSL fishery trips. The general additive model indicated a maximum of shark catch rate (CR) for MLL and SSL during 2011 (mean±s.e., 49.94±8.44 and 91.38±16.07kg per 100 hooks respectively). Monthly CR for MLL was highly variable; the maximum was observed in February (15.45±21.43kg per 100 hooks), the maximum monthly CR for SSL was in January (88.04±14.85kg per 100 hooks). For MLL, a positive relation was observed between effort and CR, whereas, for SSL, no clear relation was observed.
Macropods, feral goats, sheep and cattle. 2. Equivalency in what and where they eat
Authors: Pahl Lester
Published: February 2020

The extent to which sheep, cattle, feral goats, red kangaroos, western grey kangaroos, euros and eastern grey kangaroos are equivalent in their use of the Australian southern rangelands is partly dependent on the extent to which their diets and foraging areas overlap. These herbivores all eat large amounts of green annual grasses, ephemeral forbs and the green leaf of perennial grasses when they are available. Overlap in use of these forages by all seven herbivores is concurrent and high. As the abundance of these preferred forages declines, sheep, cattle and feral goats consume increasing amounts of mature perennial grasses and chenopod and non-chenopod perennial forbs. Red kangaroos and western grey kangaroos continue to graze mature perennial grasses longer than sheep, cattle and feral goats, and only switch to perennial forbs when the quantity and quality of perennial grasses are poor. Consequently, overlap in use of perennial forbs by sheep, cattle, feral goats, red kangaroos and western grey kangaroos is sequential and moderately high. When palatable perennial forbs are eaten out, the diets of all herbivores except feral goats comprise predominantly dry perennial grass, and overlap is again concurrent and high. In comparison, feral goats have higher preferences for the browse of a wide range of shrubs and trees, and switch to these much earlier than the other herbivores. When perennial grasses and perennial forbs become scarce, sheep, feral goats and cattle browse large shrubs and trees, and overlap is sequential and high. If climatic conditions remain dry, then red and western grey kangaroos will also browse large shrubs and trees, but overlap between them, sheep, cattle and goats is sequential and low. In contrast to the other herbivores, the diets of euros and eastern grey kangaroos are comprised predominantly of perennial grasses, regardless of climatic conditions. As for diet composition, concurrent overlap in foraging distributions of sheep, cattle, feral goats and the four species of macropods is often low. However, over periods of several months to two or three years, as climatic conditions change, overlap in foraging distributions is sequential and high. While equivalency in what and where these herbivores eat is not quantifiable, it appears to be high overall. This is particularly so for perennial grass, which is the dominant forage for herbivores in the southern rangelands.
Do concerns about kangaroo management represent an existential threat for the red meat industry in the southern Australian rangelands?
Authors: Sinclair K. , Curtis A. L. , Atkinson T.
Published: February 2020

Concerns raised, including those voiced by animal rights and vegan activists, have limited the available practices by landholders in the southern Australian rangelands to effectively control kangaroos and, over time, the actions of these groups may threaten the existence of the livestock industry. This paper draws on interviews with key stakeholders and workshops with technical experts and red meat industry participants to identify strategies to respond to this potentially existential threat. Strategies include establishing platforms and processes for effective stakeholder engagement, establishing a unified and resourced industry ‘voice’ to effectively engage with government and other stakeholders, and ensuring that the industry self-regulates in order to avoid the potential for rogue elements to undermine its credibility and trustworthiness.
Maternal cumulative prevalence measures of child mortality show heavy burden in sub-Saharan Africa
Authors: Smith-Greenaway Emily , Trinitapoli Jenny
Published: February 2020

We advance a set of population-level indicators that quantify the prevalence of mothers who have ever experienced an infant, under 5-y-old child, or any-age child die. The maternal cumulative prevalence of infant mortality (mIM), the maternal cumulative prevalence of under 5 mortality (mU5M), and the maternal cumulative prevalence of offspring mortality (mOM) bring theoretical and practical value to a variety of disciplines. Here we introduce maternal cumulative prevalence measures of mortality for multiple age groups of mothers in 20 sub-Saharan African countries with Demographic and Health Surveys data spanning more than two decades. The exercise demonstrates the persistently high prevalence of African mothers who have ever experienced a child die. In some African countries, more than one-half of 45- to 49-y-old mothers have experienced the death of a child under age 5, and nearly two-thirds have experienced the death of any child, irrespective of age. Fewer young mothers have experienced a child die, yet in many countries, up to one-third have. Our results show that the mIM and mU5M can follow distinct trajectories from the infant mortality rate (IMR) and under 5 mortality rate (U5MR), offering an experiential view of mortality decline that annualized measures conceal. These measures can be adapted to quantify the prevalence of recurrent offspring mortality (mROM) and calculated for subgroups to identify within-country inequality in the mortality burden. These indicators can be used to improve current understandings of mortality change, bereavement as a public health threat, and population dynamics.
A hemipteran insect reveals new genetic mechanisms and evolutionary insights into tracheal system development
Authors: Hanna Lisa , Popadić Aleksandar
Published: February 2020

The diversity in the organization of the tracheal system is one of the drivers of insect evolutionary success; however, the genetic mechanisms responsible are yet to be elucidated. Here, we highlight the advantages of utilizing hemimetabolous insects, such as the milkweed bugOncopeltus fasciatus, in which the final adult tracheal patterning can be directly inferred by examining its blueprint in embryos. By reporting the expression patterns, functions, and Hox gene regulation oftrachealess (trh),ventral veinless(vvl), andcut(ct), key genes involved in tracheal development, this study provides important insights. First, Hox genes function as activators, modifiers, and suppressors oftrhexpression, which in turn results in a difference between the thoracic and abdominal tracheal organization. Second, spiracle morphogenesis requires the input of bothtrhandct, wherectis positively regulated bytrh. As Hox genes regulatetrh, we can now mechanistically explain the previous observations of their effects on spiracle formation. Third, the default state ofvvlexpression in the thorax, in the absence of Hox gene expression, features three lateral cell clusters connected to ducts. Fourth, the exocrine scent glands expressvvland are regulated by Hox genes. These results extend previous findings [Sánchez-Higueras et al., 2014], suggesting that the exocrine glands, similar to the endocrine, develop from the same primordia that give rise to the trachea. The presence of such versatile primordia in the miracrustacean ancestor could account for the similar gene networks found in the glandular and respiratory organs of both insects and crustaceans.
Early atmospheric contamination on the top of the Himalayas since the onset of the European Industrial Revolution
Authors: Gabrielli Paolo , Wegner Anna , Sierra-Hernández M. Roxana , Beaudon Emilie , Davis Mary , Barker Joel D. , Thompson Lonnie G.
Published: February 2020

Because few ice core records from the Himalayas exist, understanding of the onset and timing of the human impact on the atmosphere of the “roof of the world” remains poorly constrained. We report a continuous 500-y trace metal ice core record from the Dasuopu glacier (7,200 m, central Himalayas), the highest drilling site on Earth. We show that an early contamination from toxic trace metals, particularly Cd, Cr, Mo, Ni, Sb, and Zn, emerged at high elevation in the Himalayas at the onset of the European Industrial Revolution (∼1780 AD). This was amplified by the intensification of the snow accumulation (+50% at Dasuopu) likely linked to the meridional displacement of the winter westerlies from 1810 until 1880 AD. During this period, the flux and crustal enrichment factors of the toxic trace metals were augmented by factors of 2 to 4 and 2 to 6, respectively. We suggest this contamination was the consequence of the long-range transport and wet deposition of fly ash from the combustion of coal (likely from Western Europe where it was almost entirely produced and used during the 19th century) with a possible contribution from the synchronous increase in biomass burning emissions from deforestation in the Northern Hemisphere. The snow accumulation decreased and dry winters were reestablished in Dasuopu after 1880 AD when lower than expected toxic metal levels were recorded. This indicates that contamination on the top of the Himalayas depended primarily on multidecadal changes in atmospheric circulation and secondarily on variations in emission sources during the last 200 y.
Orbital pacing and secular evolution of the Early Jurassic carbon cycle
Authors: Storm Marisa S. , Hesselbo Stephen P. , Jenkyns Hugh C. , Ruhl Micha , Ullmann Clemens V. , Xu Weimu , Leng Melanie J. , Riding James B. , Gorbanenko Olga
Published: February 2020

Significance

Cyclic variations in Earth’s orbit drive periodic changes in the ocean–atmosphere system at a time scale of tens to hundreds of thousands of years. The Mochras δ
13
C
TOC
record illustrates the continued impact of long-eccentricity (405-ky) orbital forcing on the carbon cycle over at least ∼18 My of Early Jurassic time and emphasizes orbital forcing as a driving mechanism behind medium-amplitude δ
13
C fluctuations superimposed on larger-scale trends that are driven by other variables such as tectonically determined paleogeography and eruption of large igneous provinces. The dataset provides a framework for distinguishing between internal Earth processes and solar-system dynamics as the driving mechanism for Early Jurassic δ
13
C fluctuations and provides an astronomical time scale for the Sinemurian Stage.
Centrioles control the capacity, but not the specificity, of cytotoxic T cell killing
Authors: Tamzalit Fella , Tran Diana , Jin Weiyang , Boyko Vitaly , Bazzi Hisham , Kepecs Ariella , Kam Lance C. , Anderson Kathryn V. , Huse Morgan
Published: February 2020

Significance

CTLs fight intracellular pathogens and cancer by forming a close cell–cell interaction, called the immunological synapse with an infected or transformed target cell and then releasing toxic proteins directionally into the synaptic space. Directional secretion is thought to depend on the polarization of the CTL centrosome to a position just beneath the center of the synapse. We show here that CTLs lacking centrioles, which are the core structural components of centrosomes, unexpectedly retain the capacity for polarized secretion. Nevertheless, they kill target cells poorly because they fail to package toxic proteins effectively and form properly organized synapses. This paper establishes novel links among the centrosome, organelle maturation, and the dynamic architecture of cell–cell interfaces.
Role for ribosome-associated quality control in sampling proteins for MHC class I-mediated antigen presentation
Authors: Trentini Débora Broch , Pecoraro Matteo , Tiwary Shivani , Cox Jürgen , Mann Matthias , Hipp Mark S. , Hartl F. Ulrich
Published: February 2020

Mammalian cells present a fingerprint of their proteome to the adaptive immune system through the display of endogenous peptides on MHC-I complexes. MHC-I−bound peptides originate from protein degradation by the proteasome, suggesting that stably folded, long-lived proteins could evade monitoring. Here, we investigate the role in antigen presentation of the ribosome-associated quality control (RQC) pathway for the degradation of nascent polypeptides that are encoded by defective messenger RNAs and undergo stalling at the ribosome during translation. We find that degradation of model proteins by RQC results in efficient MHC-I presentation, independent of their intrinsic folding properties. Quantitative profiling of MHC-I peptides in wild-type and RQC-deficient cells by mass spectrometry showed that RQC substantially contributes to the composition of the immunopeptidome. Our results also identify endogenous substrates of the RQC pathway in human cells and provide insight into common principles causing ribosome stalling under physiological conditions.
The typhoon-induced drying of the Maritime Continent
Authors: Scoccimarro Enrico , Gualdi Silvio , Bellucci Alessio , Peano Daniele , Cherchi Annalisa , Vecchi Gabriel A. , Navarra Antonio
Published: February 2020

Significance

Much work has been done to quantify tropical cyclone (TC)-induced precipitation and its role in determining flood events. We identify the role of tropical cyclones in reducing precipitation over particular areas of the tropical domain. The significant reduction in the precipitation over the Maritime Continent when the TC season is particularly active is in line with the net reduction in westward water flow into the Maritime Continent atmosphere, induced by TC-associated circulation over the region.
Mesoscale structure of wrinkle patterns and defect-proliferated liquid crystalline phases
Authors: Tovkach Oleh , Chen Junbo , Ripp Monica M. , Zhang Teng , Paulsen Joseph D. , Davidovitch Benny
Published: February 2020

Significance

Thin films readily buckle to relax compression, creating wrinkle patterns that may cover large portions of the solid. Predicting the arrangement of wrinkles in general settings is a major challenge that affects our understanding of stresses and deformations in textiles, biological tissues, and synthetic skins. We identify a mesoscale structure that arises from the incompatibility of uniformly spaced wrinkles and a spatially varying director, unraveling an organizing principle with analogs in liquid crystalline and superconducting states of matter.
Evaluating two ways for marking Swedish phonological length in written text
Authors: Thorén Bosse , Jeong Hyeseung
Published: February 2020

The study compares two different graphic marking systems designed to help L2 learners of Swedish notice and
realize phonological length. In System A, 22 L2 learners read aloud three /VːC/ words with length marked under long vowels and
three /VCː/words with dots under short vowels. Twenty-two other L2 learners read the same words marked by the other system (System
B) that underlines long vowels and long consonants. As a control group, 20 native Swedish speakers read the same words without any
marking. We measured and compared the temporal realizations of the six words by all the three groups. System B readers realized
Swedish phonological length more closely to the way that native speakers did, compared to System A readers. These results suggest
that prompting both long vowels and long consonants can be more effective than marking long and short vowels.
Iconicity in syntax and the architecture of linguistic theory
Authors: Krivochen Diego Gabriel , Lacková Ľudmila
Published: February 2020

Linguistic iconicity has been studied since ancient times (e.g., Plato’s Cratylus, see Cooper & Hutchinson 1997). Within modern grammatical description, this notion was
mostly developed by Jakobson and Benveniste; nowadays, iconicity in language is even being experimentally tested (e.g., Blasi et al. 2016; Diatka & Milička 2017).
However, most studies on linguistic iconicity pertain to prosody, sound symbolism, or morphology; syntactic iconicity has been
vastly underexplored. In this paper, we present two hypotheses concerning syntactic iconicity: (1) syntactic
descriptions of natural language strings have an inherent structure which is isomorphic to that of representations in some other
component of grammar or a non-grammatical system; or (2) linear order imposed on phrase structure is isomorphic to that in some
other component of grammar or a non-grammatical system. We will argue in favour of the former, which constitutes a novel
perspective on iconicity in grammar. We furthermore discuss the place that iconicity may have in the architecture of a generative
system.
Nominal classification
Authors: Feist Timothy
Published: February 2020

It is often claimed that reference tracking is a key function of nominal classification systems, not least because of the role such systems can play in referent disambiguation. This paper reports on the results of a comparative study of reference in texts from four languages, focusing specifically on the disambiguating function of nominal classification. The results strongly suggest that disambiguation is not a primary function of nominal classification systems. While gender and/or classifiers sometimes contribute to the avoidance of referential conflict, the reality is that the conditions have to be just right – all competing references must be of opposing genders, and those genders must be formally distinct – and this happens with surprisingly low frequency. We are better off viewing disambiguation as a convenient by-product of nominal classification systems that a language can exploit when conditions allow.
Recent progress in porous TiNb-based alloys for biomedical implant applications
Authors: Li Yong-Hua , Shang Xiao-Yang
Published: February 2020

Porous TiNb-based alloys have attracted considerable attention in the medical field of orthopedic applications because of excellent biocompatibility, porous architecture, appropriate mechanical property, etc. The literature reviews the current progress of fabrication methods, porous structure, mechanical properties, corrosion resistance, bioactive hydroxyapatite surface modification, in vitro and in vivo biocompatibility of porous TiNb-based alloy. Moreover, future research directions are pointed out to expand its possible biomedical applications.
Characterisation of a charged particle levitated nano-oscillator
Authors: Bullier N P , Pontin A , Barker P F
Published: February 2020

We describe the construction and characterisation of a nano-oscillator formed by a Paul trap. The frequency and temperature stability of the nano-oscillator was measured over several days allowing us to identify the major sources of trap and environmental fluctuations. We measure an overall frequency stability of 2 ppm h−1 and a temperature stability of more than 5 h via the Allan deviation. Importantly, we find that the charge on the nanoscillator is stable over a timescale of at least two weeks and that the mass of the oscillator, can be measured with a 3% uncertainty. This allows us to distinguish between the trapping of a single nanosphere and a nano-dumbbell formed by a cluster of two nanospheres.
Origin of magnetoresistance across the martensitic transformation: formation of phase fraction
Authors: Modak M , Ray Mayukh K , Mondal S , Maji B , Bagani K , Bhattacharyya A , Banerjee S
Published: February 2020

The influence of martensite and austenite phase volume fractions on the magnetoresistance have been studied across the first order martensite transformation of the Ni44Cu2Mn43In11 compound. The different phase volume fractions are calculated by measuring the resistivity as a function of temperature and magnetic field. Our experiment reveals that the field-induced austenite phase fraction (
f

IA

) at any temperature depends on the availability and instability of the martensite phase fraction (
f

M

) at that temperature. This
f

IA

is found to contribute most significantly to the observed large magnetoresistance (MR), while the contributions from parent martensite and austenite phase fractions are negligible. It has been found that the MR does not depend linearly on the
f

IA

. On application of a magnetic field, the ascending and descending branch of the
f

IA

follows a different power law, giving rise to hysteresis in the MR.
Revisiting the quantum field theory of neutrino oscillations in vacuum
Authors: Grimus W
Published: February 2020

We consider neutrino oscillations in vacuum in the framework of quantum field theory in which neutrino production and detection processes are part of a single Feynman diagram and the corresponding cross section is computed in the standard way, i.e. with final states represented by plane waves. We use assumptions which are realized in actual experiments and concentrate on the detection process. Moreover, we also allow for a finite time interval of length τ during which the detector records neutrino events. In this context we are motivated by accelerator-neutrino oscillation experiments where data taking is synchronized in time with the proton spill time of the accelerator. Given the final momenta and the direction of neutrino propagation, we find that in the oscillation amplitude—for all practical purposes—the neutrino energy Q is fixed, apart from an interval of order 2πℏ/τ around a mean energy

Q

¯

;

this is an expression of energy non-conservation or the time-energy uncertainty relation in the detection process due to

τ
<
∞

. We derive in excellent approximation that in the amplitude the oscillation effect originates from massive neutrinos with the same energy

Q

¯

, i.e. oscillations take place in space without any decoherece effect, while the remaining integration over Q in the interval of order 2πℏ/τ around

Q

¯

results in a time-correlation function expressing the time delay between neutrino production and detection.
Far-field sectioning for the retrieval of subwavelength grating parameters using coherent Fourier scatterometry
Authors: Siaudinyte Lauryna , Pereira Silvania F
Published: February 2020

Optical inspection of periodic nanostructures is a major challenge in the semiconductor industry due to constantly decreasing critical dimensions. In this paper we combine coherent Fourier scatterometry (CFS) with a sectioning mask for subwavelength grating parameter determination. By selecting only the most sensitive regions of the scattered light in the Fourier plane, one can retrieve grating parameters faster and with higher sensitivity than previous approaches. Moreover, the full process of CFS using focused light is explained and implemented in a subwavelength grating regime. The results of using transverse magnetic polarized input fields together with the proposed sectioning mask are presented and compared to the non-mask case.
Thermal expansion and compressibility of single-crystal silicon between 285 K and 320 K
Authors: Bartl Guido , Elster Clemens , Martin Jörg , Schödel René , Voigt Michael , Walkov Alexander
Published: February 2020

The absolute length of a single-crystal silicon gauge block was measured by interferometry in the temperature range between 285 K and 320 K and at different air pressures from atmospheric conditions down to 10−5 hPa. From the obtained dataset, the coefficient of thermal expansion (CTE) was determined as well as the compressibility—or the bulk modulus—of single-crystal silicon in consideration of a systematic correction of the refractometer used. As the choice of the underlying model for the evaluation is not unambiguous, a Bayesian model averaging approach was applied to take into account possible model errors in the uncertainty evaluation. The result of the CTE is not only in agreement with the recommended reference data of CODATA, but provides a standard uncertainty of less than 1 × 10−9 K−1, which is less than half the uncertainty stated so far in the relevant temperature range.
Microchemistry-dependent simulation of yield stress and flow stress in non-heat treatable Al sheet alloys
Authors: Wong Su Leen , Laptyeva Galyna , Brüggemann Thiemo , Engler Olaf , Roters Franz , Raabe Dierk , Karhausen Kai-Friedrich
Published: February 2020

A flow stress model which considers the processing conditions for a given alloy composition as well as the microchemistry of the alloy allows for integrated optimization of alloy composition, thermal treatments and forming operations to achieve the desired properties in the most efficient processing route. In the past, a statistical flow stress model for cell forming metals, 3IVM+ (3 Internal Variable Model), has been used for through process modeling of sheet production. However, this model was restricted to a given alloy in the state in which it was calibrated. In this work, the existing 3IVM+ model is augmented with an analytical solute strengthening model which uses input from ab initio simulations. Furthermore, a new particle strengthening model for non-shearable precipitates has been introduced which takes Orowan looping at low temperatures and dislocation climb at high temperatures into account. Hence, the present modeling approach considers the strengthening contributions from solutes, precipitates and forest dislocations. Three case studies on the alloys AA 1110, AA 3003 and AA 8014 are presented to assess the performance of the model in simulating the yield stress and flow stress of Al alloys over a wide range of temperatures and strain rates.
Systematic quantification of nanoscopic dose enhancement of gold nanoparticles in ion beams
Authors: Fuss M C , Boscolo D , Durante M , Scifoni E , Krämer M
Published: February 2020

High-Z material nanoparticles are being studied as localized dose enhancers in radiotherapeutic applications. Here, the nano-scale physical dose enhancement of proton, carbon and oxygen ion beam radiation by gold nanoparticles was studied by means of Monte Carlo track structure simulation with the TRAX code. We present 2D distributions and radial profiles of the additional dose and the dose enhancement factor for two geometries which consider an isolated and a water-embedded nanoparticle, respectively. Different nanoparticle sizes (radius of 1.2–22 nm) were found to yield qualitatively different absolute and relative dose enhancement distributions and different maximum dose enhancement factors (up to 20). Whereas the smallest nanoparticles produced the highest local dose enhancement factor close to the metal, larger ones led to lower, more diffuse dose enhancement factors that contributed more at larger distances. Differential absorption effects inside the metal were found to be responsible for those characteristics. For the energy range 15–204 MeVu−1, also a mild trend with ion E/A, regardless of the ion species, was found for embedded nanoparticles. In analogy to the width of the ion track itself, slower ions increased the enhancement at the nanoparticle surface. In contrast, no dependence on linear energy transfer was encountered. For slower ions (3–10 MeVu−1), the enhancement effect began to break down over all distances. Finally, the significance of any indirect physical effect was excluded, giving important hints especially in view of the low probabilities (at realistic concentrations and fluences) of direct ion-NP-hits. The very localized nature of the physical dose enhancement found suggests a strong action upon targets closeby, but no relevant effect at cellular distances. When pondering different possible damage enhancement mechanisms of gold nanoparticles in the context of published in vitro and in vivo experimental results, biological pathways are likely to play the key role.
Expanded capabilities of the CarMa code in modeling resistive wall mode dynamics with 3-D conductors
Authors: Bonotto M , Liu Y Q , Villone F , Pigatto L , Bettini P
Published: February 2020

In this work, an improved version of the CarMa code is presented, called CarMa-D, for the analysis of resistive wall modes (RWMs) in fusion devices, simultaneously considering the effects of volumetric three-dimensional conducting structures, plasma dynamics, toroidal rotation or drift-kinetic damping. Unlike static CarMa, CarMa-D does not rely on the simplifying assumptions such as neglecting the plasma mass, toroidal rotation and kinetic damping. The new coupling strategy is based on matrix-based Padé rational functions approximation of plasma a response. The arising mathematical model is formally equivalent to the original CarMa model, but with a higher number of degrees of freedom to model the dynamics of the plasma. CarMa-D overcomes the main limitations of the original CarMa, in particular: (i) the massless assumption for the plasma is removed, allowing modeling of global modes growing both on ideal kink time scales and in the typical RWM growth rate regime, with a suitable treatment of the model; (ii) the effects of toroidal plasma flow and drift kinetic damping can be included into the new model, providing a powerful tool to study macroscopic phenomena where both plasma dynamics and 3-D conducting structures play important roles.
Light-shift spectroscopy of optically trapped atomic ensembles
Authors: Hilton Ashby P , Luiten Andre N , Light Philip S
Published: February 2020

We develop a method for extracting the physical parameters of interest for a conventional dipole-trapped cold atomic ensemble. This technique uses the spatially dependent ac-Stark shift of the trap itself to project the atomic distribution onto a light-shift broadened transmission spectrum. We develop a model that connects the atomic distribution with the expected transmission spectrum. We then demonstrate the utility of the technique by deriving the temperature, trap depth, lifetime, and trapped atom number from data that was taken in a single shot experimental measurement.
Statistics of first-passage Brownian functionals
Authors: Majumdar Satya N , Meerson Baruch
Published: February 2020

We study the distribution of first-passage functionals of the type

where

represents a Brownian motion (with or without drift) with diffusion constant D, starting at x
0  >  0, and t

f 
is the first-passage time to the origin. In the driftless case, we compute exactly, for all n  >  −2, the probability density

. We show that

has an essential singular tail as

and a power-law tail

as

. The leading essential singular behavior for small A can be obtained using the optimal fluctuation method (OFM), which also predicts the optimal paths of the conditioned process in this limit. For the case with a drift toward the origin, where no exact solution is known for general n  >  −1, we show that the OFM successfully predicts the tails of the distribution. For

it predicts the same essential singular tail as in the driftless case. For

it predicts a stretched exponential tail

for all n  >  0. In the limit of large Péclet number

, where

is the drift velocity toward the origin, the OFM predicts an exact large-deviation scaling behavior, valid for all A:

, where

is the mean value of

in this limit. We compute the rate function

analytically for all n  >  −1. We show that, while for n  >  0 the rate function

is analytic for all z, it has a non-analytic behavior at z  =  1 for  −1  <  n  <  0 which can be interpreted as a dynamical phase transition. The order of this transition is 2 for  −1/2  <  n  <  0, while for  −1  <  n  <  −1/2 the order of transition is

; it changes continuously with n. We also provide an illuminating alternative derivation of the OFM result by using a WKB-type asymptotic perturbation theory for large

. Finally, we employ the OFM to study the case of

(drift away from the origin). We show that, when the process is conditioned on reaching the origin, the distribution of

coincides with the distribution of

for

with the same

.
Study on the utilization of palm fruit waste as a pulp raw material organosolv method with hydrothermal pretreatment
Authors: Apriani R , Manik N N , Mahardhika E H , Inayatullah M J
Published: February 2020

Palm fronds contain high cellulose, so it can be used as an alternative raw material for making pulp. The purpose of this study is to look at the potential of palm fronds as raw material for making pulp. The process of making pulp used in this study is the organosolv process, which is releasing palm frond fibers with a solution of acetic acid with hydrothermal pretreatment. This study observed the effect of cooking time and cooking solution volume on percent yield. The range of variables used in this study was cooking time of 125,150 and 175 minutes with concentrations of acetic acid cooking solution of 10 percent and 15 percent. The results of pulp quality were analyzed by comparing the results of the cold soda process to obtain physical properties. The best pulp was obtained at 30 minutes cooking time and 175 °C with a tensile value of 0.63 kN / m, tear 228.49 mN and brigthness 13.18.
Comparison study of lignin-kraft extraction process from black liquor using centrifuge and thermal acid hydrolysis methods
Authors: Susilo N A , Chaniago R D
Published: February 2020

Black liquor is a remnant of pulping fluid which generally consists of 14-18 percent solids which is commonly known as weak black liquor (WBL) with a pH of 12 or more. About 65 percent of the solids contained in black liquor are organic compounds derived from wood such as lignin, resins and fatty acids, acids from carbohydrates, and other organic compounds; The remaining 35percent percent is white liquor which is used in the pulping process. Kraft lignin, also called sulfate or alkali lignin, is obtained from black liquor by the extraction method using an acid hydrolysis process, so that pure kraft lignin compounds can be obtained which can be further utilized in various industrial activities. This study is comparing two kraft lignin extraction methods of acid hydrolysis process with thermal assistance (heating temperature) and a gradual centrifuge. The experiment results showed that the levels of lignin contained in black liquor consist of total calories of 391 kcal / Kg which can be processed into energy sources in the recovery boiler unit in further process. The result of kraft lignin extraction process using the acid hydrolysis method with gradual centrifuge stage is better than the thermal acid hydrolysis method. Quantitatively calculated with ASL values difference of around 0.002 mg / g of both the method and the AIR Value using centrifuge give an average yield of 969.815 mg / g, while using thermal assistance gives an average yield of 679.790 mg / g. Qualitatively, the centrifuge method is more optimal compared to the thermal method shown by the results of ICP, FTIR and SEM testing.
Using traffic signs in children’s shoes and metalworking design
Authors: Peng L H , Yu R R , Indarti
Published: February 2020

According to research, the current situation of declining of children’s birth rate is becoming a serious social issue in Taiwan. Therefore, most parents are willing to give their children the best care, and the trend of children’s goods is refined and more creative. It can be seen that modern people are not afraid of expensive but pay more attention to quality and creativity. This study takes the common traffic signs as design target. Modern children’s living environment is becoming more scientific and less exposed to outdoor activities. The preschool children’s vision is not broad enough to judge the meaning of the traffic sign. Therefore, in the news reports, people often see cases of children misunderstanding the road, leading to tragedy. Parents play an important role in the child’s growth and must teach children to identify relevant signs at the right time.This study hopes to teach children the correct concept of transportation through relevant designs. Although the elements of traffic signs are very simple, the more complex the environment, the more streamlined it is to achieve simplicity and order. The ultimate goal of this study is to make children curious about the goods and teach the correct concept of transportation.
Analysis of the quality of wheel chain products at UPT logam Yogyakarta using FMEA method
Authors: Yunitasari E W , Widiastuti R , Wisnuaji B S , Erwinda M , Sutanta E
Published: February 2020

Product quality measurement is an important aspect of the production process. This study aims to determine the types of defects that often occur and find a recommendation for improvement to CNC machine product of Takamaz GSL 15 at Technical Implementing Unit Metal Yogyakarta. In this study, a Pareto diagram is used for analysis the types of defects. Analysis of priority value regarding severity (S), occurrence (O), and detection (D) characteristics is performed by using Failure Mode and Effect Analysis (FMEA) method. Meanwhile, Fishbone is used to analyze more deeply about the potential caused by the type of defect. This study succeeded in finding four types of records on the product; they are cracked pinhole, imperfect castings, hole defects on the surface, and minus drain lines. This study recommend to include periodic and ongoing supervision of the metal casting process, make metal wheel chain in one production line, use modern equipment or machines, replace the drill bits periodically during machining process and replace sandpaper with a softness level according to SOP.
A study of learning motivation of senior high schools by applying unity and mblock on programming languages courses
Authors: Peng L H , Bai M-H , Siswanto I
Published: February 2020

This study aims to explore whether high school students can enhance students’ learning motivation through challenging learning situationsin programming courses. This study was conducted for 12th-grade students in high school. The experiment lasted for eight weeks. Measurements included Pre- and post-tests measure MSLQ (Motivated Strategies for Learning Questionnaire) and the performance of programming. The experimental group learning design the game interactive project in Unity with C# programming language, and the control group learning build Arduino interactive project in mBlock with block-based programming. The results showed that there was no significant difference in performance, but the learning motivation of the experimental group was lower than that of the control group.