bluuebunny/crossref_metadata_2025 huggingface dataset:
Visualizing curing process inside polymers
Authors: Dong Bo , Pan Bing
Published: February 2020

The curing process of polymer materials and structures has a crucial influence on their final properties. However, existing methods are only capable of characterizing their time-resolved information. To comprehensively reveal curing behaviors inside polymers, we report a method that combines optical coherence tomography and quantitative phase imaging for visualizing time- and space-resolved curing degree (or curing rate) distributions. For validation, the curing process of a polymer droplet was monitored by using the proposed method, which not only revealed that the curing rate of the polymer surface is faster than that of the interior but also discovered the depth-dependent gelation process. The experimental results indicate that the proposed method can effectively reveal curing behaviors inside polymers, which opens new possibilities for better understanding curing kinetics.
Evolution from random lasing to erbium-related electroluminescence from metal-insulator-semiconductor structured light-emitting device with erbium-doped ZnO film on silicon
Authors: Chen Jinxin , Wang Ziwei , Cao Jiahao , Yang Deren , Ma Xiangyang
Published: February 2020

A type of metal–insulator–semiconductor (MIS) structured light-emitting device (LED), where a semitransparent gold (Au) film, a polymethyl methacrylate film, and an erbium (Er)-doped ZnO (ZnO:Er) film on a silicon substrate act as the “M”, “I”, and “S” components, respectively, has been prepared. With increasing forward bias with the positive voltage connected to the semitransparent “M” (Au) electrode, such LED first exhibits random lasing (RL) from the ZnO host itself and is then electroluminescent with the characteristic emissions from the Er3+ ions incorporated into the ZnO host. Based on the energy band diagram and the analysis of carrier transportation for the ZnO:Er-based LED applied with different forward bias voltages, the evolution from the RL to the Er-related electroluminescence as mentioned above has been tentatively explained.
The striking influence of oxophilicity differences in heterometallic Mo–Mn oxide cluster reactions with water
Authors: Mason Jarrett L. , Gupta Ankur K. , McMahon Abbey J. , Folluo Carley N. , Raghavachari Krishnan , Jarrold Caroline Chick
Published: February 2020

Mixed-metal oxides have proven to be effective catalysts for the hydrogen evolution reaction, often outperforming either of the binary metal oxides. The reactivity of MnxMoOy− (x = 1, 2; y = 3, 4) clusters toward H2O was investigated via time-of-flight mass spectrometry with clear evidence of cluster oxidation and corresponding H2 production, specifically for MnxMoO3− (x = 1, 2) clusters. Unlike previously studied MoxOy− clusters, which assumed a broad distribution of stoichiometries (typically x ≤ y ≤ 3x), both MnMoOy− and Mn2MoOy− preferentially formed y = 3 and 4 compositions in significant quantities under our source conditions. The electronic and molecular structures of the MnxMoOy (x = 1, 2; y = 3, 4) anion and neutral clusters were probed with anion photoelectron spectroscopy and analyzed with supporting density functional theory calculations. Our studies suggest that both metal centers are involved in initial cluster–water complex formation, while Mo is the center that undergoes oxidation; hence, reactivity terminates when Mo is saturated in its highest oxidation state of +6. Across these four clusters, Mn remains relatively reduced and is stable in a high-spin electronic configuration. The preferential reactivity of water molecules toward the Mo center rather than Mn is rationalized by the much lower relative oxophilicity of Mn.
Probing Intramolecular Interaction of Stereoisomers Using Computational Spectroscopy
Authors: Wang Feng , Islam Shawkat , Backler Frederick
Published: February 2020

Several model stereoisomers such as ferrocene (Fc), methoxyphenol, and furfural conformers are discussed. It was discovered that the Fc IR spectroscopic band(s) below 500cm−1 serve as fingerprints for eclipsed (splitting 17 (471–488)cm−1) and staggered Fc (splitting is ~2 (459–461)cm−1) in the gas phase. It is revealed that in the gas phase the dominance of the eclipsed Fc (D5h) at very low temperatures changes to a mixture of both eclipsed and staggered Fc when the temperature increases. However, in solvents such as CCl4, eclipsed Fc dominates at room temperature (300K) due to the additional solvation energy. Intramolecular interactions of organic model compounds such as methoxyphenols (guaiacol (GUA) and mequinol (MEQ)) and furfural, ionization energies such as the carbon 1s (core C1s), as well as valence binding energy spectra serve this purpose well. Hydrogen bonding alters the C1s binding energies of the methoxy carbon (C(7)) of anti-syn and anti-gauche conformers of GUA to 292.65 and 291.91eV, respectively. The trans and cis MEQ conformers, on the other hand, are nearly energy degenerate, whereas their dipole moments are significantly different: 2.66 Debye for cis and 0.63 Debye for trans-MEQ. Moreover, it is found that rotation around the Cring–OH and the Cring–OCH3 bonds differ in energy barrier height by ~0.50 kcal⋅mol−1. The Dyson orbital momentum profiles of the most different ionic states, 25a′ (0.35eV) and 3a′ (−0.33eV), between cis and trans-MEQ in outer valence space (which is measurable using electron momentum spectroscopy (EMS)), exhibit quantitative differences. Finally, the molecular switch from trans and cis-furfural engages with a small energy difference of 0.74 kcal mol−1, however, at the calculated C(3)(–H⋅⋅⋅O=C) site the C1s binding energy difference is 0.105eV (2.42 kcal mol−1) and the NMR chemical shift of the same carbon site is also significant; 7.58ppm from cis-furfural without hydrogen bonding.
A quasi-experimental text messaging trial to improve adolescent sexual and reproductive health and smoking knowledge in Indonesia
Authors: Pedrana Alisa E. , Pina Jamie , Padmawati Retna S. , Zuhrina Ririh , Lazuardi Lutfan , Lim Megan S. C. , Hellard Margaret E. , Prabandari Yayi S.
Published: February 2020

Background To evaluate the feasibility and acceptability of a text message intervention to improve young people’s knowledge of sexual reproductive health (SRH) and harms related to smoking in Indonesia. Methods: A quasi-experimental short message service (SMS) trial of young people aged 16–24 years receiving twice weekly SMS over a 10-week intervention period. Pre- and post-online demographic and risk behaviour surveys were used to assess changes in knowledge. Among respondents who completed both surveys, we assessed changes in knowledge before and after SMS intervention using paired McNemar’s test and differences in mean knowledge score using a paired t-test. Results: In total, 555 eligible young people were enrolled into the SMS intervention; 235 (42%) completed a follow-up survey, of which 198 (84%) were matched to a baseline survey. Median age of participants was 19 years and the majority were female (63%). The mean knowledge score significantly increased between baseline and follow-up surveys for SRH questions [2.7, (95% CI 2.47, 2.94) vs 3.4 (95% CI 2.99, 3.81) (P = <0.01)] and smoking-related questions [3.8 (95% CI 3.66, 3.99) vs 4.1 (95% CI 3.99, 4.28) (P = 0.03)]. A majority of participants reported that the SMS intervention increased their knowledge (95%) and were a useful reminder (95%). Conclusions: An SMS intervention was feasible, acceptable and improved adolescents’ SRH knowledge and smoking knowledge in a low- to middle-income setting. SMS interventions targeting young people need to be scaled up, with the potential to explore additional topics around healthy lifestyle, nutrition and physical activity.
Activation of mosquito immunity blocks the development of transmission-stage filarial nematodes
Authors: Edgerton Elizabeth B. , McCrea Abigail R. , Berry Corbett T. , Kwok Jenny Y. , Thompson Letitia K. , Watson Brittany , Fuller Elizabeth M. , Nolan Thomas J. , Lok James B. , Povelones Michael
Published: February 2020

Mosquito-borne helminth infections are responsible for a significant worldwide disease burden in both humans and animals. Accordingly, development of novel strategies to reduce disease transmission by targeting these pathogens in the vector are of paramount importance. We found that a strain of
Aedes aegypti
that is refractory to infection by
Dirofilaria immitis
, the agent of canine heartworm disease, mounts a stronger immune response during infection than does a susceptible strain. Moreover, activation of the Toll immune signaling pathway in the susceptible strain arrests larval development of the parasite, thereby decreasing the number of transmission-stage larvae. Notably, this strategy also blocks transmission-stage
Brugia malayi
, an agent of human lymphatic filariasis. Our data show that mosquito immunity can play a pivotal role in restricting filarial nematode development and suggest that genetically engineering mosquitoes with enhanced immunity will help reduce pathogen transmission.
Individual-specific functional connectivity of the amygdala: A substrate for precision psychiatry
Authors: Sylvester Chad M. , Yu Qiongru , Srivastava A. Benjamin , Marek Scott , Zheng Annie , Alexopoulos Dimitrios , Smyser Christopher D. , Shimony Joshua S. , Ortega Mario , Dierker Donna L. , Patel Gaurav H. , Nelson Steven M. , Gilmore Adrian W. , McDermott Kathleen B. , Berg Jeffrey J. , Drysdale Andrew T. , Perino Michael T. , Snyder Abraham Z. , Raut Ryan V. , Laumann Timothy O. , Gordon Evan M. , Barch Deanna M. , Rogers Cynthia E. , Greene Deanna J. , Raichle Marcus E. , Dosenbach Nico U. F.
Published: February 2020

The amygdala is central to the pathophysiology of many psychiatric illnesses. An imprecise understanding of how the amygdala fits into the larger network organization of the human brain, however, limits our ability to create models of dysfunction in individual patients to guide personalized treatment. Therefore, we investigated the position of the amygdala and its functional subdivisions within the network organization of the brain in 10 highly sampled individuals (5 h of fMRI data per person). We characterized three functional subdivisions within the amygdala of each individual. We discovered that one subdivision is preferentially correlated with the default mode network; a second is preferentially correlated with the dorsal attention and fronto-parietal networks; and third subdivision does not have any networks to which it is preferentially correlated relative to the other two subdivisions. All three subdivisions are positively correlated with ventral attention and somatomotor networks and negatively correlated with salience and cingulo-opercular networks. These observations were replicated in an independent group dataset of 120 individuals. We also found substantial across-subject variation in the distribution and magnitude of amygdala functional connectivity with the cerebral cortex that related to individual differences in the stereotactic locations both of amygdala subdivisions and of cortical functional brain networks. Finally, using lag analyses, we found consistent temporal ordering of fMRI signals in the cortex relative to amygdala subdivisions. Altogether, this work provides a detailed framework of amygdala–cortical interactions that can be used as a foundation for models relating aberrations in amygdala connectivity to psychiatric symptoms in individual patients.
All-digital histopathology by infrared-optical hybrid microscopy
Authors: Schnell Martin , Mittal Shachi , Falahkheirkhah Kianoush , Mittal Anirudh , Yeh Kevin , Kenkel Seth , Kajdacsy-Balla Andre , Carney P. Scott , Bhargava Rohit
Published: February 2020

Significance

This study reports the ability to provide label-free molecular information from infrared (IR) spectroscopy via the ubiquitous optical microscope. Modeling the thermal-mechanical coupling of samples, we design, build, and validate an IR-optical hybrid (IR-OH) microscope that uses optical interferometry to measure the dimensional change in materials arising from spectral absorption. We show that the seamless compatibility of IR-OH with routine optical microscopy and with emerging computational ubiquity enables all-digital pathology with applications across the spectrum of biomedical science. IR-OH microscopy provides a means to retain the ease of use and universal availability of optical microscopy, add a wide palette of IR molecular contrast, and utilize emerging computational capabilities to change how we routinely handle, image, and understand microscopic tissue structure.
M2 amphipathic helices facilitate pH-dependent conformational transition in influenza A virus
Authors: Torabifard Hedieh , Panahi Afra , Brooks Charles L.
Published: February 2020

Significance

The influenza M2 protein is an integral membrane protein that transports protons across the viral envelope upon acid activation. M2 has become the target of numerous experimental and theoretical studies due to its important role in flu infection; however, there are still unresolved questions regarding the proton-conductance mechanism. In addition, these studies were mostly performed on constructs containing only the TM domain of the protein. We have applied explicit solvent CpHMD
MSλD
to the M2 construct containing the TM and AH domains, as well as the truncated M2. Our model provides a qualitative picture of pH-dependent conformational transitions in the M2 channel that suggests an important role of the AH on this transition and, consequently, on the proton-transport mechanism.
Formation of stable aggregates by fluid-assembled solid bridges
Authors: Seiphoori Ali , Ma Xiao-guang , Arratia Paulo E. , Jerolmack Douglas J.
Published: February 2020

When a colloidal suspension is dried, capillary pressure may overwhelm repulsive electrostatic forces, assembling aggregates that are out of thermal equilibrium. This poorly understood process confers cohesive strength to many geological and industrial materials. Here we observe evaporation-driven aggregation of natural and synthesized particulates, probe their stability under rewetting, and measure bonding strength using an atomic force microscope. Cohesion arises at a common length scale (∼5 μm), where interparticle attractive forces exceed particle weight. In polydisperse mixtures, smaller particles condense within shrinking capillary bridges to build stabilizing “solid bridges” among larger grains. This dynamic repeats across scales, forming remarkably strong, hierarchical clusters, whose cohesion derives from grain size rather than mineralogy. These results may help toward understanding the strength and erodibility of natural soils, and other polydisperse particulates that experience transient hydrodynamic forces.
Protection of cochlear synapses from noise-induced excitotoxic trauma by blockade of Ca
2+
-permeable AMPA receptors
Authors: Hu Ning , Rutherford Mark A. , Green Steven H.
Published: February 2020

Significance

Noise can cause excitotoxic trauma to cochlear synapses by triggering excessive release of the neurotransmitter glutamate from the auditory sensory hair cells. We report that a specific class of glutamate receptors, Ca
2+
-permeable α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) receptors (CP-AMPARs), is largely responsible for this trauma. Because cochlear synapses are heterogenous with respect to glutamate receptors, the observation that a specific class is responsible might explain the variability in susceptibility to noise among synapses. Selective blockade of CP-AMPARs prevents excitotoxicity and noise-induced cochlear synaptopathy, while other glutamate receptors continue to mediate neurotransmission and allow hearing.
Shape-preserving amorphous-to-crystalline transformation of CaCO
3
revealed by in situ TEM
Authors: Liu Zhaoming , Zhang Zhisen , Wang Zheming , Jin Biao , Li Dongsheng , Tao Jinhui , Tang Ruikang , De Yoreo James J.
Published: February 2020

Organisms use inorganic ions and macromolecules to regulate crystallization from amorphous precursors, endowing natural biominerals with complex morphologies and enhanced properties. The mechanisms by which modifiers enable these shape-preserving transformations are poorly understood. We used in situ liquid-phase transmission electron microscopy to follow the evolution from amorphous calcium carbonate to calcite in the presence of additives. A combination of contrast analysis and infrared spectroscopy shows that Mg ions, which are widely present in seawater and biological fluids, alter the transformation pathway in a concentration-dependent manner. The ions bring excess (structural) water into the amorphous bulk so that a direct transformation is triggered by dehydration in the absence of morphological changes. Molecular dynamics simulations suggest Mg-incorporated water induces structural fluctuations, allowing transformation without the need to nucleate a separate crystal. Thus, the obtained calcite retains the original morphology of the amorphous state, biomimetically achieving the morphological control of crystals seen in biominerals.
Whole-proteome tree of life suggests a deep burst of organism diversity
Authors: Choi JaeJin , Kim Sung-Hou
Published: February 2020

An organism tree of life (organism ToL) is a conceptual and metaphorical tree to capture a simplified narrative of the evolutionary course and kinship among the extant organisms. Such a tree cannot be experimentally validated but may be reconstructed based on characteristics associated with the organisms. Since the whole-genome sequence of an organism is, at present, the most comprehensive descriptor of the organism, a whole-genome sequence-based ToL can be an empirically derivable surrogate for the organism ToL. However, experimentally determining the whole-genome sequences of many diverse organisms was practically impossible until recently. We have constructed three types of ToLs for diversely sampled organisms using the sequences of whole genome, of whole transcriptome, and of whole proteome. Of the three, whole-proteome sequence-based ToL (whole-proteome ToL), constructed by applying information theory-based feature frequency profile method, an “alignment-free” method, gave the most topologically stable ToL. Here, we describe the main features of a whole-proteome ToL for 4,023 species with known complete or almost complete genome sequences on grouping and kinship among the groups at deep evolutionary levels. The ToL reveals 1) all extant organisms of this study can be grouped into 2 “Supergroups,” 6 “Major Groups,” or 35+ “Groups”; 2) the order of emergence of the “founders” of all of the groups may be assigned on an evolutionary progression scale; 3) all of the founders of the groups have emerged in a “deep burst” at the very beginning period near the root of the ToL—an explosive birth of life’s diversity.
The displacement field associated with the freezing of a melt and its role in determining crystal growth kinetics
Authors: Sun Gang , Hawken Alexander , Harrowell Peter
Published: February 2020

Significance

We demonstrate that an accurate estimation of the displacements associated with the transformation of liquid into crystal is necessary to explain the striking variations in the temperature dependence of the addition rate of liquid atoms to the growing crystal interface during freezing. An assignment algorithm, adapted from operations theory, is shown to provide a good estimate of these atomic displacements. As the assignment algorithm requires only initial and target locations, it is applicable to all forms of structural transformations. In resolving a fundamental feature of the kinetics of freezing, a phenomenon of central importance to material fabrication, this paper also provides the tools to open lines of research into the kinetics of structural transformation.
Listeria monocytogenesexploits host exocytosis to promote cell-to-cell spread
Authors: Dowd Georgina C. , Mortuza Roman , Bhalla Manmeet , Van Ngo Hoan , Li Yang , Rigano Luciano A. , Ireton Keith
Published: February 2020

The facultative intracellular pathogenListeria monocytogenesuses an actin-based motility process to spread within human tissues. Filamentous actin from the human cell forms a tail behind bacteria, propelling microbes through the cytoplasm. Motile bacteria remodel the host plasma membrane into protrusions that are internalized by neighboring cells. A critical unresolved question is whether generation of protrusions byListeriainvolves stimulation of host processes apart from actin polymerization. Here we demonstrate that efficient protrusion formation in polarized epithelial cells involves bacterial subversion of host exocytosis. Confocal microscopy imaging indicated that exocytosis is up-regulated in protrusions ofListeriain a manner that depends on the host exocyst complex. Depletion of components of the exocyst complex by RNA interference inhibited the formation ofListeriaprotrusions and subsequent cell-to-cell spread of bacteria. Additional genetic studies indicated important roles for the exocyst regulators Rab8 and Rab11 in bacterial protrusion formation and spread. The secretedListeriavirulence factor InlC associated with the exocyst component Exo70 and mediated the recruitment of Exo70 to bacterial protrusions. Depletion of exocyst proteins reduced the length ofListeriaprotrusions, suggesting that the exocyst complex promotes protrusion elongation. Collectively, these results demonstrate thatListeriaexploits host exocytosis to stimulate intercellular spread of bacteria.
Ecological drivers of bacterial community assembly in synthetic phycospheres
Authors: Fu He , Uchimiya Mario , Gore Jeff , Moran Mary Ann
Published: February 2020

In the nutrient-rich region surrounding marine phytoplankton cells, heterotrophic bacterioplankton transform a major fraction of recently fixed carbon through the uptake and catabolism of phytoplankton metabolites. We sought to understand the rules by which marine bacterial communities assemble in these nutrient-enhanced phycospheres, specifically addressing the role of host resources in driving community coalescence. Synthetic systems with varying combinations of known exometabolites of marine phytoplankton were inoculated with seawater bacterial assemblages, and communities were transferred daily to mimic the average duration of natural phycospheres. We found that bacterial community assembly was predictable from linear combinations of the taxa maintained on each individual metabolite in the mixture, weighted for the growth each supported. Deviations from this simple additive resource model were observed but also attributed to resource-based factors via enhanced bacterial growth when host metabolites were available concurrently. The ability of photosynthetic hosts to shape bacterial associates through excreted metabolites represents a mechanism by which microbiomes with beneficial effects on host growth could be recruited. In the surface ocean, resource-based assembly of host-associated communities may underpin the evolution and maintenance of microbial interactions and determine the fate of a substantial portion of Earth’s primary production.
The α-synuclein hereditary mutation E46K unlocks a more stable, pathogenic fibril structure
Authors: Boyer David R. , Li Binsen , Sun Chuanqi , Fan Weijia , Zhou Kang , Hughes Michael P. , Sawaya Michael R. , Jiang Lin , Eisenberg David S.
Published: February 2020

Aggregation of α-synuclein is a defining molecular feature of Parkinson’s disease, Lewy body dementia, and multiple systems atrophy. Hereditary mutations in α-synuclein are linked to both Parkinson’s disease and Lewy body dementia; in particular, patients bearing the E46K disease mutation manifest a clinical picture of parkinsonism and Lewy body dementia, and E46K creates more pathogenic fibrils in vitro. Understanding the effect of these hereditary mutations on α-synuclein fibril structure is fundamental to α-synuclein biology. We therefore determined the cryo-electron microscopy (cryo-EM) structure of α-synuclein fibrils containing the hereditary E46K mutation. The 2.5-Å structure reveals a symmetric double protofilament in which the molecules adopt a vastly rearranged, lower energy fold compared to wild-type fibrils. We propose that the E46K misfolding pathway avoids electrostatic repulsion between K46 and K80, a residue pair which form the E46-K80 salt bridge in the wild-type fibril structure. We hypothesize that, under our conditions, the wild-type fold does not reach this deeper energy well of the E46K fold because the E46-K80 salt bridge diverts α-synuclein into a kinetic trap—a shallower, more accessible energy minimum. The E46K mutation apparently unlocks a more stable and pathogenic fibril structure.
Acoustically powered surface-slipping mobile microrobots
Authors: Aghakhani Amirreza , Yasa Oncay , Wrede Paul , Sitti Metin
Published: February 2020

Significance

Untethered microrobots have significant applications in medical interventions such as targeted drug delivery. Here, we present an acoustically propelled microrobot that uses a fast and unidirectional surface-slipping locomotion strategy to navigate on both flat and curved surfaces. The three-dimensionally microprinted microrobot contains a trapped spherical air bubble to harness acoustic waves for propulsion at incredibly high speeds, up to 90 body lengths per second with body length of about 25 µm, and it can be steered by external magnetic fields. The proposed microrobot has a thrust force of about two to three orders of magnitude higher than that of microorganisms, such as algae and bacteria, which is sufficient for navigation inside vascular capillaries with blood flow.
Repair of a previously uncharacterized second host-range gene contributes to full replication of modified vaccinia virus Ankara (MVA) in human cells
Authors: Peng Chen , Moss Bernard
Published: February 2020

Significance

The highly attenuated vaccine vector MVA is an approved smallpox vaccine and is undergoing clinical trials as a vaccine vector for other infectious diseases. Although an inability to replicate in human cells contributes to the safety of MVA, the basis for its host restriction is not understood. Here we identify a host-range gene C16L/B22R, which is present as two copies in most orthopoxviruses but is inactivated in MVA. Repair of this gene allows replication of MVA in several tested human cell lines and, in combination with a second missing host-range gene C12L, restores full replication. Furthermore, a human cell line expressing both proteins is permissive for MVA. This knowledge may contribute to further engineering of MVA vaccines.
Parent coaching increases conversational turns and advances infant language development
Authors: Ferjan Ramírez Naja , Lytle Sarah Roseberry , Kuhl Patricia K.
Published: February 2020

Parental language input is one of the best predictors of children’s language achievement. Parentese, a near-universal speaking style distinguished by higher pitch, slower tempo, and exaggerated intonation, has been documented in speech directed toward young children in many countries. Previous research shows that the use of parentese and parent–child turn-taking are both associated with advances in children’s language learning. We conducted a randomized controlled trial to determine whether a parent coaching intervention delivered when the infants are 6, 10, and 14 mo of age can enhance parental language input and whether this, in turn, changes the trajectory of child language development between 6 and 18 mo of age. Families of typically developing 6-mo-old infants (
n
= 71) were randomly assigned to intervention and control groups. Naturalistic first-person audio recordings of the infants’ home language environment and vocalizations were recorded when the infants were 6, 10, 14, and 18 mo of age. After the 6-, 10-, and 14-mo recordings, intervention, but not control parents attended individual coaching appointments to receive linguistic feedback, listen to language input in their own recordings, and discuss age-appropriate activities that promote language growth. Intervention significantly enhanced parental use of parentese and parent–child turn-taking between 6 and 18 mo. Increases in both variables were significantly correlated with children’s language growth during the same period, and children’s language outcomes at 18 mo. Using parentese, a socially and linguistically enhanced speaking style, improves children’s social language turn-taking and language skills. Research-based interventions targeting social aspects of parent–child interactions can enhance language outcomes.
An algebraic perspective on abstract and concrete domains
Authors: Khatin-Zadeh Omid , Eskandari Zahra , Bakhshizadeh-Gashti Yousef , Vahdat Sedigheh , Banaruee Hassan
Published: February 2020

Looking at isomorphic constructs from an algebraic perspective, this article suggests that every concrete
construct is understood by reference to an underlying abstract schema in the mind of comprehender. The complex form of every
abstract schema is created by the gradual development of its elementary form. Throughout the process of cognitive development, new
features are added to the elementary form of abstract schema, which leads to gradual formation of a fully-developed abstract
schema. Every developed abstract schema is the underlying source for understanding an infinite number of concrete isomorphic
constructs. It is suggested that the process of the mapping of base domain (base construct) unto target domain (target construct)
is conducted and mediated by an abstract domain. This abstract domain, which is free from concrete features of base and target, is
isomorphic to both base and target domains. To describe the mediatory role of this abstract domain, it might be argued that the
chain process of understanding a less familiar domain in terms of a relatively more familiar domain (salience imbalance model)
cannot continue infinitely. This chain must stop at some point. This point is the abstract domain, which is isomorphic to base and
target domains.
The role of talker variability in the perceptual learning of Mandarin tones by American English
listeners
Authors: Silpachai Alif
Published: February 2020

Research on segmentals has suggested that a key component of High Variability Phonetic Training (HVPT) is high
talker variability. However, the extent to which high talker variability improves perception of tones is unclear. This study
examined the effects of high talker variability on the perception of Mandarin tones (Tones 1–4) by English-speaking listeners. A
training paradigm that used multiple talkers (multitalker group) was compared with a paradigm that used one talker (single-talker
group). The results showed that the multitalker group outperformed the single-talker group, and they retained their learning
better than the single-talker group did for 6 months. Neither group, however, improved their perception of Tone 1 or generalized
their learning of monosyllables to disyllables. The results suggest that although high talker variability can effectively improve
tone perception, it does not improve the perception of more tone categories or yield generalization of learning to more contexts
compared to low talker variability.
The literary genre effect
Authors: Gavaler Chris , Johnson Dan
Published: February 2020

We test the literariness of genre fiction with an empirical
study that directly manipulates both intrinsic text properties and extrinsic
reader expectations of literary merit for science-fiction and narrative-realism
stories. Participants were told they were going to read a story of either low or
high literary merit and then read one of two stories that were identical except
for one genre-determining word. There were no differences between the
science-fiction and narrative-realism versions of the story in literary merit
perception, text comprehension, or inference effort for theory of mind and plot.
Participants did, however, exert more theory-of-world effort (i.e.,
world-building) for the science-fiction version. The more inference effort
science-fiction readers dedicated to theory of world, the more cognitively and
emotionally engaged they were. These results contradict the assumption that
science fiction cannot achieve literariness and instead demonstrate a “literary
genre effect.”
Acoustic guided wave detection of grounding rod corrosion: equivalent circuit model and implementation
Authors: Durham Nicholas , Zhao Junhui , Bridges Gregory , Thomson Douglas
Published: February 2020

Acoustic pulse-echo systems, are effective for corrosion damage detection in buried individual ground rods without any need for excavation. In electric power distribution systems there are large numbers buried ground rods are used in substations to form a grounding networks that is critical for the protection of equipment and personnel working in the vicinity of the substation. Over time, these grounding rods will corrode and cease to provide adequate protection. In this work, we present an equivalent circuit model (ECM) for acoustic pulse-echo corrosion detection systems. The circuit model was used to develop a transducer configuration that effectively launches longitudinal acoustic waves that can accurately detect position and damage severity. We show that our model correctly predicts the temporal response from both undamaged rods and rods with machined simulated corrosion pits. The circuit model also accounts for loss, and the results show strong agreement with simulated soil-loss in laboratory experiments. Evidence of wave mode conversion is found in experimental data that is not captured by the model. Preliminary field measurements of copper-clad steel grounding rods are presented that show strong similarities to modeled results. This ECM is a promising basis for further development of pulse-echo systems for corrosion detection and may be useful for future tomographic analysis of field measurements.
Present status of HIRFL complex in Lanzhou
Authors: Yuan Y J , Gao D Q , Ma L Z , Mao L J , Mao R S , Meng J , Su Y W , Sun L T , Wang Y Y , Wu J X , Xu Z , Yang J C , Yang W Q , Yao Q G , Yin X J , Zhang B , Zhang W , Zhou Z Z , Zhao H W , Xiao G Q , Xia J W
Published: February 2020

Heavy Ion Research Facility in Lanzhou (HIRFL) is a cyclotron, synchrotron and storage ring accelerator complex, which accelerates ions of hydrogen to uranium from low to medium energy. Since the complete of HIRFL-CSR project in 2008, under the support from CAS, efforts have been put to improve the infrastructure for machine performance, including improvement of EMC environments, power distribution stations, PS stations, cooling water system, RF system of cyclotrons and adoption of EPICS control system, etc. New generation SC ECR source (SECRAL-II) with high performance is put into operation. Experiments of electron cooling with pulsed electron beam are performed for the first time. Stochastic cooling and laser cooling are realized in CSRe. The performance of RIBLL2 and CSRe are gradually improved. The isochronous mode of CSRe for precise atomic mass measurements is well studied and reaches state-of-art mass resolution of storage rings. The operation status and enhancement plan of HIRFL will be briefly reported in this paper.
Commissioning of China ADS demo Linac and baseline design of CiADS project
Authors: Liu Shuhui , Wang Zhijun , Chen Weilong , Dou Weiping , Jia Huan , Qin Yuanshuai , He Yuan , Zhao Hongwei
Published: February 2020

China Accelerator Driven Subcritical System (C-ADS) program was launched in China in 2011. In the first five-year phase, a 25 MeV demo linac has been successfully built to demonstrate the key technologies of the driven linac. Beam commissioning activities have been carried out to study the high-power beam physics. Followed by the previous phase, China Initiative Accelerator Driven Subcritical System (CiADS) is approved contain a superconducting proton linac with 500 MeV and 5 mA. In this paper, the commissioning results of the demo linac and the beam dynamics design of CiADS linac based on commissioning experiences are presented.
First acceleration of heavy ion beams with a superconducting continuous wave HIM/GSI CW-linac
Authors: Basten M. , Aulenbacher K. , Barth W. , Busch M. , Dziuba F. , Gettmann V. , Heilmann M. , Kürzeder T. , Lauber S. , Miski-Oglu M. , Podlech H. , Rubin A. , Schnase A. , Schwarz M. , Yaramyshev S.
Published: February 2020

In the future a new superconducting (sc) continuous wave (cw) high intensity heavy ion Linac should provide ion beams with a max. beam energy above the coulomb barrier for the Super Heavy Element (SHE) program at GSI Helmholtzzentrum für Schwerionenforschung. Key features of this new Linac are the acceleration of different ions from protons to uranium as well as a smooth energy variation from 3.5 to 7.3 MeV/u for design ions with a mass-to-charge ratio A/q = 6 and even above for lighter ions. As a first step a newly developed superconducting 15-gap Crossbar H-cavity (CH-cavity) operated at 217 MHz has been successfully tested with heavy ion beam up to the design beam energy of 1.85 MeV/u for the first time. The design energy gain of 3.5 MV within a length of less than 70 cm has been validated with heavy ion beams of up to 1.5 pμA. The measured beam parameters showed excellent beam quality, while a dedicated beam dynamics layout provides beam energy variation between 1.2 and 2.2 MeV/u. The beam commissioning is a milestone of the R&D work of Helmholtz Institute Mainz (HIM) and GSI in collaboration with Goethe University Frankfurt (GUF) and the first step towards a sc heavy ion cw-Linac with variable beam energy. The first tests under cryogenic conditions of the next two CH-cavities have already been started at GUF in a vertical cryostat. The results of the first successful heavy ion beam acceleration with a superconducting CH-cavity will be presented.
DESIGN AND BEAM COMMISSIONING OF THE LEAF-RFQ
Authors: Lu Liang , He Tao , Yang Lei , He Yuan , Zhao Hongwei , Xing Chaochao , Zhai Yuhan , Shi Longbo , Sun Liepeng , Li Jia , Xia Qianxu
Published: February 2020

An 81.25 MHz continuous wave (CW) radio frequency quadrupole (RFQ) accelerator has been designed and fabricated for the Low Energy Accelerator Facility (LEAF) by the Institute of Modern Physics (IMP) of the Chinese Academy of Science (CAS). The operation frequency is 81.25 MHz and the inter-vane voltage is a constant of 70 kV. It took about 44 hours continuous conditioning to reach RF power of 75 kW which is 1.1 time of the maximum designed value, and the successful CW acceleration of 150 eµA He+ beam to the designed energy of 0.5 MeV/u was already done. The results of the low power test, the RF conditioning and the beam acceleration will be reported in this paper.
Cryogenic test of the FRIB superconducting magnets at IMP
Authors: Yang Wenjie , Wu Beimin , Ni Dongshen , Wu Wei , Mei Enming , Ma Lizhen
Published: February 2020

The superconducting magnets of the Facility of Rare Isotope Beams (FRIB) are used to focus and steer the heavy ion beams of the driver linac. All the magnets are designed as a solenoid with bucking coils to suppress the stray field, and all the magnets have superconducting dipole correctors to steer both horizontal and vertical field. Two types of magnets have been manufactured in China, and some of them have been tested at Institute of Modern Physic (IMP). This paper describes the test system and magnetic axis measurement method. We also present a summary of the measurement process and test results of the magnetic performance for the magnets.
Multi-physics analysis and experiment of a CW four-rod RFQ
Authors: Li Z S , Xia J W , Yuan Y J , Yang J C , He Y , Yang Y Q , Xu Z , Cong Y , Meng J , Jing L , Du H , Wang Z J , Zhang Y , Wang H N , Li X N , Wang K D , Xie W J , Wei Y , Xie H M , Xu X W , Shen G D , Kong Q Y , Yin X J , Wu J X , Lu Y R , Zhu K
Published: February 2020

The new injector SSC-LINAC is under design and construction to improve the efficiency and intensity of beams for the Separated-Sector Cyclotron (SSC). This will be accomplished with a normal conducting radio-frequency quadrupole (RFQ) accelerator. To match with the SSC, the RFQ must be operated on Continuous Wave (CW) mode with a frequency of 53.667 MHz. A four-rod structure was adopted for small dimensions of the cavity. While, it was a huge challenge on CW mode. A multi-physics theoretical analysis, including RF, thermal, structural and frequency shift coupling analysis, have been completed in response to the safe and stable operation of the RFQ. The experimental measurement of frequency shift has been also completed, which is consistent with the simulation. In this paper, the results of theoretical analysis and experiment are reported in detail.
Nb Sputtered 325 MHz QWR Cavities for CIADS
Authors: Pan F. , Tan T. , Xiong P. , Guo H. , Zhang C. , Jiang T. , He Y. , Li Z. , Wang H.
Published: February 2020

The possibility for adopting niobium thin film coated copper (Nb/Cu) quarter wave resonators (QWRs) in the low energy section of CiADS project[1] is being evaluated. Comparing with bulk niobium cavities, the Nb/Cu cavities feature a much better thermal and mechanical stability at 4.5 K. Two 325 MHz Nb/Cu QWR cavities have been fabricated at IMP, to demonstrate whether the niobium coated copper cavity technique can meet the requirements of CiADS. The cavity is coated with biased DC diode sputtering technique. This paper covers resulting film characters, vertical tests with the evolution of the sputtering process, and improvements to mitigate issues we met.
Traces of marine activity in the history of medieval Vologda
Authors: Adamenko O N , Yashina O V , Bashnin N V
Published: February 2020

Paleozoological study of archaeological findings from the excavations of Vologda settlement (12th–15th centuries) revealed information about trade and trade links between Vologda and the Arctic region. The existence of such links in the Middle Ages and the Modern Age is also confirmed by museum collections and written sources that contain information about the participation of residents Vologda in long-distance marine expeditions to the Arctic region.
Survival of indicator species of the mammoth fauna large mammals in the Holocene of Yakutia (East Siberia, Russia)
Authors: Boeskorov G G
Published: February 2020

Global climate change at the end of the Pleistocene led to extinction across the huge territories of the Northern Hemisphere of indicator species of large mammals of the mammoth fauna. Undoubtedly, in some more densely populated regions, the mammoth fauna underwent pressure from Upper Paleolithic humans hunting activity. Previously it was thought that the megafauna of the “Mammoth complex” had become extinct in the territory of Yakutia by the beginning of the Holocene. However, the latest data indicate that extinction of the mammoth fauna was significantly delayed in the north of Eastern Siberia. Radiocarbon data show that wild horses inhabited the north of Yakutia during 5300–2200 cal yr BP. Musk oxen lived here about 3400 – 2600 cal yr BP. Some bison remains from Yakutia belong to the early Holocene. The following circumstances could have facilitated the survival of representatives of the mammoth fauna in Yakutia. The cool, dry climate in this region is favorable to steppe associations, the habitats of these mammals. The small number of Stone Age hunting tribes in the northern part of Yakutia was probably another factor that contributed to the survival of some mammoth fauna representatives.
Effect of insolation variations on vegetations of the Eurasian subarctic during the Holocene
Authors: Kuznetsov E , Galimov A , Shalaumova J , Borodin A
Published: February 2020

Variation of the insolation is one of the global factors which determine the Earth’s climate. Multi-periodic variations of the insolation determine the cyclicity of the Earth’s climate. The aim of the investigation is the estimation of the insolation variations influence on vegetations of the Urals and West Siberia subarctic during the Holocene. The calculation of insolation in the Eurasian Subarctic for the Holocene is carried out based on the solution La2004 for the long-period evolution of the Earth’s orbit. We have estimated the insolation for the latitudes from 55° to 70° N. We have considered the mean daily and mean monthly insolation over 12 ka BP. We assess changes of the insolation in the Eurasian subarctic under the influence of such factor as the topography evolution. The surface topography was analyzed for the recent period (in the Urals and West Siberia) and the Pliocene epoch (in West Siberia). An assessment of the difference in the corresponding digital elevation models showed that the subsidence of the crust took place in West Siberia (the median value of the difference between the digital elevation models was 230.7 m above sea level). The intensity of erosion processes increased in a southerly direction. We have shown that an increase in the number of autumn’s months with high insolation correlates with the taiga biome 4 thousand years ago to wider territories than 8 thousand years ago.
Diatom-inferred palaeolimnological changes in a small lake in the context of the Holocene Baltic Sea transgressions: a case study of Lake Goluboye, Karelian Isthmus (NW Russia)
Authors: Ludikova A V , Shatalova A E , Subetto D A , Kublitskiy Yu A , Rosentau A , Hang T
Published: February 2020

A sedimentary diatom record of Lake Goluboye, Karelian Isthmus (NW Russia) revealed two transgressive stages of the Baltic: the Ancylus Lake and the Litorina Sea, followed by two “small-lake” stages. During the Ancylus Lake transgression, a shallow bay of the Ancylus Lake existed in the Lake Goluboye basin, and species-rich benthic-dominated diatom assemblages formed in oligotrophic, low-mineralisation environments. The isolation from the Ancylus basin took place after ca. 9800 cal. yrs BP, when a small nutrient-rich lake formed in the basin. Two Litorina Sea transgressive phases were inferred from the diatom record of Lake Goluboye, both characterised with similar low-salinity environments. Such a weak signal of the marine transgression, compared with the other coastal sites in the Karelian Isthmus, might have resulted from the sheltered position of the lake. Our data also suppose that the maximum transgression level in the study area was lower than has previously been suggested. With the termination of the Litorina transgression shallow-water conditions with extensive macrophytes growth was established in the lake. Before ca. 4800 cal. yrs BP nutrient-rich small-lake conditions, similar to the post-Ancylus stage, became established.
Preliminary data on formation and depositional environments of lake Chaika in the central part of the Curonian Spit (Kaliningrad region, Russia, South-Eastern Baltic)
Authors: Napreenko M G , Orlov A V , Napreenko-Dorokhova T V , Subetto D A , Sosnina I A
Published: February 2020

Lake Chaika is the only major water body present in the sand barriers of the entire territory of South-Eastern Baltic shoreline. The article provides new insights into the formation of Lake Chaika, based on data acquired through a lithological investigation of the lake sediment core combined with an organic matter content analysis, a macrofossil analysis, a radiocarbon AMS-dating and a bathymetric survey. The study revealed that Lake Chaika was formed around 500 years ago. The kettle of the lake appears to have not been submerged during the Littorina transgressions. During the mid-late Holocene, the kettle of the lake was occupied by the peat-forming ecosystems of alder carrs and sedge fens with scattered alder. The accumulation of ligneous and sedge peat occurred. The sand horizon, separating the gyttja layer from peat deposits, is considered to be a time marker for the so-called “sand disaster”, which began in the study site 200-250 years earlier than in the main territory of the Curonian Spit. There are three main formation phases of the lake’s ecosystem: the period of carrs (5390–510 cal. yr BP), the “sand disaster” period (≈550–500 cal. yr BP) and the proper lake period (500 cal. yr BP – present time).