bluuebunny/crossref_metadata_2025 huggingface dataset:
Revisiting the paleomagnetism of Muong Nong layered tektites: Implications for their formation process
Authors: Gattacceca Jérôme , Rochette Pierre , Quesnel Yoann , Singsoupho Sounthone
Published: July 2021

Among Australasian tektites, the so‐called Muong Nong tektites stand out for their peculiar layering and blocky aspect. Although the source crater for the Australasian tektites is not known, Muong Nong tektites are generally considered as a relatively proximal ejecta. The mechanism responsible for the formation of the layering has been a matter of debate. In this work, we revisit the paleomagnetism of Muong Nong tektites. They retain a thermoremanent magnetization acquired during cooling below 585 °C in the presence of the ambient geomagnetic field, and carried magnetite in most samples, although at least one sample containing metallic iron was detected. The inclination of the paleomagnetic direction with respect to the layering plane clusters around 18 ± 12°, compatible with the inclination of the geomagnetic field for this latitude at the time of impact. This indicates that the layering of the Muong Nong tektites was subhorizontal while they were cooling below 585 °C. The preferred scenario for the formation of the layering of layered tektite is therefore by horizontal shear in pools or sheets of molten material.
Neutron capture 128Xe and 129Xe in the San Juan mass of the Campo del Cielo IAB iron meteorite: Evidence for a high fluence of thermalized neutrons
Authors: Pravdivtseva O. , Varela M. E. , Meshik A. , Campbell A. J. , Saavedra M. , Topa D.
Published: July 2021

The petrographic study of the San Juan A2 polished section demonstrated textural and compositional similarities with the Campo del Cielo IAB iron meteorite, with trace element abundances in metal following the pattern of bulk Campo del Cielo. Xenon, neon, and helium isotopic compositions have been measured in radial graphite rims, massive graphite inclusions, fine‐grained graphite aggregates, cliftonite, and platy graphite. Two silicate inclusions and two areas of metal were also analyzed. 3He/4He versus 4He/21Ne data for San Juan metal plot next to the values reported for the El Taco fragment of Campo del Cielo, supporting San Juan being a part of the Campo del Cielo meteorite shower. Based on the Ne isotopic composition of its components, and the observed correlation between 128Xe and 129Xe, the San Juan A fragment of Campo del Cielo was well shielded from the primary galactic cosmic ray high‐energy irradiation. Its size allowed the secondary neutrons to be fairly well thermalized, receiving an equivalent (normalized to the research reactor with highly thermalized neutron spectrum) fluence of thermal and epithermal neutrons of 6.6 × 1017 n cm−2. Considering 1.8 × 108 years single‐stage and constant exposure geometry irradiation history for Campo del Cielo, and assuming the identical neutron flux spectra for the research reactor and Campo del Cielo, the average thermal equivalent neutron flux for San Juan is about 1.2 × 102 n cm−2 s−1. Xe isotopic composition in the radial graphite rims and platy graphite shows evidence of live 129I in San Juan and is consistent with a mixture of iodine‐derived and tellurium‐derived Xe.
Multispectral imaging and hyperspectral scanning of the first dissection of core 73002: Preliminary results
Authors: Sun Lingzhi , Lucey Paul G. , Flom Abigail , Ferrari‐Wong Chiara , Zeigler Ryan A. , Gross Juliane , Petro Noah E. , Shearer Charles K. , McCubbin Francis M. ,   The ANGSA Science Team
Published: July 2021

We measured the multispectral images and a hyperspectral profile during the first dissection pass of core 73002, and here, we present preliminary results. Both multispectral images and hyperspectral data show systematic darkening and reddening from bottom to top of the core, indicating an increasing maturity from the subsurface to surface soils. Our estimated FeO and TiO2 abundances are 9 (±1) wt% and 1.8 (±0.5) wt%, and their homogeneous distributions imply no compositional stratigraphy was sampled by core 73002. The in situ regolith reworking depth is about 14 cm as inferred from the optical maturity (OMAT) profile, corresponding to a time range of about 61 million years. Mineralogy and Mg# (molar Mg/[Mg+Fe]) calculated using hyperspectral data and radiative transfer modeling show as expected the core is dominated by plagioclase and low‐Ca pyroxene, and the average Mg# is 61 (±10). Our work shows that spectroscopy has a great potential to be applied in the preliminary examination of future extraterrestrial samples from outside of the glovebox.
Fathers and grandmothers experiences participating in nutrition peer dialogue groups in Vihiga County, Kenya
Authors: Thuita Faith , Mukuria Altrena , Muhomah Teresia , Locklear Kamryn , Grounds Samantha , Martin Stephanie L.
Published: July 2021

Grandmothers and fathers are key influencers of maternal and child nutrition and are increasingly included in interventions. Yet, there is limited research exploring their experiences participating in interventions. This study reports on findings from a qualitative process evaluation of a quasi‐experimental study that we conducted with grandmother and father peer dialogue groups to support maternal, infant and young child feeding practices in western Kenya. The aim was to explore grandmother and father experiences participating in interventions and how participation influences care and feeding practices. Grandmother and father peer educators received training to facilitate discussions about maternal and child nutrition, HIV and infant feeding, family communication, and family members' roles. Father peer educators also received training on gender inequities and power dynamics. In the original quasi‐experimental study, the intervention was associated with increased social support and improvements in some complementary feeding practices. The process evaluation explored participants' experiences and how participation influenced infant care and feeding practices. We used Atlas.ti to thematically analyse data from 18 focus group discussions. The focus group discussions revealed that grandmothers and fathers valued their groups, the topics discussed and what they learned. Grandmothers reported improved infant feeding and hygiene practices, and fathers reported increased involvement in child care and feeding and helping with household tasks. Both described improved relationships with daughters‐in‐law or wives. This study highlights the importance of engaging influential family members to support child nutrition and identifies factors to build cohesion among group members, by building on grandmothers' roles as advisors and expanding fathers' roles in nutrition through gender transformative activities.
European oak chemical diversity – from ecotypes to herbivore resistance
Authors: Bertić Marko , Schroeder Hilke , Kersten Birgit , Fladung Matthias , Orgel Franziska , Buegger Franz , Schnitzler Jörg‐Peter , Ghirardo Andrea
Published: July 2021

Climate change is increasing insect pressure and forcing plants to adapt. Although chemotypic differentiation and phenotypic plasticity in spatially separated tree populations are known for decades, understanding their importance in herbivory resistance across forests remains challenging.

We studied four oak forest stands in Germany using nontarget metabolomics, elemental analysis, and chemometrics and mapped the leaf metabolome of herbivore‐resistant (T‐) and herbivore‐susceptible (S‐) European oaks (Quercus robur) toTortrix viridana, an oak pest that causes severe forest defoliation.

Among the detected metabolites, we identified reliable metabolic biomarkers to distinguish S‐ and T‐oak trees. Chemotypic differentiation resulted in metabolic shifts of primary and secondary leaf metabolism. Across forests, T‐oaks allocate resources towards constitutive chemical defense enriched of polyphenolic compounds, e.g. the flavonoids kaempferol, kaempferol and quercetin glucosides, while S‐oaks towards growth‐promoting substances such as carbohydrates and amino‐acid derivatives.

This extensive work across natural forests shows that oaks' resistance and susceptibility to herbivory are linked to growth‐defense trade‐offs of leaf metabolism. The discovery of biomarkers and the developed predictive model pave the way to understandQuercus robur's susceptibility to herbivore attack and to support forest management, contributing to the preservation of oak forests in Europe.
Two‐step Two‐intermediate Photorelease Bolm‐McCulla Reaction: Dual Release of Nitrene and Atomic Oxygen Reactive Intermediates
Authors: Rashid Mahir , Baker Devora D. , Greer Alexander
Published: July 2021

This article is a highlight of the paper by Isor et al. in this issue of Photochemistry and Photobiology. It describes the photolysis of a dibenzothiophene sulfoximine (bearing N‐phenyl imino and S‐oxide groups) to produce two reactive intermediates in tandem. The sulfoximine undergoes a S–N and S–O photocleavage to release phenyl nitrene and atomic oxygen [O(3P)]. The phenyl nitrene dimerizes to azobenzene or is trapped by diethylamine to reach an azepine. From there, atomic oxygen arises in a secondary photolysis of dibenzothiophene sulfoxide. A computational analysis also reveals that the S–N bond is labile for initial nitrene release, with the secondary release of atomic oxygen by S–O cleavage. Whether future sulfoximine scaffolds can produce the reverse order release of O(3P) then nitrene, or release both simultaneously, is yet to be established. Nonetheless, molecules with dual‐intermediate release, such as coupled photoaffinity labeling and cellular oxidation, are worth pursuing.
Prevalence of periapical abscesses in patients with systemic lupus erythematosus
Authors: Rotstein Ilan , Katz Joseph
Published: July 2021

Aims

To assess the prevalence of periapical abscesses in patients with systemic lupus erythematosus (SLE), and to evaluate the effect of glucocorticoids (GCs) used to treat SLE, on the prevalence of such lesions.

Methods

Integrated data of hospital patients was used. Data from the corresponding diagnosis codes for SLE and periapical abscess was retrieved by searching the appropriate query in the database. The odd ratio (OR) of periapical abscesses and its association with SLE and intake of GCs were calculated and analyzed statistically.

Results

The prevalence of periapical abscesses in patients treated with GCs was 1.5% compared to 0.39% in patients who were not treated with GCs. The OR for periapical abscesses in patients treated with GCs was 2.53 compared with OR of 0.66 in patients not treated with GCs. The differences were statistically significant (p < .0001). The prevalence of periapical abscesses in patients with SLE was 1.88%. The OR was 3.18 and the difference statistically significant (p < .0001). Conclusions: Under the conditions of this study, it appears that the prevalence of periapical abscesses is higher in patients with SLE. Patients receiving GCs therapy, either for SLE or for other conditions, may present higher prevalence of periapical abscesses
Persistent activation of the mammalian target of rapamycin signalling pathway in cutaneous squamous cell carcinomas in cats
Authors: Sanz Ressel Berenice L. , Massone Adriana R. , Barbeito Claudio G.
Published: July 2021

Background

Cutaneous squamous cell carcinoma (CSCC) represents the most common malignant tumour of the feline skin. Emerging evidence suggests that the phosphatidylinositol 3‐kinase/Akt/mammalian target of rapamycin (PI3K/Akt/mTOR) signalling pathway may represent a potential target for pharmacological intervention in human and canine CSCC.

Hypothesis/Objectives

The present study aimed to explore the expression pattern and status of activation of relevant signalling proteins of the PI3K/Akt/mTOR signalling pathway in feline CSCC.

Methods and materials

The expression of pEGFRTyr1068, pAktSer473, pS6Ser235/236 combined with Ki‐67, and the tumour suppressor protein PTEN was evaluated by immunohistochemical analysis in 45 samples of feline CSCC, using a tissue microarray.

Results

The immunodetection using phosphospecific antibodies to detect the activated forms of signalling proteins showed that the PI3K/Akt/mTOR signalling pathway is frequently activated in feline CSCCs, and may be independent of the activation of EGFR. The results also showed that PTEN expression is not significantly altered in feline CSCCs.

Conclusions and clinical importance

Our study shows that the persistent activation of the PI3K/Akt/mTOR signalling pathway represents a key event in feline CSCC, pointing to this signalling pathway being a potential therapeutic target in feline patients with CSCC.
Ultrasonographic and CT diagnosis of a complete splenic duplication with right splenic torsion and presumed regional splenic vein hypertension in a dog
Authors: Battiato Pierantonio , Salgüero Raquel , Specchi Swan , Longo Maurizio
Published: July 2021

An 8‐year‐old mixed breed dog, was referred for lethargy, abdominal discomfort, hematemesis, and melena. Abdominal ultrasound revealed mineralization of the “right splenic vein” with collateral spiraling and a suspected splenic duplication. Computed tomography confirmed the duplication along with torsion of the splenic pedicle. Exploratory laparotomy confirmed the splenic torsion associated with congestion of the gastrointestinal vessels, indicative of a chronic onset of secondary regional splenic vein hypertension.
The potential of Myosoton aquaticum extracts and compounds to control barnyardgrass (Echinochloa crus‐galli)
Authors: Yang Haona , Tang Yi , Wang Lifeng , Guo Yanan , Luo Dingfeng , Wu Lamei , Deng Xile , Li Xiaogang , Bai Lianyang
Published: July 2021

Although cover crops are widely used for weed suppression in the agroecosystem, little research is available regarding the possibility that the decomposed weed solution may control weeds. In this study, we tested the allelopathic effect of decomposed weed solution on barnyardgrass (Echinochloa crus‐galli). In two separate tests, we found that the solution of decomposed Myosoton aquaticum completely suppressed the germination of barnyardgrass seeds at a concentration of 20 g l‐1. We then isolated and identified the predominant inhibitory substance in the decomposed M. aquaticum solution. The solution was subjected to organic solvent extraction and then separated on a silica gel column before the final identification of its components by high‐performance liquid chromatography‐tandem mass spectrometry (HPLC‐MS/MS). Dihydrocoumarin was isolated from the M2 and M3 fractions using a bioassay‐guided method and was found to be the most active of eleven candidate allelochemical compounds. Dihydrocoumarin is typically used as a food additive. In this study, barnyardgrass germination was completely inhibited when treated with dihydrocoumarin at 1 g l‐1, and its root and shoot growth were significantly inhibited at an application rate of 0.005 g l‐1. Dihydrocoumarin showed highly efficient inhibition of root and shoot growth in barnyardgrass at low concentrations compared with coumarin. These findings show that weeds may be used as cover crops to provide allelochemicals for weed suppression and that dihydrocoumarin has the potential to be used as a bioherbicide.
Assessment of crab fishermen's exposure to rabies virus in a typical Amazonian community
Authors: de Paula Silva Nailde , de Andrade Elane de Araújo , Cardoso Denis , Guimarães Ruth Cavalcante Silva , Silva Mateus Borges , Nascimento Kelly Karoline Gomes , Xavier Diego de Arruda , Abel Isis
Published: July 2021

Outbreaks of human rabies transmitted by hematophagous bats occurred in 2018 in Pará state, Brazil, eastern Amazon, after 12 years of no record of the disease. Thus, it is necessary to understand the epidemiological characteristics of these attacks to protect the local population. This study aimed to characterize the bat bite populations in the municipality of São João da Ponta, Pará State, Brazil, in 2013–2015. The Notifiable Diseases Information System (SINAN) database was used to identify the five individuals who sought medical care during the study period (seeds). Other individuals who were attacked during the same period but did not seek medical care (n = 61) were reached by snowball sampling, and a descriptive analysis was performed based on information obtained from questionnaires. Majority of the interviewees were men (92.4%; 61/66) and adults aged 20–50 years (69.9%; 46/66) and had <4 years of formal school education (86.3%; 57/66). Additionally, most of them were rural residents (92.4%; 61/66) and crab fishermen (79.3%; 53/66). The interviewees (92.4%; 61/66) identified mangroves of the Mãe Grande de Curuçá extractive reserve, where groups of fishermen sometimes gather for several days for crab fishing, often living in improvised dwellings without walls and covered by tarps or straw (88.8%; 56/66), conducive to attacks by vampire bats. Overall, 42.4% (28/66) of the participants had been bitten more than four times throughout their life. The median number of attacks over the participant's lifetime was 3.11 (range, 1–23). Participants were unaware of the risk of contracting rabies from the bite (95.4%; 65/66). These results suggest that vampire bat attacks are essentially an occupational hazard in the study region. Moreover, for each reported attack, there were at least 12.2 unreported cases. Thus, the study highlights the need to develop strategies for prophylactic treatment of this population.
Deprived Sector Lending and Non-Performing Loans in Nepal
Authors: Oli Sudan Kumar
Published: July 2021

This study investigates the empirical impact of deprived sector lending on the nonperforming loans of commercial banks in Nepal using secondary data collected from 27 commercial banks from the fiscal year 2009 to 2018 with 262 observations. The study employed the OLS regression method for the robustness test of the result. The study establishes empirical relation between deprived sector lending and nonperforming loan of banks which was the major motivation of this study. The basic regression result shows that beta coefficient of DSL is negative which indicates higher the ratio of deprived sector lending, the lower would be the NPL and vice-versa. Similarly, this study also examines the DSL movement's impact on NPL. The result shows that the beta coefficient of ∆DSL is significantly negative with ∆NPL. This indicates that the higher the growth of DSL, the lower would be NPL growth and vice-versa. This shows that the influence of DSL is very low as per this empirical result. Overall, the study shows there is an inverse relationship between deprived sector lending and nonperforming loan of banks. The result indicates that the remark of commercial bank’s on the deprived sector lending policy of NRB is not true. The operational cost might increase with direct lending to deprive sector and that leads to decrease in the bank’s overall profit but not increases their NPL.
Construcción de triángulos, recurso para impulsar un ambiente de indagación
Authors: Camargo-Uribe Leonor , Martínez-Mora Eliana
Published: July 2021

Este artículo de investigación presenta una vía para involucrar a estudiantes en ambientes de indagación en donde exploren, conjeturen, justifiquen y comuniquen sus hallazgos, al resolver problemas de construcción geométrica con apoyo de GeoGebra. Para ello, se empleó la metodología experimento de diseño, con estudiantes de 10 a 12 años, para poner la vía en funcionamiento y evaluar su efectividad. Se concluye que el reto de promover tal ambiente va más allá del diseño de situaciones problema. Se requiere un cambio en la cultura de la clase, promovido principalmente por el profesor, para generar un espacio colectivo de participación.
Lecturas de etnografías colaborativas con niñas, niños y jóvenes en contextos educativos latinoamericanos
Authors: Guerrero Alba Lucy , Milstein Diana Judit
Published: July 2021

Presentamos un análisis de etnografías colaborativas con la participación de niñas,niños y jóvenes(NNJ). Estos estudios  fueron realizados en contextos escolares diversos de Argentina,Ecuador y México,con los cuales nos proponemos mostrar cómo es posible desarrollar etnografías educativas entre adultos y niños sobre fenómenos sociales y culturales de sus vidas cotidianas,sus memorias,sus emociones, y dar cuenta de aprendizajes que trascienden y enriquecen los conocimientos escolares. Metodológicamente, realizamos una lectura analítica sobre cuatro etnografías seleccionadas de un estado del arte previamente desarrollado sobre investigaciones colaborativas con NNJ. Este análisis visibiliza cómo las etnografías realizadas con NNJ aportan al campo de la investigación educativa.
Modeling the effects of dynamic range compression on signals in noise
Authors: Corey Ryan M. , Singer Andrew C.
Published: July 2021

Hearing aids use dynamic range compression (DRC), a form of automatic gain control, to make quiet sounds louder and loud sounds quieter. Compression can improve listening comfort, but it can also cause unwanted distortion in noisy environments. It has been widely reported that DRC performs poorly in noise, but there has been little mathematical analysis of these noise-induced distortion effects. This work introduces a mathematical model to study the behavior of DRC in noise. By making simplifying assumptions about the signal envelopes, we define an effective compression function that models the compression applied to one signal in the presence of another. Using the properties of concave functions, we prove results about DRC that have been previously observed experimentally: that the effective compression applied to each sound in a mixture is weaker than it would have been for the signal alone; that uncorrelated signal envelopes become negatively correlated when compressed as a mixture; and that compression can reduce the long-term signal-to-noise ratio in certain conditions. These theoretical results are supported by software experiments using recorded speech signals.
Robust long-range source localization in the deep ocean using phase-only matched autoproduct processing
Authors: Geroski David J. , Dowling David R.
Published: July 2021

Passive source localization in the deep ocean using array signal processing techniques is possible using an algorithm similar to matched field processing (MFP) that interrogates a measured frequency-difference autoproduct instead of a measured pressure field [Geroski and Dowling, J. Acoust. Soc. Am. 146, 4727–4739 (2019)]. These results are extended herein to a new MFP-style algorithm, phase-only matched autoproduct processing, that is more robust at source-array ranges as large as 225 km. This new algorithm is herein described and compared to three existing approaches. The performance of all four techniques is evaluated using measured ocean propagation data from the PhilSea10 experiment. These data nominally span a 12-month period; include six source-array ranges from 129 to 450 km; and involve signals with center frequencies between 172.5 and 275 Hz, and bandwidths of 60 to 100 Hz. In all cases, weight vectors are calculated assuming a range-independent environment using a single sound-speed profile measured near the receiving array. The frequency-differencing techniques considered here are capable of localizing all six sources, with varying levels of consistency, using single-digit-Hz difference frequencies. At source-array ranges up to and including 225 km, the new algorithm requires fewer signal samples for success and is more robust to the choice of difference frequencies.
Does the Time-of-Day of Exercise Influence the Total Volume of Exercise? A Cross-Sectional Analysis of Objectively Monitored Physical Activity Among Active Individuals
Authors: Brooker Paige G. , Jung Mary E. , Kelly-Bowers Dominic , Morlotti Veronica , Gomersall Sjaan R. , King Neil A. , Leveritt Michael D.
Published: July 2021

Background: To improve compliance and adherence to exercise, the concept of temporal consistency has been proposed. Before- and after-work are periods when most working adults may reasonably incorporate exercise into their schedule. However, it is unknown if there is an association between the time-of-day that exercise is performed and overall physical activity levels. Methods: Activity was assessed over 1 week in a sample of 69 active adults (n = 41 females; mean age = 34.9 [12.3] y). At the end of the study, participants completed an interviewer-assisted questionnaire detailing their motivation to exercise and their exercise time-of-day preferences. Results: Participants were classified as “temporally consistent” (n = 37) or “temporally inconsistent” (n = 32) exercisers based on their accelerometry data. The “temporally consistent” group was further analyzed to compare exercise volume between “morning-exercisers” (n = 16) and “evening-exercisers” (n = 21). “Morning-exercisers” performed a greater volume of exercise than “evening-exercisers” (419 [178] vs 330 [233] min by self-report; 368 [224] vs 325 [156] min actigraph-derived moderate to vigorous physical activity, respectively). Conclusions: Our findings suggest that active individuals use a mixture of temporal patterns to meet PA guidelines. Time-of-day of exercise should be reported in intervention studies so the relationship between exercise time-of-day, exercise behavior, and associated outcomes can be better understood.
Tumbling and anomalous alignment of optically levitated anisotropic microparticles in chiral hollow-core photonic crystal fiber
Authors: Xie Shangran , Sharma Abhinav , Romodina Maria , Joly Nicolas Y. , Russell Philip St. J.
Published: July 2021

Tumbling motion of levitated anisotropic vaterite particle in chiral hollow core fiber results in anomalous optical alignment.
Mechanical forces regulate endothelial-to-mesenchymal transition and atherosclerosis via an Alk5-Shc mechanotransduction pathway
Authors: Mehta Vedanta , Pang Kar-Lai , Givens Christopher S. , Chen Zhongming , Huang Jianhua , Sweet Daniel T. , Jo Hanjoong , Reader John S. , Tzima Ellie
Published: July 2021

Mechanical forces regulate endothelial-to-mesenchymal transition via Alk5-Shc pathway.
Atomic mapping of periodic dipole waves in ferroelectric oxide
Authors: Gong Feng-Hui , Tang Yun-Long , Zhu Yin-Lian , Zhang Heng , Wang Yu-Jia , Chen Yu-Ting , Feng Yan-Peng , Zou Min-Jie , Wu Bo , Geng Wan-Rong , Cao Yi , Ma Xiu-Liang
Published: July 2021

Periodic arrays of electric dipole waves in ferroelectric oxides can be stabilized at room temperature by quenching.
Instant, multiscale dry transfer printing by atomic diffusion control at heterogeneous interfaces
Authors: Heo Seungkyoung , Ha Jeongdae , Son Sook Jin , Choi In Sun , Lee Hyeokjun , Oh Saehyuck , Jekal Janghwan , Kang Min Hyung , Lee Gil Ju , Jung Han Hee , Yea Junwoo , Lee Taeyoon , Lee Youngjeon , Choi Ji-Woong , Xu Sheng , Choi Joon Ho , Jeong Jae-Woong , Song Young Min , Rah Jong-Cheol , Keum Hohyun , Jang Kyung-In
Published: July 2021

Dry transfer printing by using atomic diffusion control enables multiscale and deterministic assembly of electronic devices.
The life span of fault-crossing channels
Authors: Dascher-Cousineau Kelian , Finnegan Noah J. , Brodsky Emily E.
Published: July 2021

The limits of channel offset

The offset of stream channels across a strike-slip fault offer a record of long-term slip rates. The process itself is an interesting case of landscape evolution because the streams will spill straight across the fault at some point and reset the offset. Dascher-Cousineau
et al.
developed a model for this process that they validated using observations from the Carrizo Plain in California. The model leverages transitions from active to abandoned stream channels to determine when and how drainage networks in these regions reorganize and allow quantification of both slip and bedload transport.

Science
, abf2320, this issue p.
204
Stable and selective catalysts for propane dehydrogenation operating at thermodynamic limit
Authors: Motagamwala Ali Hussain , Almallahi Rawan , Wortman James , Igenegbai Valentina Omoze , Linic Suljo
Published: July 2021

Hitting the limits on propene synthesis

The greater abundance of propane from shale gas has spurred efforts to use it as a propylene feedstock. Direct dehydrogenation catalysts consisting of platinum–tin alloy nanoparticles supported on alumina often must run with hydrogen dilution to avoid carbon buildup and excess tin to avoid alloy segregation. Motagamwala
et al.
report that platinum–tin nanoparticles interact more weakly with a silica support and the metals thus do not segregate. The use of undiluted reactants allowed the reaction to run near the thermodynamically limit of about 67% conversion with a selectivity to propylene of more than 99%. This catalyst also does not build up carbon and could run up to 30 hours without deactivation.

Science
, abg7894, this issue p.
217
Flyby reaction trajectories: Chemical dynamics under extrinsic force
Authors: Liu Yun , Holm Soren , Meisner Jan , Jia Yuan , Wu Qiong , Woods Toby J. , Martinez Todd J. , Moore Jeffrey S.
Published: July 2021

Shear selectivity

Chemical reactions typically proceed by distributing energy statistically among all accessible molecular vibrations. Liu
et al.
report that external shear forces can sometimes pry open strained carbon rings without dissipating energy into adjacent bond rotations. Through careful design and synthesis of polymer-embedded cyclobutyl rings, the authors showed that certain relative substituent geometries are preserved when sonication induces ring opening. Accompanying simulations support the instigation of “flyby” trajectories that channel energy narrowly to cleave the cyclic sigma bonds and then rapidly form acyclic pi bonds.

Science
, abi7609, this issue p.
208
Stepping out of the comfort zone
After Cooling: On Freon, Global Warming, and the Terrible Cost of Comfort
Eric Dean Wilson
Simon and Schuster, 2021. 480 pp.
Authors: Dreyfus Gabrielle
Published: July 2021

A writer grapples with the environmental and social costs of mechanical cooling
Sowing the seeds of leukemia before birth
Authors: Roberts Irene , Vyas Paresh
Published: July 2021

Distinct cooperation between a mutated gene and trisomy 21 triggers leukemia in utero
A shift in taste
Authors: Barker F. Keith
Published: July 2021

The evolution of sugar perception in songbirds began with a savory receptor
Removal of a migrated dexamethasone implant (Ozurdex) from the anterior chamber using an intravenous cannula
Authors: Ku Jae Yee , Mercieca Karl , Yau Kenneth
Published: July 2021

Ozurdex is a dexamethasone intravitreal implant used for the treatment of macular oedema. A rare but serious complication is the migration of the implant into the anterior chamber (AC) in eyes with absent or incomplete posterior capsules that may lead to corneal decompensation. We report the case of a 75-year-old woman who presented with a 1-day history of decreased vision in her left eye. She had a history of complicated cataract surgery and had received multiple Ozurdex implants for postoperative cystoid macular oedema in the same eye. She had significant left corneal decompensation and a mobile Ozurdex implant in the AC. We report a simple but novel surgical technique for removing an Ozurdex implant from the AC using an intravenous cannula (Venflon). This technique can also be applied to removing a fluocinolone acetonide (Iluvien) implant in similar situations.
Atypical presentation at acute gastritis: significant gastric wall thickening as a presentation of a primaryHelicobacter pyloriinfection in children
Authors: Nakamura Kiyokuni , Tamura Ryo , Yasui Yoshitomi , Okajima Hideaki
Published: July 2021

Helicobacter pyloriinfection could cause chronic inflammation in the stomach and induce peptic ulcer disease or even malignant tumour. The initial infection of the organism happens in childhood but most of cases are latent. We had a case of 10-year-old girl who presented with acute epigastric pain and significant thickening of the stomach wall on CT. The finding seemed atypical for acute gastritis so oesophagogastroduodenoscopy and serology examination were added and the primary infection ofH. pyloriwas confirmed with the exclusion of other possible diagnoses like eosinophilic gastritis and IgA vasculitis. Acute gastritis is one of the most common sickness in children, however, it would be worthwhile considering further investigation includingH. pyloriinfection in a case of atypical presentation to prevent negative consequences derived from chronicH. pyloriinfection.
14-Deoxy-11,12-Didehydroandrographolide Ameliorates Glucose Intolerance Enhancing the LKB1/AMPKα/TBC1D1/GLUT4 Signaling Pathway and Inducing GLUT4 Expression in Myotubes and Skeletal Muscle of Obese Mice
Authors: Chen Chih-Chieh , Lii Chong-Kuei , Lo Chia-Wen , Lin Yi-Hsueh , Yang Ya-Chen , Huang Chin-Shiu , Chen Haw-Wen
Published: July 2021

14-Deoxy-11,12-didehydroandrographolide (deAND), a bioactive component of Andrographis paniculata, has antidiabetic activity. AMP-activated protein kinase (AMPK) regulates glucose transport and ameliorates insulin resistance. The aim of the present study was to investigate whether activation of AMPK is involved in the mechanism by which deAND ameliorates insulin resistance in muscles. deAND amounts up to 40 [Formula: see text]M dose-dependently activated phosphorylation of AMPK[Formula: see text] and TBC1D1 in C2C12 myotubes. In addition, deAND significantly activated phosphorylation of LKB1 at 6 h after treatment, and this activation was maintained up to 48 h. deAND increased glucose uptake at 18 h after treatment, and this increase was time dependent up to 72 h. Compound C, an inhibitor of AMPK, suppressed deAND-induced phosphorylation of AMPK[Formula: see text] and TBC1D1 and reversed the effect on glucose uptake. In addition, the expression of GLUT4 mRNA and protein in C2C12 myotubes was up-regulated by deAND in a time-dependent manner. Promotion of GLUT4 gene transcription was verified by a pGL3-GLUT4 (837 bp) reporter assay. deAND also increased the nuclear translocation of MEF-2A and PPAR[Formula: see text]. After 16 weeks of feeding, the high-fat diet (HFD) inhibited phosphorylation of AMPK[Formula: see text] and TBC1D1 in skeletal muscle of obese C57BL/6JNarl mice, and deactivation of AMPK[Formula: see text] and TBC1D1 by the HFD was abolished by deAND supplementation. Supplementation with deAND significantly promoted membrane translocation of GLUT4 compared with the HFD group. Supplementation also significantly increased GLUT4 mRNA and protein expression in skeletal muscle compared with the HFD group. The hypoglycemic effects of deAND are likely associated with activation of the LKB1/AMPK[Formula: see text]/TBC1D1/GLUT4 signaling pathway and stimulation of MEF-2A- and PPAR[Formula: see text]-dependent GLUT4 gene expression, which account for the glucose uptake into skeletal muscle and lower blood glucose levels.
On Statistical Deferred A-Convergence of Uncertain Sequences
Authors: Baliarsingh P.
Published: July 2021

In this paper, as a part of uncertain theory, we discuss various concepts of convergence and statistical convergence of complex uncertain sequences. Using uncertain variables, the convergence of uncertain sequences of complex numbers such as the idea of convergence in measure, convergence in mean, convergence in distribution and convergence uniformly almost surely via deferred Cesàro mean and a regular matrix A are introduced. Also, some relations among these convergence are established. Certain results on deferred statistical convergence of order α, (0 < α ≤ 1) for complex uncertain sequences are studied in detail.
Clustering Techniques to Improve Scalability and Accuracy of Recommender Systems
Authors: Das Joydeep , Majumder Subhashis , Mali Kalyani
Published: July 2021

Recommender systems have emerged as a class of essential tools in the success of modern e-commerce applications. These applications typically handle large datasets and often face challenges like data sparsity and scalability. Clustering techniques help to reduce the computational time needed for recommendation as well as handle the sparsity problem more efficiently. Traditional clustering based recommender systems create partitions (clusters) of the user-item rating matrix and execute the recommendation algorithm in the clusters separately in order to decrease the overall runtime of the system. Each user or item generally belong to at most one cluster. However, it may so happen that some users (boundary users) present in a particular cluster exhibit higher similarity with the preferences of the users residing in the nearby clusters than the ones present in their own cluster. Therefore, we propose a clustering based scalable recommendation algorithm that has a provision for switching a user from its original cluster to another cluster in order to provide more accurate recommendations. For a user belonging to multiple clusters, we aggregate recommendations from those clusters to which the user belongs in order to produce the final set of recommendations to that user. In this work, we propose two types of clustering, one on the basis of rating and the other on the basis of frequency and then compare their performances. Finally, we explore the applicability of cluster ensembles techniques in the proposed method. Our aim is to develop a recommendation framework that can scale well to handle large datasets without much affecting the recommendation quality. The outcomes of our experiments clearly demonstrate the scalability as well as efficacy of our method. It reduces the runtime of the baseline CF algorithm by a minimum of 58% and a maximum of 90% for MovieLens-10M dataset, and a minimum of 42% and a maximum of 84% for MovieLens-20M dataset. The accuracies of recommendations in terms of F1, MAP and NDCG metrics are also better than the existing clustering based recommender systems.
Wavelet estimation for factor models with time-varying loadings
Authors: Cataño Duván Humberto , Rodríguez-Caballero C. Vladimir , Peña Daniel , Chiann Chang
Published: July 2021

We introduce a high-dimensional factor model with time-varying loadings. We cover both stationary and nonstationary factors to increase the possibilities of applications. We propose an estimation procedure based on two stages. First, we estimate common factors by principal components. In the second step, considering the estimated factors as observed, the time-varying loadings are estimated by an iterative generalized least squares procedure using wavelet functions. We investigate the finite sample features by some Monte Carlo simulations. Finally, we apply the model to study the Nord Pool power market’s electricity prices and loads.
Yenisei–Khatanga Composite Tectono-Sedimentary Element, northern east Siberia
Authors: Deev E. V. , Shemin G. G. , Vernikovsky V. A. , Bostrikov O. I. , Glazyrin P. A. , Matushkin N. Y.
Published: July 2021

The Yenisei–Khatanga Composite Tectono-Sedimentary Element (CTSE) is located between the Siberian Craton and the Taimyr–Severnaya Zemlya Fold and Thrust Belt. The total thickness of the Mesoproterozoic–Cenozoic sediments of the Yenisei–Khatanga CTSE reaches 20–25 km, and they are divided into four tectono-sedimentary elements (TSEs): (i) Mesoproterozoic–early Carboniferous Siberian Craton continental margin; (ii) middle Carboniferous–Permian synorogenic Taimyr foreland basin; (iii) late Permian–Early Triassic synrift; and (iv) Triassic–Early Paleocene post-rift. The last one is the most important in terms of its petroleum potential and is the most drilled part of the CTSE. Its thickness accounts for half of the total thickness of the Yenisei–Khatanga CTSE. The margins of the post-rift TSE and the inner system of inversion swells and adjacent troughs and depressions were shaped by three tectonic events: (i) Middle Triassic uplift of South Taimyr; (ii) the Late Jurassic–Early Cretaceous Verkhoyansk Orogeny; and (iii) Late Cenozoic uplift. These processes led to more intense migration of hydrocarbons, the trap formation and their infill with hydrocarbons. Triassic, Jurassic and Lower Cretaceous source rocks are mostly gas-prone; and of the 20 discovered fields in Jurassic and Cretaceous plays, 17 are gas or mixed-type fields.
Reconstruction of the 2002 tsunami at Stromboli using the non-hydrostatic WAVE model (NHWAVE)
Authors: Fornaciai Alessandro , Favalli Massimiliano , Nannipieri Luca
Published: July 2021

In December 2002, two landslides along the Sciara del Fuoco at Stromboli triggered large tsunami waves that caused significant damage on the coast of the island up to an elevation of about 10 m above sea-level. In this work, we report in detail the items and the methods used to reconstruct the 2002 tsunami at Stromboli highlighting their strengths and limits. In particular, we describe: (1) the non-hydrostatic WAVE model used to simulate the triggering landslide, the wave propagation and the inundation/runup on the land; (2) the data and methods used to generate the topo-bathymetric computational grid; and (3) the field data acquired on Stromboli after the 2002 tsunami used as ground truth for checking the simulation outputs. Our results show that the most severe damage on the coast of Stromboli could have been caused by the interaction of successive waves triggered by the same landslide. In addition, we also describe the influence that the bathymetry had on the waves propagation and interaction.
ELRUNA
Authors: Qiu Zirou , Shaydulin Ruslan , Liu Xiaoyuan , Alexeev Yuri , Henry Christopher S. , Safro Ilya
Published: July 2021

Networks model a variety of complex phenomena across different domains. In many applications, one of the most essential tasks is to align two or more networks to infer the similarities between cross-network vertices and to discover potential node-level correspondence. In this article, we propose ELRUNA (
el
imination
ru
le-based
n
etwork
a
lignment), a novel network alignment algorithm that relies exclusively on the underlying graph structure. Under the guidance of the elimination rules that we defined, ELRUNA computes the similarity between a pair of cross-network vertices iteratively by accumulating the similarities between their selected neighbors. The resulting cross-network similarity matrix is then used to infer a permutation matrix that encodes the final alignment of cross-network vertices. In addition to the novel alignment algorithm, we improve the performance of
local search
, a commonly used postprocessing step for solving the network alignment problem, by introducing a novel selection method RAWSEM (
ra
ndom-
w
alk-based
se
lection
m
ethod) based on the propagation of vertices’ mismatching across the networks. The key idea is to pass on the initial levels of mismatching of vertices throughout the entire network in a random-walk fashion. Through extensive numerical experiments on real networks, we demonstrate that ELRUNA significantly outperforms the state-of-the-art alignment methods in terms of alignment accuracy under lower or comparable running time. Moreover, ELRUNA is robust to network perturbations such that it can maintain a close-to-optimal objective value under a high level of noise added to the original networks. Finally, the proposed RAWSEM can further improve the alignment quality with a smaller number of iterations compared with the naive local search method.

Reproducibility
: The source code and data are available at https://tinyurl.com/uwn35an.
A Composable Monitoring System for Heterogeneous Embedded Platforms
Authors: Valente Giacomo , Fanni Tiziana , Sau Carlo , Mascio Tania Di , Pomante Luigi , Palumbo Francesca
Published: July 2021

Advanced computations on embedded devices are nowadays a must in any application field. Often, to cope with such a need, embedded systems designers leverage on complex heterogeneous reconfigurable platforms that offer high performance, thanks to the possibility of specializing/customizing some computing elements on board, and are usually flexible enough to be optimized at runtime. In this context, monitoring the system has gained increasing interest. Ideally, monitoring systems should be non-intrusive, serve several purposes, and provide aggregated information about the behavior of the different system components. However, current literature is not close to such ideality: For example, existing monitoring systems lack in being applicable to modern heterogeneous platforms. This work presents a hardware monitoring system that is intended to be minimally invasive on system performance and resources, composable, and capable of providing to the user homogeneous observability and transparent access to the different components of a heterogeneous computing platform, so system metrics can be easily computed from the aggregation of the collected information. Building on a previous work, this article is primarily focused on the extension of an existing hardware monitoring system to cover also specialized coprocessing units, and the assessment is done on a Xilinx FPGA-based System on Programmable Chip. Different explorations are presented to explain the level of customizability of the proposed hardware monitoring system, the tradeoffs available to the user, and the benefits with respect to standard de facto monitoring support made available by the targeted FPGA vendor.
Extending C++ for Heterogeneous Quantum-Classical Computing
Authors: Mccaskey Alexander , Nguyen Thien , Santana Anthony , Claudino Daniel , Kharazi Tyler , Finkel Hal
Published: July 2021

We present qcor—a language extension to C++ and compiler implementation that enables heterogeneous quantum-classical programming, compilation, and execution in a single-source context. Our work provides a first-of-its-kind C++ compiler enabling high-level quantum kernel (function) expression in a quantum-language agnostic manner, as well as a hardware-agnostic, retargetable compiler workflow targeting a number of physical and virtual quantum computing backends. qcor leverages novel Clang plugin interfaces and builds upon the XACC system-level quantum programming framework to provide a state-of-the-art integration mechanism for quantum-classical compilation that leverages the best from the community at-large. qcor translates quantum kernels ultimately to the XACC intermediate representation, and provides user-extensible hooks for quantum compilation routines like circuit optimization, analysis, and placement. This work details the overall architecture and compiler workflow for qcor, and provides a number of illuminating programming examples demonstrating its utility for near-term variational tasks, quantum algorithm expression, and feed-forward error correction schemes.