bluuebunny/crossref_metadata_2025 huggingface dataset:
Learning from organisational changes in the management of breast cancer patients during the COVID‐19 pandemic: Preparing for a second wave at a breast unit in northern Italy
Authors: Ferro Antonella , Cristofolini Paolo , Garcia‐Etienne Carlos A. , Caffo Orazio , Pellegrini Marco , Fantò Carmine , Mussari Salvatore , Campregher Monica , Lazzeri Silvia , Cantarelli Sara , Guarrera Giovanni Maria
Published: April 2021

Italy was the first western country to be hit by the initial wave of severe adult respiratory syndrome coronavirus 2 pandemic, which has been more widespread in the country's northern regions. Early reports showing that cancer patients are more susceptible to the infection posed a particular challenge that has guided our Breast Unit at Hub Hospital in Trento to making a number of stepwise operational changes. New internal guidelines and treatment selection criteria were drawn up by a virtual multidisciplinary tumour board that took into account the risks and benefits of treatment, and distinguished the patients requiring immediate treatment from those whose treatment could be delayed. A second wave of the pandemic is expected in the autumn as gatherings in closed places increase. We will take advantage of the gained experience and organisational changes implemented during the first wave in order to improve further, and continue to offer breast cancer management and treatment to our vulnerable patient population.
Small‐scale–irrigated agriculture empowered women‐headed households in Tigray, Ethiopia*
Authors: Smur Gebrehiwet , Teka Kassa , Teklehaimanot Abadi
Published: April 2021

Agricultural production in Ethiopia is primarily rainfed, which is characterized by its erratic and often inadequate nature. Women‐headed households are more susceptible to the resulting poor agricultural production. Hence, small‐scale irrigation has been considered as a solution in the country. However, research on its social and economic contribution for these households is limited. Thus, this study aimed at closing this research gap taking Kilte‐Awulaelo District as a case study. The study covered a total of 205 respondents (187 individuals and one group discussion with 18 participants) from three villages. Data were obtained using semi‐structured questionnaires taking changes in household income, housing improvement, resource control, access to social services, and level of community participation as major indicators. The survey indicated that there was an improvement in women‐headed households' overall social and economic benefits after introducing small‐scale irrigation. Small‐scale irrigation significantly increased women‐headed households' income from livestock and crop production by 24.3% and 68.8%, respectively. This led women‐headed households to have access to control of household resources, financial independency, profit, employment opportunities, psychological well‐being, and community participation. It can be concluded that small‐scale irrigation agriculture played a significant role in empowering women‐headed households.
Migration in China: To work or to wed?
Authors: Dupuy Arnaud
Published: April 2021

This paper develops a model encompassing both matching and hedonic models, studies its properties, and provides identification and estimation strategies. We bring the model to data on internal migration in China to answer the question raised in the title. We estimate the migration surplus of singles and couples and the marital surplus of natives and, using counterfactuals together with our identification strategy, quantify the “marrying‐up” and the “work” effects of migration. Results show that, for floating (resp. permanent) migrant women married with urban men, the “marrying‐up” effect is positive but 3.5 (resp. 5) times smaller than the “work” effect. However, as these migrant women enter the urban marriage market, they generate equilibrium “marrying‐up” effects for all men and women by changing the relative supply of women on both the rural and urban marriage markets. These effects can be large relative to the “work” effect of migration for some types of migrants (floating migrant women married with a permanent migrant man and floating migrant women married with a floating migrant man) and represent about 13% of the equilibrium utility of urban native men.
Polymeric metal‐containing ionic liquid sorbent coating for the determination of amines using headspace solid‐phase microextraction
Authors: Yavir Kateryna , Eor Philip , Kloskowski Adam , Anderson Jared L.
Published: April 2021

This study describes the design, synthesis, and application of polymeric ionic liquid sorbent coatings featuring nickel metal centers for the determination of volatile and semivolatile amines from water samples using headspace solid‐phase microextraction. The examined polymeric ionic liquid (PIL) sorbent coatings were composed of two ionic liquid monomers (tetra(3‐vinylimidazolium)nickel bis[(trifluoromethyl)sulfonyl]imide [Ni2+(VIM)4] 2[NTf2–] and 1‐vinyl‐3‐hexylimidazolium [HVIM+][NTf2–]), and an ionic liquid cross‐linker (1,12‐di(3‐vinylimidazolium)dodecane  [(VIM)2C122+] 2[NTf2–]). With these ionic liquid monomers and cross‐linkers, three different types of coatings were prepared: PIL 1 based on the neat [Ni2+(VIM)4] 2[NTf2–] monomer, PIL 2 consisting of the [Ni2+(VIM)4] 2[NTf2–] monomer with addition of cross‐linker, and PIL 3 composed of the [HVIM+][NTf2–] monomer and cross‐linker. Analytical performance of the prepared sorbent coatings using headspace solid‐phase microextraction gas chromatography–mass spectrometry was compared with the polydimethylsiloxane and polyacrylate commercial coatings. The PIL 2 sorbent coating yielded the highest enrichment factors ranging from 5500 to over 160 000 for the target analytes. The developed headspace solid‐phase microextraction gas chromatography–mass spectrometry method was applied for the analysis of real samples (the concentration of amines was 200 μg/L), producing relative recovery values in the range of 90.9–120.0% (PIL 1) and 83.0–122.7% (PIL 2) from tap water, and 84.8–112.4% (PIL 1) and 79.2–119.3% (PIL 2) from lake water.
Knowledge creation through collective phronesis
Authors: Kodama Mitsuru
Published: April 2021

An important proposition for corporate strategy aiming to adapt to or to create the convergence world view, is the creation of boundaries knowledge and convergence knowledge by the practical knowledge (practical wisdom) of practitioners. This paper presents elements of the collective phronesis of practitioners for the creation of boundaries knowledge and convergence knowledge, the basis for innovation through convergence. Collective phronesis, which is aggregations of leading autonomous and decentralized phronesis, entails the use of boundaries vision to inspire and create boundaries knowledge and Ba synthesizing capabilities to dynamically form the multilayered networks of Ba required for the creation of convergence knowledge. From in‐depth case studies of the high‐tech companies Apple and NTT DOCOMO, this paper presents the knowledge creating company model for continuously bringing about boundaries knowledge and convergence knowledge. As sustainable innovation communities, knowledge creating companies drive collective phronesis to combine various contradictions both inside and outside of themselves, including with customers, through their Ba synthesizing capabilities to dynamically configure and reconfigure multi‐layered networks of various Ba to achieve boundaries innovation.
Strong and regionally distinct links between ice‐retreat timing and phytoplankton production in the Arctic Ocean
Authors: Song Hongjun , Ji Rubao , Jin Meibing , Li Yun , Feng Zhixuan , Varpe Øystein , Davis Cabell S.
Published: April 2021

Recent rapid sea‐ice changes in the Arctic Ocean have been widely considered to alter phytoplankton bloom timing and primary production, but the magnitude and regionality of this effect remain unclear. Here, we examined the spatial patterns in bloom timing, bloom magnitude, and primary productivity in relation to ice‐retreat timing, using a combination of satellite observations and numerical modeling. We found distinct regional differences in how the phytoplankton bloom relates to ice‐retreat timing. In the Arctic shelf regions, earlier and stronger blooms follow earlier annual ice retreats and enhanced light availability. By contrast, in some parts of the central Arctic, especially in the Canada Basin, there have been weakened blooms and reduced primary production in recent years. This reduction is largely due to a chain reaction triggered by earlier ice‐melt and enhanced haline stratification, which further suppress vertical nutrient exchange and reduce surface nutrients in an already nutrient‐limited system. Recognizing and quantifying strong and regionally distinct links between sea‐ice retreat and primary production will improve spatiotemporal projections of biogeochemical cycles and trophic flows in Arctic marine ecosystems.
CMS reverses course, rescinds Texas waiver approval
Authors: Enos Gary
Published: April 2021

Saying her agency had erred in allowing Texas to be fast‐tracked for a long‐term extension of its Section 1115 Medicaid waiver, the acting administrator of the Centers for Medicare & Medicaid Services (CMS) this month rescinded a waiver approval that had been granted by the Trump administration.
Discovery of a Novel Antimicrobial Agent by the Virtual Screening of a Library of Small Molecules
Authors: Dighe Satish N. , van Akker Suzannah R. , Mathew Marina , Perera Madusha , Collet Trudi A.
Published: April 2021

A virtual screening approach based upon a combination of docking and pharmacophore methods was utilized on a library of 1.4 million molecules to identify novel antimicrobial agents, which may potentially act via inhibition of the caseinolytic protease. Using this method, compound 6 was found to be bactericidal against three staphylococcal species (minimum inhibitory concentration (MIC)=4–16 μg/mL). Further, subsequent structural optimization of 6 led to the identification of compound 24, which was shown to be the most potent analog within the series (MIC=4 μg/mL) and outperforming the antibiotic controls for two of the staphylococcal species. The newly discovered antimicrobial agent (24) demonstrated excellent in silico ADME properties and was non‐toxic when tested on two human skin cell lines. As such, compound 24 has the potential for use as a lead molecule in the development of a novel class of antimicrobial agents.
On the solutions for generalised multiorder fractional partial differential equations arising in physics
Authors: Purohit Sunil Dutt , Baleanu Dumitru , Jangid Kamlesh
Published: April 2021

In this article, we have studied solutions of a generalised multiorder fractional partial differential equations involving the Caputo time‐fractional derivative and the Riemann–Liouville space fractional derivatives using Laplace–Fourier transform technique. Proposed generalised multiorder fractional partial differential equation is reducible to Schrödinger equation, wave equation and diffusion equation in a more general sense, and hence, solutions of these equations are specifically noted. Not only this, solutions of equation proposed in the stochastic resetting theory in the context of Brownian motion can also be found in a general regime.
Implementing newborn screening for sickle cell disease in Korle Bu Teaching Hospital, Accra: Results and lessons learned
Authors: Segbefia Catherine I. , Goka Bamenla , Welbeck Jennifer , Amegan‐Aho Kokou , Dwuma‐Badu Diana , Rao Sudha , Salifu Nihad , Oppong Samuel A. , Odei Eric , Ohene‐Frempong Kwaku , Odame Isaac
Published: April 2021

Background

Early diagnosis of sickle cell disease (SCD) through newborn screening (NBS) is a cost‐effective intervention, which reduces morbidity and mortality. In sub‐Saharan Africa (SSA) where disease burden is greatest, there are no universal NBS programs and few institutions have the capacity to conduct NBS. We determined the feasibility and challenges of implementing NBS for SCD in Ghana's largest public hospital.

Procedure

The SCD NBS program at Korle Bu Teaching Hospital (KBTH) is a multiyear partnership between the hospital and the SickKids Center for Global Child Health, Toronto, being implemented in phases. The 13‐month demonstration phase (June 2017–July 2018) and phase one (November 2018–December 2019) focused on staff training and the feasibility of universal screening of babies born in KBTH.

Results

During the demonstration phase, 115 public health nurses and midwives acquired competency in heel stick for dried blood spot sampling. Out of 9990 newborns, 4427 babies (44.3%) were screened, of which 79 (1.8%) were identified with presumptive SCD (P‐SCD). Major challenges identified included inadequate nursing staff to perform screening, shortage of screening supplies, and delays in receiving screening results. Strategies to overcome some of the challenges were incorporated into phase one, resulting in increased screening coverage to 83.7%.

Conclusions

Implementing NBS for SCD in KBTH presented challenges with implications on achieving and sustaining universal NBS in KBTH and other settings in SSA. Specific steps addressing these challenges comprehensively will help build on the modest initial gains, moving closer toward a sustainable national NBS program.
Fetally‐injected drugs for immobilization and analgesia do not modify fetal brain development in a rabbit model
Authors: van der Veeken Lennart , Inversetti Annalisa , Galgano Angela , Bleeser Tom , Papastefanou Ioannis , van de Merwe Johannes , Rex Steffen , Deprest Jan
Published: April 2021

Objective

During fetal surgery, fetuses receive medication (atropine‐fentanyl‐curare) to prevent fetal pain, movement and bradycardia. Although essential there has been no detailed review of potential side effects. Herein we aimed to assess the effects of this medication cocktail on fetal brain development in a rabbit model.

Methods

Pregnant does underwent laparotomy at 28 days of gestation. Two pups of each horn were randomized to an ultrasound guided injection with medication (atropine‐cisatracurium‐fentanyl, as clinically used) or saline (sham). The third pup was used as control. At term, does were delivered by cesarean. Outcome measures were neonatal biometry, neuromotoric functioning and neuro‐histology (neuron density, synaptic density and proliferation).

Results

Maternal vital parameters remained stable during surgery. Fetal heart rates did not differ before and after injection, and were comparable for the three groups. At birth, neonatal body weights and brain‐to‐body weight ratios were also comparable. Both motor and sensory neurobehavioral scores were comparable. There were no differences in neuron density or proliferation. Sham pups, had a lower synaptic density in the hippocampus as compared to the medication group, however there was no difference in the other brain areas.

Conclusion

In the rabbit model, fetal medication does not appear to lead to short‐term neurocognitive effects.
Structural dynamics of the complex of calmodulin with a minimal functional construct of eukaryotic elongation factor 2 kinase and the role of Thr348 autophosphorylation
Authors: Piserchio Andrea , Long Kimberly , Lee Kwangwoon , Kumar Eric A. , Abzalimov Rinat , Dalby Kevin N. , Ghose Ranajeet
Published: April 2021

The calmodulin (CaM) activated α‐kinase, eukaryotic elongation factor 2 kinase (eEF‐2K), plays a central role in regulating translational elongation by phosphorylating eukaryotic elongation factor 2 (eEF‐2), thereby reducing its ability to associate with the ribosome and suppressing global protein synthesis. Using TR (for truncated), a minimal functional construct of eEF‐2K, and utilizing hydrogen/deuterium exchange mass spectrometry (HXMS), solution‐state nuclear magnetic resonance (NMR) and biochemical approaches, we investigate the conformational changes accompanying complex formation between Ca2+‐CaM and TR and the effects of autophosphorylation of the latter at Thr348, its primary regulatory site. Our results suggest that a CaM C‐lobe surface, complementary to the one involved in recognizing the calmodulin‐binding domain (CBD) of TR, provides a secondary TR‐interaction platform. CaM helix F, which is part of this secondary surface, responds to both Thr348 phosphorylation and pH changes, indicating its integration into an allosteric network that encompasses both components of the Ca2+‐CaM•TR complex. Solution NMR data suggest that CaMH107K, which carries a helix F mutation, is compromised in its ability to drive the conformational changes in TR necessary to enable efficient Thr348 phosphorylation. Biochemical studies confirm the diminished capacity of CaMH107K to induce TR autophosphorylation compared to wild‐type CaM.
Two new invasive Ips bark beetles (Coleoptera: Curculionidae) in mainland China and their potential distribution in Asia
Authors: Li You , Johnson Andrew J , Gao Lei , Wu Chengxu , Hulcr Jiri
Published: April 2021

Background

Ips is a bark beetle genus of 45 species, many of which are pests of conifer forests and plantations under stress. Twelve Ips species are recorded from China and presumably native there. From 2016 to 2018, specimens suspected to be Ips calligraphus and Ips grandicollis, were collected from traps with ethanol as a sole lure in Zhuhai, Guangdong, China. Both species originate in North America and infest various species of native or introduced pines. Since Ips species are known to cause or exacerbate problems in pine plantations, and a regional survey using traps baited with attractants were implemented in this study to investigate the extent of the introduction.

Results

Both I. calligraphus and I. grandicollis have been collected repeatedly from several traps with Ips attractants in Zhuhai, Guangdong, China since 2016. Potential distributions of these two species in Asia, inferred using MaxEnt, is extensive, given the high projected environmental suitability in North America, South America, Mediterranean Europe, Northern Africa, and Eastern Asia. The host plant of I. calligraphus from Zhuhai was identified as slash pine Pinus elliottii using DNA barcoding of gut contents from trapped individuals.

Conclusion

This is the first report of the establishment of two American pine bark beetles, I. calligraphus and I. grandicollis in continental Asia. The gut content of both species suggests that these pest feeds on a non‐native host. Whether the two species present high‐risk to Asian forests will become clear with more research on their interactions with native pines.
Ferroelectric Aluminum Scandium Nitride Thin Film Bulk Acoustic Resonators with Polarization‐Dependent Operating States
Authors: Wang Jialin , Zheng Yue , Ansari Azadeh
Published: April 2021

Given the recent discovery of ferroelectricity in highly doped AlN films and their widespread use in bulk acoustic wave (BAW) filters, the ferroelectric and acoustic performance of AlScN‐based devices at two distinct polarization states, i.e., nitrogen (N)‐polar and metal‐polar states, is investigated. Unreleased metal−ferroelectric−metal (MFM) capacitors, as well as suspended MFM structures in the form of thin‐film bulk acoustic resonators (FBARs), are fabricated based on Mo/AlScN/Mo‐sputtered films with ≈30% Sc concentration. The hysteresis polarization−electric field (P−E) loops and internal resistance of the MFM capacitors are characterized. The FBAR devices are characterized at the two polarization states, where the polarization inversion is accompanied by the modulation of thin‐film stress and resistance. Furthermore, the as‐fabricated N‐polar FBAR shows a fundamental thickness‐mode resonance frequency of 3.17 GHz, with a quality factor (QBode) of 572 and a high effective electromechanical coupling coefficient (kt2) of 11.4%. The FBAR frequency response changes when the polarization is switched from N‐polar to metal‐polar. Herein, the first investigations of electric and acoustic properties of N‐polar and metal‐polar AlScN‐based devices are demonstrated, paving the way for the realization of high‐kt2‐reconfigurable acoustic filters for next‐generation communication systems operating at the super‐high‐frequency (SHF) range.
Zimbabwe's national museums and monuments: Constructing culture and making money
Authors: Zukas Lorna L.
Published: April 2021

This article analyzes national monuments, museums, and Cultural Heritage Sites in Zimbabwe for their symbolic and economic value as politicized and contested landscapes. It argues that museums and national legacy sites are developed as public places that camouflage but also reveal social memory in the process of state identity formation. Developments at cultural and heritage sites include a dual mandate to assert a new African national identity and attract tourism. I argue that the visual, cultural, and political narratives used to (re)inscribe a traditional African past on the landscape evoke conflicting emotional and intellectual responses among varied audiences. Monument planning and restoration of museums and Cultural Heritage Sites must balance the needs of multiple constituencies to avoid conflicts that can arise if development plans do not align with tourist desires or respect a community's use of a space or understanding of the past. Therefore, the ability of heritage and cultural sites to serve as engines of development for the tourist economy is questionable, but as public platforms for the expression of indigenous histories and cultures, they provide significant social and cultural value to local groups.
Rhenium Effect on the Performance of CoMoNi/γ‐Al2O3 Catalyst in Thiophene Hydrodesulphurization. Performance Evaluation and Process Kinetics
Authors: Doukeh Rami , Leostean Cristian , Bolocan Ion , Trifoi Ancuta Roxana , Banu Ionut
Published: April 2021

The rhenium effect on the performance of CoMoNi/γ‐Al2O3 catalyst was studied in thiophene hydrodesulphurization. The unsulfided and freshly sulfided catalysts were characterized by N2 adsorption‐desorption, IR spectroscopy, X‐ray photoelectron spectroscopy (XPS) and total acidity. The effects of reaction temperature, pressure, and liquid hourly space velocity (LHSV) on thiophene HDS performance shown that the activity of the CoMoNiRe/γ‐Al2O3 catalyst for thiophene HDS was superior to that of the CoMoNi/γ‐Al2O catalyst, which was mainly ascribed to the higher acidic functional groups. Based on Langmuir‐Hinshelwood approach, a kinetic model for thiophene HDS over both catalysts have been developed. In this respect, two mechanisms have been considered, one hypothesizing that hydrogen is adsorbed on different active centers than thiophene (two‐centers mechanism) and the other considering one type of active centers. Based on statistical reasons, the kinetic model considering two types of active centers proved to be more adequate in representing the experimental results.
Effects of Ni‐Loading on the Performance of Ni/SiO2 Catalysts for the Highly Selective Hydrogenation of Biphenyl to Cyclohexylbenzene
Authors: Li Wei , Zhao Zhipeng , Li Jianpeng , Liu Yuan , Gao Beibei , Li Xiaonan , Zhang Meng , Liu Zhongyi
Published: April 2021

This article investigated the effects of Ni loading on the performance of Ni/SiO2 catalysts for the selective hydrogenation of biphenyl (BP) to cyclohexylbenzene (CHB). The catalysts were characterized by the techniques of thermogravimetric analysis, X‐ray powder diffraction, N2‐physisorption, scanning electron microscope, inductively coupled plasma‐atomic emission spectroscopy, transmission electron microscope, H2 temperature‐programmed reduction. It was found that under the given reaction conditions, BP conversion showed an increased trend with the increasing Ni loading. However, 25 % Ni/SiO2 catalyst exhibited the lower CHB yield than 20 % Ni/SiO2 catalyst, which was attributed to the overhydrogenation of BP on the former with the excessive metal active sites. Besides, over 25 % Ni/SiO2 catalyst, BP conversion gradually increased with the extended reaction time, the enhanced hydrogen pressure or the improved temperature, but CHB selectivity and yield increased first and then decreased. Additionally, isopropanol was considered to be the best one among the representative solvents in BP hydrogenation reaction. Moreover, the conversion of BP and the selectivity/yield of CHB could keep above 99 % and 96 %, respectively, after eight consecutive cycles.
Ti3+ Tuning the Ratio of Cu+/Cu0 in the Ultrafine Cu Nanoparticles for Boosting the Hydrogenation Reaction
Authors: Zhang Ziyang , Wang Zhong‐Li , An Kang , Wang Jiaming , Zhang Siran , Song Pengfei , Bando Yoshio , Yamauchi Yusuke , Liu Yuan
Published: April 2021

Hydrogenation of diesters to diols is a vital process for chemical industry. The inexpensive Cu+/Cu0‐based catalysts are highly active for the hydrogenation of esters, however, how to efficiently tune the ratio of Cu+/Cu0 and stabilize the Cu+ is a great challenge. In this work, it is demonstrated that doped Ti ions can tune the ratio of Cu+/Cu0 and stabilize the Cu+ by the TiOCu bonds in Ti‐doped SiO2 supported Cu nanoparticle (Cu/Ti–SiO2) catalysts for the high conversion of dimethyl adipate to 1,6‐hexanediol. In the synthesis of the catalysts, the Ti4+OCu2+ bonds promote the reduction of Cu2+ to Cu+ by forming Ti3+OVCu+ (OV: oxygen vacancy) bonds and the amount of Ti doping can tune the ratio of Cu+/Cu0. In the catalytic reaction, the O vacancy activates CO in the ester by forming new Ti3+δORCu1+δ bonds (OR: reactant oxygen), and Cu0 activates hydrogen. After the products are desorbed, the Ti3+δORCu1+δ bonds return to the initial state of Ti3+OVCu+ bonds. The reversible TiOCu bonds greatly improve the activity and stability of the Cu/Ti–SiO2 catalysts. When the content of Ti is controlled at 0.4 wt%, the conversion and selectivity can reach 100% and 98.8%, respectively, and remain stable for 260 h without performance degradation.
Mechanism for Refining Grains and Effect of Microstructural Characteristics on Low‐Temperature Toughness for Industrial EH460 Heavy‐Gauge Steel
Authors: Wang Hongtao , Tian Yong , Ye Qibin , Kan Liye , Wang Zhaodong , Wang Guodong
Published: April 2021

The mechanism for refining grains in industrial EH460 heavy‐gauge steel with a thickness of 80 mm and above is investigated using electron backscattered diffraction. Charpy impact and drop‐weight tests are conducted to quantify the effect of microstructures and texture on low‐temperature toughness. Abundant ferrite grains that form and impinge from different prior‐austenite grains increase the high‐angle grain boundary (HAGB) fraction. The result is a refined effective grain size of 3.7 ± 4.2 μm, a high HAGB fraction of 62.1%, and an average Charpy impact absorbed energy of ≈209 J at −80 °C. The excellent impact toughness is due to the high intensity of texture with types of {113}−{112}<110> and {332}<113>, as well as the uniformly distributed {110} slip planes and {001} cleavage planes. The high intensities of {110}<111> and {110}<112> also improve the drop‐weight toughness. However, due to plastic constraint in the larger drop‐weight specimens, increased plane strain in the inner regions is the root cause of the brittle fracture of these specimens at −70 °C. Nevertheless, the improved drop‐weight performance is attributed to the plane stress deformation at the specimen edges and also the occurrence of delamination in the central section.
Developing deep learning in science classrooms: Tactics to manage epistemic uncertainty during whole‐class discussion
Authors: Chen Ying‐Chih , Techawitthayachinda Ratrapee
Published: April 2021

Science teachers usually view students' uncertainty as a barrier to overcome, a negative experience to be avoided, a deficiency in need of remedy. Building on the theory of deep learning in science as a generative and sensemaking process, the purpose of this design‐based study is to identify tactics for teachers to manage their students' epistemic uncertainty as a pedagogical resource to develop student conceptual understanding during whole‐class discussion. Classroom observations of whole‐class discussion were collected from six teachers' classes ranging from third to eighth grade. A total of 18 whole‐class discussions were collected, transcribed, and analyzed. A storyline talk to manage uncertainty during whole‐class discussion was developed and consisted of three stages: (1) Raise epistemic uncertainty through creating ambiguous conditions; (2) Maintain epistemic uncertainty through preventing immature disclosure and discussing alternative explanations or conflicting ideas; and (3) Reduce epistemic uncertainty through making coherent connections among current uncertainty, prior knowledge, and familiar phenomena. Seven nuanced tactics used by teachers to achieve each stage of uncertainty management were identified. The results suggest that managing uncertainty goes beyond asking questions and problematizing phenomena. When engaging students in storyline‐based whole‐class discussion, teachers should focus on one specific uncertainty and establish a coherent, consistent storyline that raises, maintains, and reduces student uncertainty to horizontally and vertically construct a collective knowledge among students. The horizontal nature occurs within a stage of management, and the vertical nature of a storyline talk is related to moving along from stage to stage. Through the storyline talk focusing on students' epistemic uncertainty, students can truly become agents in the learning process when the lesson is centered on and driven by students' uncertainty.
AgNO3⋅NH4NO3 – an enigmatic double‐salt type “decomposition intermediate” of diamminesilver(I) permanganate
Authors: Béres Kende Attila , Petruševski Vladimir , Holló Berta Barta , Németh Péter , Fogaça Lara , Paiva Franguelli Fernanda , Farkas Attila , Menyhárd Alfréd , Szilágyi Imre Miklós , Kótai László
Published: April 2021

The 1 : 1 type double salt of AgNO3 and NH4NO3 (NH4NO3 ⋅ AgNO3, compound 1) was prepared and its Raman spectrum was evaluated. IR and far‐IR spectra of compound 1 and its deuterated analog (ND4NO3 ⋅ AgNO3, compound 1‐D) were also studied. We identified two types of nitrate ions, one had a relatively strong, whereas the other is only weakly hydrogen bonded to the surrounding ammonium ions. The thermal decomposition features of compound 1 and its formation mechanism from [Ag(NH3)2]MnO4 (compound 2) at 80 °C with consecutive aqueous leaching of the decomposition residue has been elucidated. The solid phase decomposition product of compound 2 is presumably [Ag(NH3)NO3] (compound 3), which disproportionates into AgNO3 and [Ag(NH3)2]NO3 (compound 4). Compound 4 thermally decomposes in the solid phase into Ag+MnOx, while in aqueous solution its hydrolysis results in NH4NO3, which crystallizes out with an equimolar amount of AgNO3 formed during the disproportionation as compound 1.
t − b − τ Yukawa unification in non-holomorphic MSSM
Authors: Hiçyılmaz Yaşar
Published: April 2021

Abstract

We show that in the CMSSM with the non-holomorphic soft SUSY breaking terms, the Yukawa coupling unification of the third family fermions at the GUT scale, called t − b − τ Yukawa unification (YU), is possible under the recent collider and Dark Matter results. The YU parameter can also be found Rtbτ≈ 1, called perfect unification. We find that the squark masses exceed 3 TeV while the stau can be considerably lighter. In the case of YU, the tan β is in the interval [46,55]. We obtain bino-like dark matter (DM) of mass in the range of 0.6 TeV ≲ $$ {m}_{\upchi_1^0} $$

m

χ
1
0

≲ 1.3 TeV where the recent Dark Matter direct detection limits are also satisfied. We also identify A-resonance solutions which reduce the relic abundance of LSP neutralino down to the ranges compatible with the current Planck measurements.
Locally finite two-loop amplitudes for off-shell multi-photon production in electron-positron annihilation
Authors: Anastasiou Charalampos , Haindl Rayan , Sterman George , Yang Zhou , Zeng Mao
Published: April 2021

Abstract

We study the singularity structure of two-loop QED amplitudes for the production of multiple off-shell photons in massless electron-positron annihilation and develop counterterms that remove their infrared and ultraviolet divergences point by point in the loop integrand. The remainders of the subtraction are integrable in four dimensions and can be computed in the future with numerical integration. The counterterms capture the divergences of the amplitudes and factorize in terms of the Born amplitude and the finite remainder of the one-loop amplitude. They consist of simple one- and two-loop integrals with at most three external momenta and can be integrated analytically in a simple manner with established methods. We uncover novel aspects of fully local IR factorization, where vertex and self energy subdiagrams must be modified by new symmetrizations over loop momenta, in order to expose their tree-like tensor structures and hence factorization of IR singularities prior to loop integration. This work is a first step towards isolating locally the hard contributions of generic gauge theory amplitudes and rendering them integrable in exactly four dimensions with numerical methods.
Gauge invariant target space entanglement in D-brane holography
Authors: Das Sumit R. , Kaushal Anurag , Liu Sinong , Mandal Gautam , Trivedi Sandip P.
Published: April 2021

Abstract

It has been suggested in arXiv:2004.00613 that in Dp-brane holography, entanglement in the target space of the D-brane Yang-Mills theory provides a precise notion of bulk entanglement in the gravity dual. We expand on this discussion by providing a gauge invariant characterization of operator sub-algebras corresponding to such entanglement. This is achieved by finding a projection operator which imposes a constraint characterizing the target space region of interest. By considering probe branes in the Coloumb branch we provide motivation for why the operator sub-algebras we consider are appropriate for describing a class of measurements carried out with low-energy probes in the corresponding bulk region of interest. We derive expressions for the corresponding Renyi entropies in terms of path integrals which can be directly used in numerical calculations.
Modeling indicates degradation of mRNA and protein as a potential regulation mechanisms during cold acclimation
Authors: Krantz Maria , Legen Julia , Gao Yang , Zoschke Reimo , Schmitz-Linneweber Christian , Klipp Edda
Published: April 2021

Plants are constantly exposed to temperature fluctuations, which have direct effects on all cellular reactions because temperature influences reaction likelihood and speed. Chloroplasts are crucial to temperature acclimation responses of plants, due to their photosynthetic reactions whose products play a central role in plant metabolism. Consequently, chloroplasts serve as sensors of temperature changes and are simultaneously major targets of temperature acclimation. The core subunits of the complexes involved in the light reactions of photosynthesis are encoded in the chloroplast. As a result, it is assumed that temperature acclimation in plants requires regulatory responses in chloroplast gene expression and protein turnover. We conducted western blot experiments to assess changes in the accumulation of two photosynthetic complexes (PSII, and Cytb6f complex) and the ATP synthase in tobacco plants over two days of acclimation to low temperature. Surprisingly, the concentration of proteins within the chloroplast varied negligibly compared to controls. To explain this observation, we used a simplified Ordinary Differential Equation (ODE) model of transcription, translation, mRNA degradation and protein degradation to explain how the protein concentration can be kept constant. This model takes into account temperature effects on these processes. Through simulations of the ODE model, we show that mRNA and protein degradation are possible targets for control during temperature acclimation. Our model provides a basis for future directions in research and the analysis of future results.
Airborne fungi in Longyearbyen area (Svalbard, Norway) — case study
Authors: Pusz Wojciech , Urbaniak Jacek
Published: April 2021

Studies on the presence of atmospheric fungi in both Arctic and Antarctic polar areas are rare, and many of them were carried out briefly. Currently, when climate change is a fact, polar areas may be subject to various changes and fluctuations, negatively affecting sensitive polar ecosystems. The paper presents the results of tests on presence of fungi in the air over 30 years after the last investigations at the Svalbard Archipelago. A total of fifteen taxa of fungi were isolated in area of Longyearbyen, the majority of which were saprotrophic fungi of the genus Cladosporium that are associated with dead organic matter. Therefore, the presence of this taxon may be a good bioindicator of changes occurring in the Arctic environment, indirectly indicating the melting of glaciers and exposing increasingly larger areas inhabited by microorganisms, including fungi, which increase in number in the air. Additionally, the number of tourists visiting Longyearbyen is increasing, which may significantly affect the number and type of fungi in the air.
Preparation of bioactive glass nanoparticles with highly and evenly doped calcium ions by reactive flash nanoprecipitation
Authors: Ji Lijun , Xu Tong , Gu Jun , Liu Qingren , Zhou Shu , Shi Guojun , Zhu Zhengxi
Published: April 2021

Nanoscale bioactive glass particles have greater bioactivity than microscale bioactive glass particles, due to their high-specific surface area and fast ion release rate in body fluid. However, preparation of bioactive glass nanoparticles (BGNPs) is difficult since calcium is not easy to be highly doped into the forming silica atom network, leading to an uneven distribution and a low content of calcium. In addition, BGNPs are usually prepared in a dilute solution to avoid agglomeration of the nanoparticles, which decreases the production efficiency and increases the cost. In this work, BGNPs are prepared by a method of the reactive flash nanoprecipitation (RFNP) as well as a traditional sol–gel method. The results indicate that the BGNPs by the RFNP present a smaller size, narrower size distribution, more uniform composition, and better bioactivity than those by the traditional sol–gel method. The obtained BGNPs have uniform compositions close to the feed values. The high and even doping of calcium in the BGNPs is achieved. This successful doping of calcium into nanoparticles by the RFNP demonstrates a promising way to effectively generate high-quality BGNPs for bone repairs.
Swellable catheters based on a dynamic expanding inner diameter
Authors: Tennankore Rishabh , Brunette Margaret , Cox Tyler , Vazquez Rigoberto , Shikanov Ariella , Burns Michael L. , Love Brian
Published: April 2021

Intravenous (IV) fluid administration is critical for all patients undergoing care in a hospital setting. In-patient hospital practice, surgeries, and emergency care require functional IVs for fluid replacement and medication administration. Proper placement of IVs is vital to providing medical services. The ease of placement of an IV catheter, however, depends not only on the size of the catheter but also on provider experience and patient demographics such as age, body mass index, hydration status, and medical comorbidities present challenges to successful IV placement. Smaller diameter IV placement can improve success and there are instances where multiple small diameter catheters are placed for patient care when larger bore access is unattainable. Smaller inner-diameter catheters for anesthesia have functional constraints. Ideally, there would be a smaller catheter for placement that could function as a larger catheter for patient care. One solution is the idea of functionally responsive catheters. Here, we evaluated tubular-shaped hydrogels as potential functional catheters that can increase in inner diameter through fluid swelling using cross-linked homopolymers of polyacrylamide, PAM (10–40% w/w), and their copolymers with 0–8% w/w Poly-(Ethylene Glycol)-Diacrylate, PEGDA. For the PAM gels, the water transport mechanism was shown to be concentration-dependent Fickian diffusion, with the less concentrated gels exhibiting increasingly anomalous modes. Increasing the PEGDA content in the network yielded an initial high rate of water uptake, characterized by Case II transport. The swelling kinetics depended strongly on the sample geometry and boundary conditions. Initially, in a submerged swelling, the annulus expands symmetrically in both outward and inward directions (it thickens), reducing the internal diameter by up to 70%. After 1 h, however, the inner diameter increases steadily so that at equilibrium, there is a net (>100%) increase in all the dimensions of the tube. The amount of linear swelling at equilibrium depended only on the polymer volume fraction as made, while the rate of inner diameter expansion depended on the hydrophilicity of the matrix and the kinetics of sorption. This study serves as proof of concept to identify key parameters for the successful design of hydrogel-based catheter devices with expanding inner-diameters for applications in medical care.
A variational approach to the alternating projections method
Authors: De Bernardi Carlo Alberto , Miglierina Enrico
Published: April 2021

The 2-sets convex feasibility problem aims at finding a point in the nonempty intersection of two closed convex setsAandBin a Hilbert spaceH. The method of alternating projections is the simplest iterative procedure for finding a solution and it goes back to von Neumann. In the present paper, we study some stability properties for this method in the following sense: we consider two sequences of closed convex sets$$\{A_n\}$${An}and$$\{B_n\}$${Bn}, each of them converging, with respect to the Attouch-Wets variational convergence, respectively, toAandB. Given a starting point$$a_0$$a0, we consider the sequences of points obtained by projecting on the “perturbed” sets, i.e., the sequences$$\{a_n\}$${an}and$$\{b_n\}$${bn}given by$$b_n=P_{B_n}(a_{n-1})$$bn=PBn(an-1)and$$a_n=P_{A_n}(b_n)$$an=PAn(bn). Under appropriate geometrical and topological assumptions on the intersection of the limit sets, we ensure that the sequences$$\{a_n\}$${an}and$$\{b_n\}$${bn}converge in norm to a point in the intersection ofAandB. In particular, we consider both when the intersection$$A\cap B$$A∩Breduces to a singleton and when the interior of$$A \cap B$$A∩Bis nonempty. Finally we consider the case in which the limit setsAandBare subspaces.
Basic reading and reading-related language skills in adults with deficient reading comprehension who read a transparent orthography
Authors: Bar-Kochva Irit , Vágvölgyi Réka , Dresler Thomas , Nagengast Benjamin , Schröter Hannes , Schrader Josef , Nuerk Hans-Christoph
Published: April 2021

This study set out to examine the basic reading skills (accuracy and fluency in decoding, word and text reading) and some of the reading-related language skills (phonological awareness and rapid-naming) of 54 adults with low reading comprehension, who read the transparent German orthography. Participants were born in Germany and showed a typical non-verbal processing speed. With the exception of reading accuracy, participants were expected to present deficits in all basic reading and reading-related skills. The average performance in measures of decoding and word reading fluency was extremely low. A notable proportion of the sample, however, did not present a deficit in these measures. As expected, the average rate of reading errors was generally low. Nevertheless, text reading accuracy was deficient for one quarter of the sample. Tests addressing the reading-related language skills also indicated an average low performance in phonological awareness, but not in rapid-naming. Here too, a notable variance was observed. These results suggest that deficits in the basic reading skills and in phonological awareness characterise, on average, adults with low reading comprehension. At the same time, significant deficits in reading comprehension in this population do not necessarily imply deficits in the more basic skills of reading as well. In addition, the results indicate that reading accuracy constitutes a source of difficulty for some of these adults, despite the reading of a transparent orthography. The sources for the variance in performance throughout the different reading and reading-related measures remain to be explored.
SMFC as a tool for the removal of hydrocarbons and metals in the marine environment: a concise research update
Authors: Gambino Edvige , Chandrasekhar Kuppam , Nastro Rosa Anna
Published: April 2021

Marine pollution is becoming more and more serious, especially in coastal areas. Because of the sequestration and consequent accumulation of pollutants in sediments (mainly organic compounds and heavy metals), marine environment restoration cannot exempt from effective remediation of sediments themselves. It has been well proven that, after entering into the seawater, these pollutants are biotransformed into their metabolites, which may be more toxic than their parent molecules. Based on their bioavailability and toxic nature, these compounds may accumulate into the living cells of marine organisms. Pollutants bioaccumulation and biomagnification along the marine food chain lead to seafood contamination and human health hazards. Nowadays, different technologies are available for sediment remediation, such as physicochemical, biological, and bioelectrochemical processes. This paper gives an overview of the most recent techniques for marine sediment remediation while presenting sediment-based microbial fuel cells (SMFCs). We discuss the issues, the progress, and future perspectives of SMFC application to the removal of hydrocarbons and metals in the marine environment with concurrent energy production. We give an insight into the possible mechanisms leading to sediment remediation, SMFC energy balance, and future exploitation.
Initial phantom studies for an office-based low-field MR system for prostate biopsy
Authors: Chiragzada Selin , Hellman Eva , Michael Duncan , Narayanan Ram , Nacev Aleksandar , Kumar Dinesh
Published: April 2021

Purpose

Prostate cancer is the second most prevalent cancer in US men, with about 192,000 new cases and 33,000 deaths predicted for 2020. With only a 31% 5-year survival rate for patients with an initial diagnosis of stage-four prostate cancer, the necessity for early screening and diagnosis is clear. In this paper, we present navigation accuracy results for Promaxo’s MR system intended to be used in a physician’s office for image-guided transperineal prostate biopsy.

Methods

The office-based low-field MR system was used to acquire images of prostate phantoms with needles inserted through a transperineal template. Coordinates of the estimated sample core locations in the office-based MR system were compared to ground truth needle coordinates identified in a 1.5T external reference scan. The error was measured as the distance between the planned target and the ground truth core center and as the shortest perpendicular distance between the planned target and the ground truth trajectory of the whole core.

Results

The average error between the planned target and the ground truth core center was 2.57 ± 1.02 mm, [1.93–3.21] 95% CI. The average error between the planned target to the actual core segment was 2.05 ± 1.24 mm, [1.53–2.56] 95% CI.

Conclusion

The average navigation errors were below the clinically significant threshold of 5 mm. The initial phantom results demonstrate the feasibility of the office-based system for prostate biopsy.