bluuebunny/crossref_metadata_2025_split huggingface dataset:
Heterogeneous Carbonylative Sonogashira Reaction Based on Pd/g‐C3N4 Catalyst by Using Formic Acid as the CO Source
Authors: Huo Yong‐Wang , Qi Xinxin , Xu Tiefeng , Lu Wangyang , Wu Xiao‐Feng 
Published: July 2021

AbstractAlkynones represent one class of interesting building block which are frequently founded in a variety of biologically active compounds.[1] They have been emerged as key intermediates in the synthesis of various natural products and heterocycles.[2] Therefore, a considerable interest has been attracted and numerous strategies have been explored for the synthesis of alkynones. The traditional methods mainly rely on the reactions of acid chlorides with terminal alkynes.>[3–4] However, some drawbacks remain existing, including high reaction temperature, unstable acid chlorides, and poor functional group tolerance.
Facile Synthesis of Porous Hollow Cobalt‐Doped λ‐MnO2 Nano Architectures as a High‐performance Anode Material for Li‐ion Batteries and Li‐ion Hybrid Supercapacitors
Authors: Moon Ji S. , Nulu Arunakumari , Hwang Young G. , Nulu Venugopal , Sohn Keun Y. 
Published: July 2021

AbstractThe cost‐effectiveness and easy availability of MnO2 have attracted researchers′ attention as an anode electrode for LIBs over other transition metal oxides. However, MnO2 usage has been limited to its low reaction reversibility and poor conversion kinetics. Besides, Li‐ion hybrid supercapacitors (LiHSCs) are in urgent demand which offers higher power densities than LIBs without compromising energy density. Among different polymorphs of MnO2, λ‐MnO2, due to its 3D spinel structure, can be applied in many applications. Usually, λ‐MnO2 can be obtained by extracting lithium from LiMn2O4 using complex electrochemical or acid leaching methods. This study presents a modified Li2O2 assisted method to obtain cobalt‐doped 3D architectures of λ‐MnO2 porous hollow nanostructures. The resultant MnxCo1‐xOy hollow structures with 5 % cobalt addition are used as anode for LIBs exhibited excellent charge reversibility and cycle stability over thousands of reaction cycles. This result is known to be one of the finest among MnO2 anodes reported to date. Also, a LiHSC device is fabricated with MnxCo1‐xOy hollow structures as anode and the device exhibits an excellent comprehensive electrochemical performance in terms of high operating voltage (4.2 V), with a specific cell capacity of 33 mAh g−1 at a high current density of 5 A g−1 and achieved the maximum power density of 12261 W kg−1 (with energy density at 81.7 Wh kg−1) with long cycle life.
Self‐Healing Functional Electronic Devices
Authors: Gai Yansong , Li Hu , Li Zhou 
Published: July 2021

AbstractElectronic devices with various functions bring great convenience and revolutionize the way we live. They are inevitable to degrade over time because of physical or chemical fatigue and damage during practical operation. To make these devices have the ability to autonomously heal from cracks and restore their mechanical and electrical properties, self‐healing materials emerged as the time requires for constructing robust and self‐healing electronic devices. Here the development of self‐healing electronic devices with different functions, for example, energy harvesting, energy storage, sensing, and transmission, is reviewed. The new application scenarios and existing challenges are explored, and possible strategies and perspectives for future practical applications are discussed.
Effect of natural rubber latex on the shrinkage behavior and porosity of geopolymer concrete
Authors: Rath Badrinarayan 
Published: July 2021

AbstractShrinkage‐reducing admixture has been proved as the best solution to reduce the shrinkage cracks on the surface of the concrete. Various shrinkage‐reducing admixtures available in the local market are chemical, highly hazardous, and limited use in concrete. In the present research, rubber latex was used by replacing water up to 2% in geopolymer concrete. Volumetric shrinkage for geopolymer concrete with different doses of rubber latex was determined and compared those results with traditional cement concrete of the same mix. The relation between volumetric shrinkage and porosity of concrete was studied at a deep level. It was found that a large number of micropores of concrete were reduced by using 2% of rubber latex resulting in decrease in shrinkage significantly. By using rubber latex in concrete, a hazardous expensive chemical shrinkage‐reducing admixture can be replaced by a low‐cost nonhazardous organic substance.
Normal form of nilpotent vector field near the tip of the pure spinor cone
Authors: Mikhailov Andrei , Zavaleta Dennis 
Published: July 2021

Abstract
Pure spinor formalism implies that supergravity equations in space-time are equivalent to the requirement that the worldsheet sigma-model satisfies certain properties. Here we point out that one of these properties has a particularly transparent geometrical interpretation. Namely, there exists an odd nilpotent vector field on some singular supermanifold, naturally associated to space-time. Is it true that all supergravity fields are encoded in this vector field, as coefficients in its normal form, and the nilpotence is equivalent to the target space equations of motion? We show that this is approximately correct. The normal form is parametrized by some tensor fields, which satisfy hyperbolic equations. These equations are slightly weaker than the full supergravity equations.
Vortex precession and exchange in a Bose-Einstein condensate
Authors: Garaud Julien , Dai Jin , Niemi Antti J. 
Published: July 2021

Abstract
Vortices in a Bose-Einstein condensate are modelled as spontaneously symmetry breaking minimum energy solutions of the time dependent Gross-Pitaevskii equation, using the method of constrained optimization. In a non-rotating axially symmetric trap, the core of a single vortex precesses around the trap center and, at the same time, the phase of its wave function shifts at a constant rate. The precession velocity, the speed of phase shift, and the distance between the vortex core and the trap center, depend continuously on the value of the conserved angular momentum that is carried by the entire condensate. In the case of a symmetric pair of identical vortices, the precession engages an emergent gauge field in their relative coordinate, with a flux that is equal to the ratio between the precession and shift velocities.
Assessment of myelination in infants and young children by T1 relaxation time measurements using the magnetization-prepared 2 rapid acquisition gradient echoes sequence
Authors: Kühne Fabienne , Neumann Wolf-Julian , Hofmann Philip , Marques José , Kaindl Angela M. , Tietze Anna 
Published: July 2021

Abstract
Background
Axonal myelination is an important maturation process in the developing brain. Increasing myelin content correlates with the longitudinal relaxation rate (R1=1/T1) in magnetic resonance imaging (MRI).

Objective
By using magnetization-prepared 2 rapid acquisition gradient echoes (MP2RAGE) on a 3-T MRI system, we provide R1 values and myelination rates for infants and young children.

Materials and methods
Average R1 values in white and grey matter regions in 94 children without pathological MRI findings (age range: 3 months to 6 years) were measured and fitted by a saturating-exponential growth model. For comparison, R1 values of 36 children with different brain pathologies are presented. The findings were related to a qualitative evaluation using T2, magnetization-prepared rapid acquisition gradient echo (MP-RAGE) and MP2RAGE.

Results
R1 changes rapidly in the first 16 months of life, then much slower thereafter. R1 is highest in pre-myelinated structures in the youngest subjects, such as the posterior limb of the internal capsule (0.74–0.76±0.04 s−1) and lowest for the corpus callosum (0.37–0.44±0.03 s−1). The myelination rate is fastest in the corpus callosum and slowest in the deep grey matter. R1 is decreased in hypo- and dysmyelination disorders. Myelin maturation is clearly visible on MP2RAGE, especially in the first year of life.

Conclusion
MP2RAGE permits a quantitative R1 mapping method with an examination time of approximately 6 min. The age-dependent R1 values for children without MRI-identified brain pathologies are well described by a saturating-exponential function with time constants depending on the investigated brain region. This model can serve as a reference for this age group and to search for indications of subtle pathologies. Moreover, the MP2RAGE sequence can also be used for the qualitative assessment of myelinated structures.
Analysis of imaging biomarkers and retinal nerve fiber layer thickness in RPGR-associated retinitis pigmentosa
Authors: Birtel Theresa H. , Birtel Johannes , Hess Kristina , Clemens Amelie C. , Lindner Moritz , Herrmann Philipp , Holz Frank G. , Gliem Martin 
Published: July 2021

Abstract
Purpose
To investigate multimodal retinal imaging characteristics including the retinal nerve fiber layer (RNFL) thickness in patients with RPGR-associated retinitis pigmentosa (RP).

Methods
This cross-sectional case–control study included 17 consecutive patients (median age, 21 years) with RPGR-associated RP who underwent retinal imaging including optical coherence tomography (OCT), short-wavelength fundus autofluorescence (AF) imaging, and RNFL scans centered on the optic disc. RNFL thickness was manually segmented and compared to clinical and imaging parameters including the transfoveal ellipsoid zone (EZ) width, the horizontal diameter of the macular hyperautofluorescent ring. RNFL thickness was compared to 17 age- and sex-matched controls.

Results
In patients with RPGR-associated RP, the EZ width (R2 = 0.65), the central hyperautofluorescent ring on AF images (R2 = 0.72), and visual acuity (R2 = 0.68) were negatively correlated with age. In comparison to controls, a significantly (p < 0.0001) increased global RNFL thickness was identified in RPGR-associated RP, which was, however, less pronounced in progressed disease as indicated by the EZ width or the diameter of the central hyperautofluorescent ring.

Conclusions
This study describes retinal characteristics in patients with RPGR-associated RP including a pronounced peripapillary RNFL thickness compared to healthy controls. These results contribute to the knowledge about imaging biomarkers in RP, which might be of interest for therapeutic approaches such as gene replacement therapies.
Comorbidity, cognitive dysfunction, physical functioning, and quality of life in older breast cancer survivors
Authors: Crouch Adele , Champion Victoria L. , Von Ah Diane 
Published: July 2021

Abstract
Purpose
Older breast cancer survivors (BCS) may be at greater risk for cognitive dysfunction and other comorbidities; both of which may be associated with physical and emotional well-being. This study will seek to understand these relationships by examining the association between objective and subjective cognitive dysfunction and physical functioning and quality of life (QoL) and moderated by comorbidities in older BCS.

Methods
A secondary data analysis was conducted on data from 335 BCS (stages I–IIIA) who were ≥ 60 years of age, received chemotherapy, and were 3–8 years post-diagnosis. BCS completed a one-time questionnaire and neuropsychological tests of learning, delayed recall, attention, working memory, and verbal fluency. Descriptive statistics and separate linear regression analyses testing the relationship of each cognitive assessment on physical functioning and QoL controlling for comorbidities were conducted.

Results
BCS were on average 69.79 (SD = 3.34) years old and 5.95 (SD = 1.48) years post-diagnosis. Most were stage II (67.7%) at diagnosis, White (93.4%), had at least some college education (51.6%), and reported on average 3 (SD = 1.81) comorbidities. All 6 physical functioning models were significant (p < .001), with more comorbidities and worse subjective attention identified as significantly related to decreased physical functioning. One model found worse subjective attention was related to poorer QoL (p < .001). Objective cognitive function measures were not significantly related to physical functioning or QoL.

Conclusions
A greater number of comorbidities and poorer subjective attention were related to poorer outcomes and should be integrated into research seeking to determine predictors of physical functioning and QoL in breast cancer survivors.
Data-driven deep density estimation
Authors: Puchert Patrik , Hermosilla Pedro , Ritschel Tobias , Ropinski Timo 
Published: July 2021

AbstractDensity estimation plays a crucial role in many data analysis tasks, as it infers a continuous probability density function (PDF) from discrete samples. Thus, it is used in tasks as diverse as analyzing population data, spatial locations in 2D sensor readings, or reconstructing scenes from 3D scans. In this paper, we introduce a learned, data-driven deep density estimation (DDE) to infer PDFs in an accurate and efficient manner, while being independent of domain dimensionality or sample size. Furthermore, we do not require access to the original PDF during estimation, neither in parametric form, nor as priors, or in the form of many samples. This is enabled by training an unstructured convolutional neural network on an infinite stream of synthetic PDFs, as unbound amounts of synthetic training data generalize better across a deck of natural PDFs than any natural finite training data will do. Thus, we hope that our publicly available DDE method will be beneficial in many areas of data analysis, where continuous models are to be estimated from discrete observations.
A Cross-Sectional Study to Evaluate the Effects of Age and Duration of HIV Infection on Anxiety and Depression in Cisgender Men
Authors: Gianella Sara , Saloner Rowan , Curtin Genevieve , Little Susan J. , Heaton Anne , Montoya Jessica L. , Letendre Scott L. , Marquine María J. , Jeste Dilip V. , Moore David J. 
Published: July 2021

AbstractThis observational cross-sectional study of 152 people with HIV (PWH) examined the effects of age and estimated duration of HIV infection (EDI) on depressive and anxiety symptoms. All participants were cisgender men and completed the Profile of Moods State (POMS), a self-report inventory of current (i.e., past week) mood states. Overall, study results confirmed higher levels of anxiety and depression in PWH compared to individuals without HIV. Age group (< 50 or ≥ 50 years) moderated the effect of EDI (< 3 or ≥ 3 years) on mood disturbance. Specifically, younger PWH with early diagnosed infection exhibited the highest levels of depression and anxiety, whereas depression and anxiety were attenuated in older PWH with early infection such that their POMS scores did not significantly differ from the HIV-negative and chronically HIV-infected groups. Despite the small sample size and other important limitations in our study design, our preliminary findings confirm previous observations that older people may have some adaptive ability to better handle the acute psychological stressors associated with recent HIV infection.
A simple model for desulphurisation of flue gas using reactive filters
Authors: Breward Chris , Kiradjiev Kristian 
Published: July 2021

AbstractDesulphurisation of flue gas is essential before it can be released safely into the atmosphere. One way of removing sulphur dioxide is to use a purification device incorporating a reactive filter, in which the flue gas stream passes in front of a porous-catalyst-filled structure which converts the gaseous sulphur dioxide into liquid sulphuric acid. In this paper, we build and solve a simple mathematical model to describe the operation of a paradigm reactive filter. Our model captures the transport of sulphur dioxide through the device via advection in the main “outer” flow and diffusion through the catalyst structure along with the production of sulphuric acid. This sulphuric acid gradually accumulates in the filter rendering it less efficient. We determine the clogging time for an individual channel (that is, the time at which the entrance to the channel becomes completely filled with liquid) and explore how the concentrations of sulphur dioxide and oxygen and the thickness of the sulphuric acid layer change as the key dimensionless parameters are varied, comparing numerical and asymptotic results where appropriate. We then turn our attention to the device scale and solve our model numerically to determine the overall lifetime of the device. We vary the key dimensionless parameters and explore how they affect the efficiency of the device. In the physically relevant parameter regime, we find an explicit solution to the outer flow problem which agrees well with numerical solutions and provides a formula for the lifetime of the device. Finally, we propose a formula for determining the catalyst reaction rate, given data on the concentration of sulphur dioxide exiting the device.
Copper ore post-flotation settling tanks in Poland: social acceptance or objection?
Authors: Pactwa Katarzyna , Górniak-Zimroz Justyna 
Published: July 2021

AbstractThe issues concerning mining have been causing a wide variety of emotions. Objection to and disagreement with new investments, but also social acceptance for the operation of mining plants offering stable employment. Production in this sector is associated with the generation of waste. In the case of copper ore mining, the result of the entrepreneur's activity consists of waste treatment facilities in the form of post-flotation settling tanks. In addition to the inactive facilities in Lower Silesia, there is also the settling tank Zelazny Most, which is used and expanded. The large area and risk to the environment allow to suppose that the existence of settling tanks in social space generates conflicts or it is conducive to the emigration of the residents. In order to verify the above-mentioned hypothesis, the authors used geographic information systems to analyse the current population status and expansion of the road and rail network, the residents’ drinking water sources and soil permeability in five impact zones. The achieved results allow to conclude that the facilities belonging to KGHM PM S.A. coexist with their surroundings, thus gaining social acceptance. The proposed research methodology can be used by the entrepreneurs, but also local authorities to evaluate the acceptance of mining waste disposal facilities.
The place of vericiguat in the landscape of treatment for heart failure with reduced ejection fraction
Authors: Aimo Alberto , Castiglione Vincenzo , Vergaro Giuseppe , Panichella Giorgia , Senni Michele , Lombardi Carlo Mario , Emdin Michele 
Published: July 2021

AbstractThe significant morbidity and mortality associated with heart failure with reduced (HFrEF) or preserved ejection fraction (HFpEF) justify the search for novel therapeutic agents. The nitric oxide (NO)–soluble guanylate cyclase (sGC)-cyclic guanosine monophosphate (cGMP) pathway plays an important role in the regulation of cardiovascular function. This pathway is disrupted in HF resulting in decreased protection against myocardial injury. The sGC activator cinaciguat increases cGMP levels by direct, NO-independent activation of sGC, and may be particularly effective in conditions of increased oxidative stress and endothelial dysfunction, and then reduced NO levels, but this comes at the expense of a greater risk of hypotension. Conversely, sGC stimulators (riociguat and vericiguat) enhance sGC sensitivity to endogenous NO, and then exert a more physiological action. The phase 3 VICTORIA trial found that vericiguat is safe and effective in patients with HFrEF and recent HF decompensation. Therefore, adding vericiguat may be considered in individual patients with HFrEF, particularly those at higher risk of HF hospitalization; the efficacy of the sacubitril/valsartan-vericiguat combination in HFrEF is currently unknown.
The application of a phycocyanin extract obtained from Arthrospira platensis as a blue natural colorant in beverages
Authors: García Ana Belén , Longo Eleonora , Bermejo Ruperto 
Published: July 2021

AbstractCurrently, the food additive industry has interest in replacing artificial dyes with natural pigments, trying to maintain consumer interest and increase their awareness towards healthy diets. Phycobiliproteins are light-harvesting and water-soluble proteins extracted from cyanobacteria and red algae that can be employed as natural additives. In the present work, a C-phycocyanin extract from the cyanobacterium Arthrospira platensis was tested as blue colorant in beverages to demonstrate that samples containing the protein extract have a color similar to marketed beverages containing synthetic dyes. Using spectroscopy and colorimetry, the extract was characterized and gave evidence of having good properties and good stability in the pH range between 3.0 and 9.0. The staining factors, representing the amount of blue protein needed to reproduce the color of bluish commercial samples, ranged between 15.6 and 111.7 mg·L−1, being sufficiently low in all samples. Additionally, color stability during a short period of cold storage was studied: it demonstrated that isotonic and tonic beverages remained stable throughout the 11-days analysis period with no significant changes. These results prove that the C-phycocyanin extract has potential applications in food as natural colorant, being an alternative option to synthetic coloring molecules.
Scheduling with gaps: new models and algorithms
Authors: Chrobak Marek , Golin Mordecai , Lam Tak-Wah , Nogneng Dorian 
Published: July 2021

AbstractWe consider scheduling problems for unit jobs with release times, where the number or size of the gaps in the schedule is taken into consideration, either in the objective function or as a constraint. Except for several papers on minimum-energy scheduling, there is no work in the scheduling literature that uses performance metrics depending on the gap structure of a schedule. One of our objectives is to initiate the study of such scheduling problems. We focus on the model with unit-length jobs. First we examine scheduling problems with deadlines, where we consider two variants of minimum-gap scheduling: maximizing throughput with a budget for the number of gaps and minimizing the number of gaps with a throughput requirement. We then turn to other objective functions. For example, in some scenarios gaps in a schedule may be actually desirable, leading to the problem of maximizing the number of gaps. A related problem involves minimizing the maximum gap size. The second part of the paper examines the model without deadlines, where we focus on the tradeoff between the number of gaps and the total or maximum flow time. For all these problems we provide polynomial time algorithms, with running times ranging from $$O(n\log n)$$

O
(
n
log
n
)

for some problems to $$O(n^7)$$

O
(

n
7

)

for other. The solutions involve a spectrum of algorithmic techniques, including different dynamic programming formulations, speed-up techniques based on searching Monge arrays, searching $$X+Y$$

X
+
Y

matrices, or implicit binary search. Throughout the paper, we also draw a connection between gap scheduling problems and their continuous analogues, namely hitting set problems for intervals of real numbers. As it turns out, for some problems the continuous variants provide insights leading to efficient algorithms for the corresponding discrete versions, while for other problems completely new techniques are needed to solve the discrete version.