bluuebunny/crossref_metadata_2025 huggingface dataset:
A note on non-commutative polytopes and polyhedra
Authors: Huber Beatrix , Netzer Tim
Published: January 2021

It is well-known that every polyhedral cone is finitely generated (i.e. polytopal), and vice versa. Surprisingly, the two notions differ almost always for non-commutative versions of such cones, as was recently proved by different authors. In this note we give a direct and constructive proof of the statement. Our proof yields a new and surprising quantitative result: the difference of the two notions can always be seen at the first level of non-commutativity, i.e. for matrices of size 2, independent of dimension and complexity of the initial convex cone.
Sustainability Disclosure and the Financialization of Social Sustainability
Authors: Woschnack Daniela , Hiss Stefanie , Nagel Sebastian , Teufel Bernd
Published: January 2021

This empirical study explores the financialization of social sustainability driven by sustainability accounting and reporting initiatives (SARIs). Since no globally accepted definition of what social sustainability encompasses exists, the paper asks how social sustainability is translated into the financial market language by SARIs as they provide standards for disclosing corporate non-financial performance and promote their concepts of social sustainability. The paper uses a two-step qualitative content analysis. First, it operationalizes social sustainability based on the empirical data of six sustainability rating agencies. Second, this operationalization is compared with the concepts created by three SARIs. The paper shows significant differences between the concepts of the SARIs and the rating agencies. While the rating agencies altogether interpret social sustainability with 83 distinct aspects, the SARIs, although differently created, use significant reduced concepts where 20% of these aspects are absent. The result of this financialization process could be a simplified and financially determined concept of social sustainability within die socially discourse. The research is limited to social sustainability and its financialization by SARIs. Individual indicators and their way or intensity to capture aspects of social sustainability were not part of the research interest. Further research should investigate the economic and the ecological pillars of sustainability as well as the usage of such financialized concepts within the society and especially by corporations. The paper unfolds the arbitrariness of operationalizing a qualitative phenomenon like social sustainability through the financial system. It discloses the need for looking at the mechanisms behind such processes and at the interests of the actors behind the frameworks. The paper reveals the financialization process driven by SARIs and demonstrates its simplifying effects on the concept of social sustainability. Furthermore, the paper shows that SARIs as metrics for non-financial aspects are troubled with a lack of transparency and a lack of convergence.
Blowing-up solutions of the time-fractional dispersive equations
Authors: Alsaedi Ahmed , Ahmad Bashir , Kirane Mokhtar , Torebek Berikbol T.
Published: January 2021

This paper is devoted to the study of initial-boundary value problems for time-fractional analogues of Korteweg-de Vries, Benjamin-Bona-Mahony, Burgers, Rosenau, Camassa-Holm, Degasperis-Procesi, Ostrovsky and time-fractional modified Korteweg-de Vries-Burgers equations on a bounded domain. Sufficient conditions for the blowing-up of solutions in finite time of aforementioned equations are presented. We also discuss the maximum principle and influence of gradient non-linearity on the global solvability of initial-boundary value problems for the time-fractional Burgers equation. The main tool of our study is the Pohozhaev nonlinear capacity method. We also provide some illustrative examples.
Nonexistence of Solutions for Dirichlet Problems with Supercritical Growth in Tubular Domains
Authors: Molle Riccardo , Passaseo Donato
Published: January 2021

We deal with Dirichlet problems of the form

{

Δ
⁢
u

+

f
⁢

(
u
)

=
0

in 
⁢
Ω

,

u

=
0

on 
⁢

∂
⁡
Ω

,

\left\{\begin{aligned} \displaystyle{}\Delta u+f(u)&\displaystyle=0&&% \displaystyle\phantom{}\text{in }\Omega,\\ \displaystyle u&\displaystyle=0&&\displaystyle\phantom{}\text{on }\partial% \Omega,\end{aligned}\right.

where Ω is a bounded domain of

ℝ
n

{\mathbb{R}^{n}}

,

n
≥
3

{n\geq 3}

, and f has supercritical growth from the viewpoint of Sobolev embedding. In particular, we consider the case where Ω is a tubular domain

T
ε

⁢

(

Γ
k

)

{T_{\varepsilon}(\Gamma_{k})}

with thickness

ε
>
0

{{\varepsilon}>0}

and center

Γ
k

{\Gamma_{k}}

, a k-dimensional, smooth, compact submanifold of

ℝ
n

{\mathbb{R}^{n}}

. Our main result concerns the case where

k
=
1

{k=1}

and

Γ
k

{\Gamma_{k}}

is contractible in itself. In this case we prove that the problem does not have nontrivial solutions for

ε
>
0

{{\varepsilon}>0}

small enough. When

k
≥
2

{k\geq 2}

or

Γ
k

{\Gamma_{k}}

is noncontractible in itself we obtain weaker nonexistence results. Some examples show that all these results are sharp for what concerns the assumptions on k and f.
A Qualitative Study of (p,q) Singular Parabolic Equations: Local Existence, Sobolev Regularity and Asymptotic Behavior
Authors: Giacomoni Jacques , Kumar Deepak , Sreenadh Konijeti
Published: January 2021

The purpose of the article is to study the existence, regularity, stabilization and blow-up results of weak solution to the following parabolic(p,q){(p,q)}-singular equation:

($\mathrm{P}_{t}$){ut-Δp⁢u-Δq⁢u=ϑ⁢u-δ+f⁢(x,u),u>0in ⁢Ω×(0,T),u=0on ⁢∂⁡Ω×(0,T),u⁢(x,0)=u0⁢(x)in ⁢Ω,\displaystyle{}\left\{\begin{aligned} \displaystyle{}u_{t}-\Delta_{p}u-\Delta_% {q}u&\displaystyle=\vartheta u^{-\delta}+f(x,u),\quad u>0&&\displaystyle% \phantom{}\text{in }\Omega\times(0,T),\\ \displaystyle u&\displaystyle=0&&\displaystyle\phantom{}\text{on }\partial% \Omega\times(0,T),\\ \displaystyle u(x,0)&\displaystyle=u_{0}(x)&&\displaystyle\phantom{}\text{in }% \Omega,\end{aligned}\right.

where Ω is a bounded domain inℝN{\mathbb{R}^{N}}withC2{C^{2}}boundary∂⁡Ω{\partial\Omega},1<q
0{0<\delta,T>0},N≥2{N\geq 2}andϑ>0{\vartheta>0}is a parameter. Moreover, we assume thatf:Ω×[0,∞)→ℝ{f:\Omega\times[0,\infty)\to\mathbb{R}}is a bounded below Carathéodory function, locally Lipschitz with respect to the second variable uniformly inx∈Ω{x\in\Omega}andu0∈L∞⁢(Ω)∩W01,p⁢(Ω){u_{0}\in L^{\infty}(\Omega)\cap W^{1,p}_{0}(\Omega)}. We distinguish the cases asq-subhomogeneous andq-superhomogeneous depending on the growth off(hereafter we will drop the termq). In the subhomogeneous case, we prove the existence and uniqueness of the weak solution to problem (Pt{\mathrm{P}_{t}}) forδ<2+1p-1{\delta<2+\frac{1}{p-1}}. For this, we first study the stationary problems corresponding to (Pt{\mathrm{P}_{t}}) by using the method of sub- and supersolutions and subsequently employing implicit Euler method, we obtain the existence of a solution to (Pt{\mathrm{P}_{t}}). Furthermore, in this case, we prove the stabilization result, that is, the solutionu⁢(t){u(t)}of (Pt{\mathrm{P}_{t}}) converges tou∞{u_{\infty}}, the unique solution to the stationary problem, inL∞⁢(Ω){L^{\infty}(\Omega)}ast→∞{t\rightarrow\infty}. For the superhomogeneous case, we prove the local existence theorem by taking help of nonlinear semigroup theory. Subsequently, we prove finite time blow-up of solution to problem (Pt{\mathrm{P}_{t}}) for small parameterϑ>0{\vartheta>0}in the caseδ≤1{\delta\leq 1}and for allϑ>0{\vartheta>0}in the caseδ>1{\delta>1}. Moreover, we prove higher Sobolev integrability of the solution to purely singular problem corresponding to the steady state of (Pt{\mathrm{P}_{t}}), which is of independent interest. As a consequence of this, we improve the Sobolev regularity of solution to (Pt{\mathrm{P}_{t}}) for the caseδ<2+1p-1{\delta<2+\frac{1}{p-1}}.
Construction of Solutions for Hénon-Type Equation with Critical Growth
Authors: Guo Yuxia , Liu Ting
Published: January 2021

We consider the following Hénon-type problem with critical growth:

(H)

{

-

Δ
⁢
u

=

K
⁢

(

|

y
′

|

,

y
′′

)

⁢

u

2
*

-
1

,

u
>
0

in 
⁢

B
1

,

u

=
0

on 
⁢

∂
⁡

B
1

,

\displaystyle{}\left\{\begin{aligned} \displaystyle{}-\Delta u&\displaystyle=K% (|y^{\prime}|,y^{\prime\prime})u^{2^{*}-1},\quad u>0&&\displaystyle\text{in }B% _{1},\\ \displaystyle u&\displaystyle=0&&\displaystyle\text{on }\partial B_{1},\end{% aligned}\right.

where

2
*

=

2
⁢
N

N
-
2

{2^{*}\kern-1.0pt=\kern-1.0pt\frac{2N}{N-2}}

,

N
≥
5

{N\kern-1.0pt\geq\kern-1.0pt5}

,

B
1

{B_{1}}

is the unit sphere in

ℝ
N

{\mathbb{R}^{N}}

,

y
=

(

y
′

,

y
′′

)

∈

ℝ
2

×

ℝ

N
-
2

y\kern-1.0pt=\kern-1.0pt(y^{\prime},y^{\prime\prime})\kern-1.0pt\in\kern-1.0pt% \mathbb{R}^{2}\times\mathbb{R}^{N-2}

,

r
=

|

y
′

|

{r\kern-1.0pt=\kern-1.0pt|y^{\prime}|}

and

K
⁢

(
y
)

=

K
⁢

(
r
,

y
′′

)

∈

C
2

⁢

(

B
1

)

{K(y)\kern-1.0pt=\kern-1.0ptK(r,y^{\prime\prime})\kern-1.0pt\in\kern-1.0ptC^{2% }(B_{1})}

is a bounded non-negative function. By using a finite reduction argument and local Pohozaev-type identities, we prove that if

N
≥
5

{N\geq 5}

and

K
⁢

(
r
,

y
′′

)

{K(r,y^{\prime\prime})}

has a stable critical point

y
0

=

(

r
0

,

y
0
′′

)

∈

∂
⁡

B
1

{y_{0}=(r_{0},y_{0}^{\prime\prime})\in\partial B_{1}}

, then the above problem has infinitely many solutions, whose energy can be arbitrarily large.
Ein hybrides RNN-Modell für die mittel- bis langfristige Vorhersage des Strombedarfs unter Berücksichtigung von Wettereinflüssen
Authors: Jieyang Peng , Dongkun Wang , Kimmig Andreas , Langovoy Mikhail A. , Jiahai Wang , Ovtcharova Jivka
Published: January 2021

Im täglichen Stadtbetrieb sollte die Stromversorgung unterbrechungsfrei sein, was das moderne Energiemanagement vor Herausforderungen stellt. Die Prognose des Energiebedarfs kann die Strategie des Energiemanagements optimieren und die Energieeffizienz verbessern. Das traditionelle LSTM-Modell, das auf einer Codierungs-Decodierungs-Struktur basiert, codiert alle historischen Informationen als Vektor fester Länge, was zum Informationsverlust führt, wenn der vorhergesagte Wert von den Merkmalen abhängt die weit in der Vergangenheit liegen. Dies ist bei Energieprognosen aufgrund der Periodizität des Energieverbrauchs üblich. Um das oben genannte Problem zu lösen und das Potenzial der Betriebsdaten von Kraftwerken für Energievorhersagen vollständig auszuschöpfen, wird in diesem Artikel ein Energievorhersagemodell vorgeschlagen, das auf dem Aufmerksamkeitsmechanismus basiert. Ausgehend von der traditionellen Codierungs-Decodierungs-Architektur wird der räumliche und zeitliche Aufmerksamkeitsmechanismus eingeführt, um die räumlichen und zeitlichen Eigenschaften, die für den vorhergesagten Wert am relevantesten sind, adaptiv auszuwählen. Die experimentellen Ergebnisse zeigen, dass bei der Vorhersage des Strombedarfs von Shanghai für die nächsten 100 Tage, der Fehler des Hybridmodells 25,8 % niedriger ist als der des traditionellen LSTM-Modells. Darüber hinaus zeigt der Fehlertrend des Hybridmodells im Laufe der Zeit auch eine stärkere Stabilität als das herkömmliche Modell.
UFIR-Parameteridentifikation in Echtzeit bei fehlenden Messungen
Authors: Siegl Steffen , Svaricek Ferdinand
Published: January 2021

In diesem Bericht wird ein erwartungstreues Filter mit endlicher Impulsantwort (Unbiased Finite Impulse Response/UFIR) zur Systemidentifikation mittels Parameterschätzung verwendet. Dieses entspricht einem Least-Squares-Verfahren auf bewegtem Horizont (Receding Horizon Least Squares/RHLS) ohne die Verwendung von Anfangsbedingungen und mit optimaler Horizontlänge für eine minimale Schätzfehlerkovarianz in Gegenwart von Parameter- und Messrauschen. Die Messwerte des Ausgangssignals werden von der Strecke über ein Netzwerk [basierend auf dem Transmission Control Protocol (TCP)] zum Parameterschätzer übertragen. Die dabei stochastisch auftretenden Paketverluste werden mit Hilfe multipler Imputationen kompensiert. Der Einfluss des Netzwerks auf die Schätzgüte wird untersucht und an einem numerischen Beispiel erläutert.
Industrial autonomous systems: a survey on definitions, characteristics and abilities
Authors: Müller Manuel , Müller Timo , Ashtari Talkhestani Behrang , Marks Philipp , Jazdi Nasser , Weyrich Michael
Published: January 2021

Autonomous systems are increasingly discussed in the domain of industrial automation. However, there is no consensus in the literature about the definition of industrial autonomous systems, what characteristics do they possess and how to distinguish them from intelligent industrial automation systems. Another important aspect is the comparison between the degree of automation and autonomy. Addressing this confusion, this paper starts with an analysis of the historical development of the term autonomy. Based on the similarities in the definitions, that were identified in a literature review, a comprehensive definition of industrial autonomous systems is presented, and four main characteristics of an industrial autonomous system are derived. Consequently, the characteristics for the realization of an industrial autonomous system (1) systematic process execution, (2) adaptability, (3) self-governance and (4) self-containedness are described in detail. Another objective of this contribution is to assist the developers of industrial autonomous systems to take the above-mentioned characteristics into account. Furthermore, the developer is advised which abilities can be used to achieve the corresponding essential characteristics of industrial autonomous systems. To illustrate the characteristics and abilities of an industrial autonomous system, this paper gives a detailed description of three realized cases of application in industry.
Do Large Corporate Tax Cuts Boost Wages? Evidence from Ohio
Authors: Kakpo Eliakim
Published: January 2021

This paper evaluates a natural experiment which occurred in Ohio in 2005 when the state amended the tax system. The change sets up a dramatic corporate tax cut of 8.3 percentage points (p.p.) over the period 2006–2010 corresponding to a 96.9% reduction in the tax. Policymakers also reduced the personal income tax over the same period by 0.95 percentage point (p.p.). I investigate the incidence of the reform on wages in general and corporate wages in the short-run. To do so, I use a synthetic control method along with an event study design applied to individual records of the Current Population Survey (CPS). The results in this paper suggest that the corporate tax cut may have resulted in a one-time payment in corporate wages at the onset of the reform.
Tacit Collusion with Consumer Preference Costs
Authors: Roig Guillem
Published: January 2021

When consumers have preference costs, two opposing effects need to be assessed to analyse the incentives of firms to set collusive prices. On the one hand, preference costs make a deviation from collusion less attractive, as the deviating firm must offer a large enough discount to cover the preference costs. On the other hand, preference costs lock in consumers and make punishment from rivals less effective. When preference costs are low, the latter of the two effects dominates and collusion is more challenging to sustain than in a situation with no preference costs. With high enough preference costs, collusion is a (weakly) dominant strategy. These results do not eventuate in a model with switching costs.
Research progress on the mechanism of orexin in pain regulation in different brain regions
Authors: Kang Xianhui , Tang Hongli , Liu Yao , Yuan Yan , Wang Mi
Published: January 2021

Orexin is a neuropeptide that is primarily synthesized and secreted by the lateral hypothalamus (LH) and includes two substances derived from the same precursor (orexin A [OXA] and orexin B [OXB]). Studies have shown that orexin is not only involved in the regulation of eating, the sleep–wake cycle, and energy metabolism, but also closely associated with various physiological functions, such as cardiovascular control, reproduction, stress, reward, addiction, and the modulation of pain transmission. At present, studies that have been performed both domestically and abroad have confirmed that orexin and its receptors are closely associated with pain regulation. In this article, the research progress on acute pain regulation involving orexin is reviewed.
Green fabrication of Co and Co3O4 nanoparticles and their biomedical applications: A review
Authors: Waris Abdul , Din Misbahud , Ali Asmat , Afridi Shakeeb , Baset Abdul , Khan Atta Ullah , Ali Muhammad
Published: January 2021

Nanotechnology is the fabrication, characterization, and potential application of various materials at the nanoscale. Over the past few decades, nanomaterials have attracted researchers from different fields because of their high surface-to-volume ratio and other unique and remarkable properties. Cobalt and cobalt oxide nanoparticles (NPs) have various biomedical applications because of their distinctive antioxidant, antimicrobial, antifungal, anticancer, larvicidal, antileishmanial, anticholinergic, wound healing, and antidiabetic properties. In addition to biomedical applications, cobalt and cobalt oxide NPs have been widely used in lithium-ion batteries, pigments and dyes, electronic thin film, capacitors, gas sensors, heterogeneous catalysis, and for environmental remediation purposes. Different chemical and physical approaches have been used to synthesize cobalt and cobalt oxide NPs; however, these methods could be associated with eco-toxicity, cost-effectiveness, high energy, and time consumption. Recently, an eco-friendly, safe, easy, and simple method has been developed by researchers, which uses biotic resources such as plant extract, microorganisms, algae, and other biomolecules such as starch and gelatin. Such biogenic cobalt and cobalt oxide NPs offer more advantages over other physicochemically synthesized methods. In this review, we have summarized the recent literature for the understanding of green synthesis of cobalt and cobalt oxide NPs, their characterization, and various biomedical applications.
Adriamycin-resistant cells are significantly less fit than adriamycin-sensitive cells in cervical cancer
Authors: Qi Min , Xie Lijuan , Duan Guihua
Published: January 2021

Adriamycin (ADR) is an important chemotherapy agent in many advanced cancers, but the emergence of drug resistance during treatment is a major limitation to its successful use. Recent studies have suggested that drug-resistant cells become less fit and their growth could be inhibited by parental cells without cytotoxic treatment. In this study, we examined the fitness differences between HeLa and HeLa/ADR cells. Compared with the parental cell line, HeLa/ADR cells showed significantly lower growth rates, both in vitro and in vivo. There was no difference in the apoptosis rate between them, but G1 arrest and reduced DNA synthesis were found in HeLa/ADR cells. Further study indicated that HeLa/ADR cells failed to compete for space and nutrition against parental cells in vivo. Taken together, we demonstrate that HeLa/ADR cells are less fit and their growth can be inhibited by parental cells in the absence of ADR; therefore, the maintenance of a certain amount of ADR-sensitive cells during treatment may facilitate the control of the development of ADR resistance.
Effects of inorganic and organic selenium sources on the growth performance of broilers in China: A meta-analysis
Authors: Wei Chunbo , Lin Xiuwei , Zhang Ying , Wan Xuanchen , Wu Haotong , He Tao , Bi Kai , Wang Changping
Published: January 2021

This study aims to investigate the effects of different selenium (Se) sources on the growth performance of Chinese broilers and provide a scientific rationale for adding Se additives to broiler feed. Relevant studies that meet standard inclusion criteria were identified and extracted from China National Knowledge Infrastructure and Wanfang and Chinese Scientific Journal (VIP) databases. A total of 9 studies with 539 subjects were included. A meta-analysis was performed with STATA15.0 to estimate the combined standardized mean difference (SMD) with a 95% confidence interval (95% CI). Heterogeneity test of articles was examined by Q-test, and the results showed that P values of feed conversion ratio, average daily gain (ADG), and average daily intake were all less than 0.05, suggesting a strong heterogeneity among the selected literature. Therefore, the random effect model is selected to calculate the SMD of the three indexes. The combined SMDs (95% CI) of feed:gain, ADG, and average daily feed intake (ADFI) were −0.39 (−1.03, 0.25), 0.26 (−0.29, 0.81), and −1.45 (−3.09, 0.20), respectively, and the P values were all less than 0.05. This study shows that the absolute differences in the growth performance (feed:gain, ADG, and ADFI) of broilers fed with either organic or inorganic Se supplements at the same dose were quite small. The P values of Egger’s test were 0.770, 0.089, and 0.426, respectively, for the above indexes, showing no significant publication bias. Sensitivity analysis ensured the stability and reliability of the results. In summary, the effects of organic and inorganic Se in feed on the growth performance of broilers are statistically equal.
Prorenin and active renin levels in paediatrics: a bioanalytical review
Authors: Burdman Ilja , Burckhardt Bjoern B.
Published: January 2021

As part of the extended renin-angiotensin-aldosterone system, active renin and its precursor prorenin have been an area of research interest for decades. Although several studies showed a correlation with disease, other studies found no significant association, e.g. attributed to limited sample size or pharmacological effects of antihypertensive drugs. Since the measurement of both proteins has typically been carried out in adult populations, the data in paediatrics is limited. This review aimed to collate the current data on plasma renin and prorenin levels in children and compare the levels of healthy vs. the diseased state. A literature search using Medline resulted in 213 publications of which 15 studies were classified as relevant. In the extant studies in the literature, an age-dependent decline of renin plasma concentration was observed in newborns compared to adolescents. For children with cardiovascular disease, five studies were identified that provide limited insight into the pathophysiological regulation of renin. In general, sample handling is still a crucial step, which might particularly affect measured active renin concentrations due to conformational changes of its precursor prorenin. A reliable assessment for prorenin levels in the maturating population is yet not possible due to the low number of available publications. Three different approaches to quantify prorenin were found and raise the question on the comparability of these methods. The review emphazised several weaknesses and highlights the need for an accurate procedure to determine levels of active renin as well as prorenin in its closed and open form.
Comparative study of i-SENS glucometers in neonates using capillary blood samples
Authors: Kim Ha Nui , Yoon Soo-Young
Published: January 2021

Objectives

The accuracy of point-of-care blood glucometers in the detection and evaluation of neonatal hypoglycemia is a concern. This study compared the performance of three i-SENS glucometers with that of the YSI 2300 STAT Plus Analyzer, which was used as a reference.

Methods

The leftover neonatal capillary blood samples of 319 patients were used in this study. The evaluation process and accuracy performance criteria were based on the International Organization for Standardization 15197:2013 guidelines. The evaluation involved three i-SENS glucometers (BAROzen H Expert plus, CareSens PRO, and CareSens H Beat) and the ACCU-CHEK® Inform II glucometer.

Results

The accuracy evaluation yielded acceptable results as follows: a) 100 and 100% for BAROzen H Expert plus; 99.8 and 100% for CareSens PRO; 98.7%, and 97.2% for CareSens H Beat glucometers were within the range of ±0.8 mmol/L (15 mg/dL) and ±15% of the average reference values at glucose concentrations <5.55 mmol/L (100 mg/dL) and ≥5.55 mmol/L (100 mg/dL), respectively, and b) all estimated glucose values (100%) were within the zones A and B of Consensus Error Grid for all three i-SENS glucometers. There was good correlation between the glucose values estimated by the glucometers and the reference values (R>0.990).

Conclusions

This study demonstrated that i-SENS glucometers exhibit acceptable performance and can be used as effective point-of-care devices in neonates.
Evaluation of dried blood spots as alternative sampling material for serological detection of anti-SARS-CoV-2 antibodies using established ELISAs
Authors: Weisser Heike , Steinhagen Katja , Höcker Ralf , Borchardt-Lohölter Viola , Anvari Özlem , Kern Peter M.
Published: January 2021

Objectives

During the current pandemic, antibody testing based on venous serum helps to determine whether the tested person has been previously infected with SARS-CoV-2. Alternatively, capillary blood can be taken via a finger prick (dried blood spots, DBS). In this study, paired DBS and venipuncture samples were tested using two serological assays to evaluate the usability of DBS for the detection of anti-SARS-CoV-2 antibodies.

Methods

Paired samples of DBS and venous serum were collected from 389 volunteers, of whom 75 had a recent PCR-confirmed SARS-CoV-2 infection, and tested for anti-SARS-CoV-2 IgG antibodies against both viral S1 and nucleocapsid protein (NCP) antigens using two ELISAs. Degree of agreement and correlation coefficients between ELISA results based on the two sampling methods were calculated.

Results

Results of DBS showed almost perfect agreement and high correlations with results from corresponding serum samples in both the S1-based ELISA and the NCP-based ELISA.

Conclusions

ELISA results derived from DBS showed very high agreement to those obtained with serum, supposing adequate usability and robustness of DBS as sample material for detection of anti-SARS-CoV-2 antibodies. In the near future, large-scale epidemiological screening for antibodies against SARS-CoV-2 will be carried out. Since DBS reduce the strain on healthcare institutions regarding sample collection, they have a potential to facilitate efficient community- and population-based screening in the current SARS-CoV-2 pandemic.
The underestimated issue of non-reproducible cardiac troponin I and T results: case series and systematic review of the literature
Authors: Favresse Julien , Bayart Jean-Louis , Gruson Damien , Bernardini Sergio , Clerico Aldo , Perrone Marco
Published: January 2021

Cardiac troponins (cTn) are the preferred biomarkers for the evaluation of myocardial injury and play a key role in the diagnosis of acute myocardial infarction (MI). Pre-analytical or analytical issues and interferences affecting troponin T and I assays are therefore of major concern given the risk of misdiagnosis. False positive troponin results have been related to various interferences including anti-troponin antibodies, heterophilic antibodies, or elevated alkaline phosphatase level. On the other hand, false negative results have been reported in the case of a large biotin intake. These interferences are characterized with erroneous but reproducible troponin results. Of interest, non-reproducible results have also been reported in the literature. In other words, if the sample is reanalyzed a second time, a significant difference in troponin results will be observed. These interferences have been named “fliers” or “outliers”. Compared to the biotin interference that received major attention in the literature, troponin outliers are also able to induce harmful clinical consequences for the patient. Moreover, the prevalence of outliers in recent studies was found to be higher (0.28–0.57%) compared to the biotin interference. The aim of this systematic review is to warn clinicians about these non-reproducible results that may alter their clinical judgment. Four case reports that occurred in the Clinique of Saint-Luc Bouge are presented to attest this point. Moreover, we aimed at identifying the nature of these non-reproducible troponin results, determining their occurrence, and describing the best way for their identification.
Vitamin-D levels and intensive care unit outcomes of a cohort of critically ill COVID-19 patients
Authors: Orchard Laurence , Baldry Matthew , Nasim-Mohi Myra , Monck Chantelle , Saeed Kordo , Grocott Michael P. W. , Ahilanandan Dushianthan
Published: January 2021

Objectives

The pattern of global COVID-19 has caused many to propose a possible link between susceptibility, severity and vitamin-D levels. Vitamin-D has known immune modulatory effects and deficiency has been linked to increased severity of viral infections.

Methods

We evaluated patients admitted with confirmed SARS-COV-2 to our hospital between March-June 2020. Demographics and outcomes were assessed for those admitted to the intensive care unit (ICU) with normal (>50 nmol/L) and low (<50 nmol/L) vitamin-D.

Results

There were 646 SARS-COV-2 PCR positive hospitalisations and 165 (25.5%) had plasma vitamin-D levels. Fifty patients were admitted to ICU. There was no difference in vitamin-D levels of those hospitalised (34, IQR 18.5–66 nmol/L) and those admitted to the ICU (31.5, IQR 21–42 nmol/L). Higher proportion of vitamin-D deficiency (<50 nmol/L) noted in the ICU group (82.0 vs. 65.2%). Among the ICU patients, low vitamin D level (<50 nmol/L) was associated with younger age (57 vs. 67 years, p=0.04) and lower cycle threshold (CT) real time polymerase chain reaction values (RT-PCR) (26.96 vs. 33.6, p=0.02) analogous to higher viral loads. However, there were no significant differences in ICU clinical outcomes (invasive and non-invasive mechanical ventilation, acute kidney injury and mechanical ventilation and hospital days) between patients with low and normal vitamin-D levels.

Conclusions

Despite the association of low vitamin-D levels with low CT values, there is no difference in clinical outcomes in this small cohort of critically ill COVID-19 patients. The complex relationship between vitamin-D levels and COVID-19 infection needs further exploration with large scale randomized controlled trials.
Serum N-glycan fingerprint nomogram predicts liver fibrosis: a multicenter study
Authors: Huang Chenjun , Liu Lijuan , Wang Hao , Fang Meng , Feng Huijuan , Li Ya , Wang Mengmeng , Tong Lin , Xiao Xiao , Wang Ziyi , Xu Xuewen , He Yutong , Gao Chunfang
Published: January 2021

Objectives

Liver cirrhosis (LC) is the end-stage of fibrosis in chronic liver diseases, non-invasive early detection of liver fibrosis (LF) is particularly essential for therapeutic decision. Aberrant glycosylation of glycoproteins has been demonstrated to be closely related to liver abnormalities.

Methods

This study was designed to enroll a total of 1,565 participants with LC/LF, chronic hepatitis virus (CHB) and healthy controls. Fibrosis was confirmed by liver biopsy. Using capillary electrophoresis N-glycan fingerprint (NGFP) analysis, we developed a nomogram algorithm (FIB-G) to discriminate LC from non-cirrhotic subjects.

Results

The FIB-G demonstrated good diagnostic performances in identifying LC with the area under the curve (AUC) 0.895 (95%CI: 0.857–0.915). Furthermore, the diagnostic efficiencies of FIB-G were superior to that of log (P2/P8), procollagen III N-terminal (PIIINP), type IV collage (IV-C), laminin (LN), hyaluronic acid (HA), aspartate transaminase to platelets ratio index (APRI), and FIB-4 when detecting significant fibrosis (S0–1 vs. S2–4, AUC: 0.787, 95%CI: 0.701–0.873), severe fibrosis (S0–2 vs. S3–4, AUC: 0.844, 95%CI: 0.763–0.924), and LC (S0–3 vs. S4, AUC: 0.773, 95%CI: 0.667–0.880). Besides, changes of FIB-G were associated well with the regression of fibrosis and liver function Child–Pugh classification.

Conclusions

FIB-G is an accurate multivariant N-glycomic algorithm for LC prediction and fibrosis progression/regression monitoring. The high throughput feasible NGFP using only 2 μL of serum could help physicians make the more precise non-invasive staging of LF or cirrhosis and reduce the need for invasive liver biopsy.
Mechanism of bilirubin elimination in urine: insights and prospects for neonatal jaundice
Authors: Thomas Mercy , Hardikar Winita , Greaves Ronda F. , Tingay David G. , Loh Tze Ping , Ignjatovic Vera , Newall Fiona , Rajapaksa Anushi E.
Published: January 2021

Despite a century of research, bilirubin metabolism and the transport mechanisms responsible for homeostasis of bilirubin in serum remain controversial. Emerging evidence on the hepatic membrane transporters and inherited disorders of bilirubin metabolism have contributed to a greater understanding of the various steps involved in bilirubin homeostasis and its associated excretory pathways. We discuss these recent research findings on hepatic membrane transporters and evaluate their significance on the newborn bilirubin metabolism and excretion. New insights gained speculate that a proportion of conjugated bilirubin is excreted via the renal system, as an alternative to the intestinal excretion, even in normal physiological jaundice with no associated pathological concerns. Finally, this paper discusses the clinical relevance of targeting the altered renal excretory pathway, as bilirubin in urine may hold diagnostic importance in screening for neonatal jaundice.
How to meet ISO15189:2012 pre-analytical requirements in clinical laboratories? A consensus document by the EFLM WG-PRE
Authors: Vermeersch Pieter , Frans Glynis , von Meyer Alexander , Costelloe Seán , Lippi Giuseppe , Simundic Ana-Maria
Published: January 2021

The International Organization for Standardization (ISO) 15189:2012 standard aims to improve quality in medical laboratories through standardization of all key elements in the total testing process, including the pre-analytical phase. It is hence essential that accreditation bodies, assessing laboratories against ISO15189:2012, pay sufficient attention to auditing pre-analytical activities. However, there are significant differences in how technical auditors interpret the pre-analytical requirements described in ISO15189:2012. In this consensus document, the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) Working Group for Pre-analytical Phase (WG-PRE) sets out to review pre-analytical requirements contained in ISO15189:2012 and provide guidance for laboratories on how to meet these requirements. The target audience for this consensus document is laboratory professionals who wish to improve the quality of the pre-analytical phase in their laboratory. For each of the ISO requirements described in ISO15189:2012, members of EFLM WG-PRE agreed by consensus on minimal recommendations and best-in-class solutions. The minimal consensus recommendation was defined as the minimal specification which laboratories should implement in their quality management system to adequately address the pre-analytical requirement described in ISO15189:2012. The best-in-class solution describes the current state-of-the-art in fulfilling a particular pre-analytical requirement in ISO15189:2012. We fully acknowledge that not every laboratory has the means to implement these best-in-class solutions, but we hope to challenge laboratories in critically evaluating and improving their current procedures by providing this expanded guidance.
Artificial Intelligence and Machine Learning
Authors: Lawlor Bonnie
Published: January 2021

The uses of Artificial Intelligence (AI) and Machine Learning (ML) are topics of presentations at most conferences today across diverse professional disciplines. Why? The following quote says it all:
Chinese does have independent tense elements
Authors: Zhang Zhiyi , Shikun Li
Published: January 2021

Previous research on Chinese tense indicates that Chinese has either null tense or no tense. However, the present study suggests that the conclusions of previous studies regarding Chinese tense are either against the syntactic truth or illogical. The present study provides new evidence to support that Chinese has two independent tense elements,zaiandguo, which clearly indicate present and past tense, contrary to the traditional assumption that they are aspectual markers. From the perspective of grammaticalization, bothzaiandguowitnessed grammaticalization from the spatial concept to the temporal concept. The semantic evidence shows thatzaiandguoare semantically different from the aspectual markerszheandleand convey the meaning of time location. The fact that bothzaiandguoare allowed in negation but not permitted in non-finite structure provides syntactic evidence that they are tense markers. However, the present study also suggests there can be two differentzaiandguo;zaiandguoused separately and independently andzaiandguoused withzheandle.In the latter case,zaiis a time adverbial andguois an aspectual marker. The existence of independent tense markers in Chinese also shows that Chinese may have at least four different mechanisms to anchor tense.
A multimodal analysis of Jane Eyre book covers
Authors: Wu Jie , Wu Qinghong
Published: January 2021

This paper applies visual grammar theory to make a multimodal discourse analysis of book covers of the different Chinese versions of Jane Eyre. It illustrates the relationship between the social environment and social changes in Chinese society and culture in relation to an increasing social acceptance of the novel in China. This research not only validates the applicability and practicability of visual grammar in analyzing book covers, but also helps to show an ideological change in Chinese readers and publishers over time from the 1930s to the 21st century. Indeed, the connotations of book covers of the different Chinese versions of Jane Eyre seem to be closely related to different historical and social contexts. They document and bear witness to, in their particular way, the tremendous changes in Chinese society from early last century on. They also show that Jane, the heroine of the novel, seemed to be re-discovered over and over again in China, depending on the main social features of different periods. She seems to have been portrayed as the gray presence, the feminist, the lover and protagonist, and finally the icon.
Double consciousness to scaffold narrative skills
Authors: West Donna E.
Published: January 2021

Determining the utility of auditory hallucinations (including imaginary friends) in developing logic is sorely under-investigated (Fernyhough, Charles. 2016. The voices within: The history and science of how we talk to ourselves. New York: Basic Books). The present account demonstrates how Peirce’s double consciousness fueled by his endoporeutic principle, provides insight into how abduction directs adopting arguments from one source while dismissing others. Peirce’s categories provide hints as to which voices become admitted to logical scrutiny, and which are validated – consequent to irritations imposed by surprise/conflict. Effort/resistance (4.536) clearly illustrates how Secondness legitimizes emerging perspectives, facilitating examination of peripheral voices, which can be competitive (MS 9) or collaborative (4.551). Peirce’s Energetic and Emotional Interpretants (MS 318) impel or inhibit new habits (attention to one stimulus over another). Consciously inhibiting forces hastens self-control (Thirdness) integrating voices on the fringes of conventionality into one’s own (MS 318). Ultimately, incorporating alterity via imagined arguments satisfies Peirce’s endoporeutic maxim because reflecting upon the legitimacy of alien perspectives transforms habits from the outside in.
Peirce on learning and teaching
Authors: Nöth Winfried
Published: January 2021

The paper is a precis of C. S. Peirce’s semiotic theory of education. It presents this theory of learning and teaching from the perspective of Peirce’s phenomenological categories of Firstness, Secondness, and Thirdness. In the domain of Thirdness, learning is mediation between ignorance and knowledge, new information and old knowledge. Teaching has its focus on laws, symbols, legisigns, and reasoning. In the domain of Secondness, learners acquire new knowledge from the “hard realities” of real-life experience, from obstacles, and from the resistance caused by error and doubt. Teaching takes place by means of sinsigns (singular signs) and indexical signs. In the domain of Firstness, the learner acquires familiarity with the sensory qualities of objects of experience and learns from free associations, imagination, and acts of creativity. The instruments of teaching are qualisigns, icons, and abductive reasoning. The paper concludes that Peirce’s philosophy of education is holistic insofar as it states that most efficient signs are those signs in which “the iconic, indicative, and symbolic characters are blended as equally as possible.”
Peircean anti-psychologism and learning theory
Authors: Campbell Cary , Olteanu Alin , Feil Sebastian
Published: January 2021

Taking influence from Peirce’s phenomenological categories (Firstness, Secondness, Thirdness), a notion of what we callbottom-up modelinghas become increasingly significant in research areas interested in learning, cognition, and development. Here, following a particular reading of Peircean semiotics (cf. Deacon, Terrence. 1997.The symbolic species: The co-evolution of language and the brain. London and New York: W. W. Norton; Sebeok, Thomas and Marcel Danesi. 2000.The forms of meaning: Modelling systems theory and semiotic analysis. Berlin and New York: Mouton de Gruyter), modeling, and thus also learning, has mostly been thought of as ascending from simple, basic sign types to complex ones (iconic – indexical – symbolic; Firstness – Secondness – Thirdness). This constitutes the basis of most currently accepted (neo-Peircean) semiotic modeling theories and entails the further acceptance of an unexamined a priori coherence between complexity of cognition and complexity of signification. Following recent readings of Peirce’s post-1900 semiotic, we will present, in abbreviated form, a discussion as to the limits of this theoretical approach for theories of learning that draws upon Peirce’s late semiotic philosophy, in particular his late work on iconicity and propositions. We also explore the corollary conceptions of semioticresourcesandcompetencesandaffordancesto develop an ecological perspective on learning that notably does not impose a linear developmental progression from simple to complex. In conclusion, we address some of the implications of this (post-Peircean) conceptualization for transdisciplinary research into learning.
Learning from tragedy – The Jessica Barnett story: challenges in the diagnosis of long QT syndrome
Authors: Graber Mark L. , Olson Andrew P. J. , Barnett Tanya
Published: January 2021

We describe the case of Jessica Barnett, an adolescent girl whose repeated episodes of syncope and near-syncope were ascribed to a seizure or anxiety disorder. The correct diagnoses (congenital long QT syndrome; arrythmogenic right ventricular cardiomyopathy) were established by autopsy and genetic studies only after her death at age 17. The perspective of the family is presented, along with an analysis of what went right and what went wrong in Jessica’s diagnostic journey. Key lessons in this case include the value of family as engaged members of the diagnostic team, that a ‘hyperventilation test’ should not be used to exclude cardiac origins of syncope or pre-syncope, and the inherent challenges in the diagnosis of the long QT syndrome.
Formulation and optimization of gastroretentive bilayer tablets of calcium carbonate using D-optimal mixture design
Authors: Moganti Manasa , Nanjappa Shivakumar H.
Published: January 2021

Gastroretentive bilayer tablets of calcium carbonate (CC) were developed using D-optimal mixture design. The effect of formulation factors such as levels of HPMC K100 M (X1), sodium bicarbonate (X2), and HPMC E15 LV (X3) on responses like floating lag time (R1) and release of CC at 1 h (R2) and 6 h (R3) was elucidated. The optimized formulations developed by numerical optimization technique were found to have short floating lag time (2.85 ± 0.98 min), minimum burst release (27.02 ± 1.18%), and controlled yet near complete release (88.98 ± 2.75%) at 6 h. In vivo radiographic studies in rabbits indicated that optimized batch displayed a mean gastric retention time (GRT) of 5.5 ± 1 h which was significantly prolonged (P < 0.05) compared to the conventional tablets that displayed a GRT of less than 1 h. The studies proved that the gastroretentive tablets can be a promising platform to improve bioavailability of nutrients having absorption window in upper gastrointestinal tract.
Evaluation of physicochemical properties of film-based alginate for food packing applications
Authors: Azucena Castro-Yobal María , Contreras-Oliva Adriana , Saucedo-Rivalcoba Veronica , Rivera-Armenta José Luis , Hernández-Ramírez Gabriela , Salinas-Ruiz Josafhat , Herrera-Corredor Andrés
Published: January 2021

The indiscriminate use of films as synthetic primary packaging, for the conservation and transport of fruit and vegetable products in postharvest, causes disposal problems. In the present work, films based on sodium alginate were synthesized and characterized, with alginate as a biopolymer matrix, glycerol (plasticizer), oleic acid (control of hydrophilicity), and calcium chloride (cross-linking agent). The dynamic mechanical, thermal, structural, and hydrophobicity properties were studied. In the case of dynamic mechanical properties, they were analyzed at a temperature of −50°C, because food packaging goes through storage during its cold chain, showing biofilm stability under these conditions. On the other hand, infrared spectroscopy analysis showed that the carboxylate and carboxy functional groups serve as a link for all the components, and oleic acid is also serving as a plasticizer and, to a lesser degree, as a hydrophilicity controller.
Hedging the Risk of Wind Power Production Using Dispatchable Energy Source
Authors: D’Amico Guglielmo , Di Basilio Bice , Petroni Filippo
Published: January 2021

In this paper we advance a nonlinear optimization problem for hedging wind power variability by using a dispatchable energy source (DES) like gas. The model considers several important aspects such as modeling of wind power production, electricity price, nonlinear penalization scheme for energy underproduction and interrelations among the considered variables. Results are given in terms of optimal co-generation policy with DES. The optimal policy is interpreted and analyzed in different penalization scenarios and related to a 48 MW hypothetical wind park. The model is suitable for integration of wind energy especially for isolated grids. Some probabilistic results for special moments of a Log-Normal distribution are obtained; they are necessary for the evolution of the optimal policy.
Generalized fractal dimensions of invariant measures of full-shift systems over compact and perfect spaces: generic behavior
Authors: Carvalho Silas L. , Condori Alexander
Published: January 2021

In this paper, we show that, for topological dynamical systems with a dense set (in the weak topology) of periodic measures, a typical (in Baire’s sense) invariant measure has, for each

q
>
0

{q>0}

, zero lower q-generalized fractal dimension.
This implies, in particular, that a typical invariant measure has zero upper Hausdorff dimension and zero lower rate of recurrence.
Of special interest is the full-shift system

(
X
,
T
)

{(X,T)}

(where

X
=

M
ℤ

{X=M^{\mathbb{Z}}}

is endowed with a sub-exponential metric and the alphabet M is a compact and perfect metric space), for which we show that a typical invariant measure has, for each

q
>
1

{q>1}

, infinite upper q-correlation dimension.
Under the same conditions, we show that a typical invariant measure has, for each

s
∈

(
0
,
1
)

{s\in(0,1)}

and each

q
>
1

{q>1}

, zero lower s-generalized and infinite upper q-generalized dimensions.