bluuebunny/crossref_metadata_2025_split huggingface dataset:
Boundedness and almost periodicity of solutions of linear differential systems
Authors: Lassoued Dhaou , Fečkan Michal 
Published: December 2022

Abstract
In this paper, we study the following linear differential system

(1)

x
′

(
t
)
=
A
(
t
)
x
(
t
)
,

x
(
t
)
∈

ℝ
n

,

t
∈
ℝ
,

$${{x}^{\prime }}(t)=A(t)x(t),\,\,\,\,x(t)\in {{\mathbb{R}}^{n}},\quad t\in \mathbb{R},$$

where t ↦ A(t) is a matrix valued almost periodic function. We prove that if all the solutions of the above system are almost periodic, there exists an almost periodic function b : R → R
n
such that the following differential equation

(2)

x
′

(
t
)
=
A
(
t
)
x
(
t
)
+
b
(
t
)
,

x
(
t
)
∈

ℝ
n

,

t
∈
ℝ

$${{x}^{\prime }}(t)=A(t)x(t)+b(t),\,\,\,\,x(t)\in {{\mathbb{R}}^{n}},\quad t\in \mathbb{R}$$

has no bounded solution.
In particular, if for each almost periodic function b there exists a bounded solution to (2), there exists at least one solution for (1) that is not almost periodic.
On variational approaches for fractional differential equations
Authors: Salari Amjad , Biranvand Nader , Hashemi Sababe Saeed 
Published: December 2022

Abstract
This paper deals with the existence and numerical estimates of solutions for a class of fractional differential equations, while the nonlinear part of the problem admits some Special hypotheses. In particular, for a precise localization of the parameter, the existence of a non-zero solution is established requiring the sublinearity of nonlinear part at origin and infinity. Moreover, theoretical and numerical examples of applications are provided.
Approximation theorems for the new construction of Balázs operators and its applications
Authors: Usta Fuat 
Published: December 2022

Abstract
Balázs operators are an influential tool that can be used to approximate a function on the unbounded interval [0, ∞). In this study, a new construction of Balázs operators which depending upon on a function ρ(x) has been introduced. The function ρ(x) plays a significant role in this construction due to the fact that the new operator preserves definitely two test functions from the set of {1, ρ(x), ρ
2(x)}. In this direction, the approximation properties of this newly defined operators are established, such as degree of approximation and Voronovskaya type theorems. Finally, we presented a set of computational examples in order to validate the new construction of operator is an approximation procedure.
A new family of compound exponentiated logarithmic distributions with applications to lifetime data
Authors: Hakamipour Nooshin , Zhang Yuanyuan , Nadarajah Saralees 
Published: December 2022

Abstract
The logarithmic distribution and a given lifetime distribution are compounded to construct a new family of lifetime distributions. The compounding is performed with respect to maxima. Expressions are derived for lifetime properties like moments and the behavior of extreme values. Estimation procedures for the method of maximum likelihood are also derived and their performance assessed by a simulation study. Three real data (including two lifetime data) applications are described that show superior performance (assessed with respect to Kolmogorov Smirnov statistics, likelihood values, AIC values, BIC values, probability-probability plots and density plots) versus at least five known lifetime models, with each model having the same number of parameters as the model it is compared to.
On two correlated linear models with common and different parameters
Authors: Jiang Bo , Liu Ming , Tian Yongge 
Published: December 2022

Abstract
A parametric regression model may comprise several correlated individual regression equations, and these equations may have common and different unknown parameters. In such a situation, the common unknown parameter vectors in these equations can be estimated individually or simultaneously according to various available statistical inference methods. The purpose of this paper is to provide an integral account of two classic objects in regression theory: the best linear unbiased predictors (BLUPs) and the best linear unbiased estimators (BLUEs) on common and different unknown parameters in two correlated linear models with common and different parameters. We first introduce some reduced models associated with the two correlated linear models. We then define and characterize predictability and estimability of all unknown parameter vectors in the two correlated models and their reduced models, and derive analytical formulas for calculating the BLUPs and BLUEs of all unknown parameter vectors in these models by means of a constrained quadratic matrix optimization method. We also discuss a variety of theoretical properties of the predictors and estimators.
Ideals of functions with compact support in the integer-valued case
Authors: Dube Themba , Ighedo Oghenetega , Tlharesakgosi Batsile 
Published: December 2022

Abstract
For a zero-dimensional Hausdorff space X, denote, as usual, by C(X, ℤ) the ring of continuous integer-valued functions on X. If f ∈ C(X, ℤ), denote by Z(f) the set of all points of X that are mapped to 0 by f. The set

$$\begin{array}{}
\displaystyle
C_K(X,\mathbb Z)=\{f\in C(X,\mathbb Z)\mid \text{cl}_X(X\smallsetminus
\mathsf Z(f))\text{ is compact}\}
\end{array}$$

is the integer-valued analogue of the ideal of functions with compact support in C(X). By first working in the category of locales and then interpreting the results in spaces, we characterize this ideal in several ways. Writing ζ
X for the Banaschewski compactification of X, we also explore some properties of ideals of C(X, ℤ) associated with subspaces of ζ
X analogously to how one associates, for any Tychonoff space Y, subsets of β
Y with ideals of C(Y).
Triangular numbers and generalized fibonacci polynomial
Authors: Şahіn Adem 
Published: December 2022

AbstractIn the present paper, we study triangular numbers. We focus on the linear homogeneous recurrence relation of degree 3 with constant coefficients for triangular numbers. Then we deal with the relationship between generalized Fibonacci polynomials and triangular numbers. We show that different properties of triangular numbers can be obtained by using this relationship. Finally, we examine the properties of the sequenceA052529 that has strong relationships with triangular numbers.
Enveloping action: Convergence spaces
Authors: Losert Bernd , Richardson Gary 
Published: December 2022

Abstract
Given a partial action, an enveloping action in the context of convergence spaces is studied. Whenever the enveloping action space is not Hausdorff (T
3), a related enveloping action on a Hausdorff (T
3) space is developed. Invariance of quotient (proper, open) maps to the related space is also discussed.
Effects of rare earth metals on microstructure, mechanical properties, and pitting corrosion of 27% Cr hyper duplex stainless steel
Authors: Wang Hang , Wang Aiqin , Li Changyi , Yu Xingsheng , Xie Jingpei , Liang Tingting , Liu Chenlu 
Published: December 2022

Abstract
This research focuses on the addition of low-cost rare earth metals (REMs) to improve the comprehensive properties of hyper duplex stainless steels (DSSs). The effects of REM on the microstructure, mechanical properties, and pitting corrosion of hyper DSSs were analyzed by optical/scanning electron microscope metallographic examination, X-ray diffraction analysis, tensile test, impact test, and potentiodynamic polarization test. With the addition of REM, micro/nanoscale REM inclusions were formed, and the microstructure of the alloy was refined. With the increasing content of REM, the average diameter and area of inclusions in the alloy decreased at first and then increased. While the mechanical properties showed a trend of first increasing and then decreasing. An appropriate amount of stable REM inclusions could reduce the susceptibility of pitting corrosion and improve the pitting corrosion resistance of the alloy. The hyper DSSs with REM content in the range of 0.018–0.031 wt% have excellent mechanical properties and pitting resistance.
A case of unilateral post-COVID-19 adrenal haemorrhage and follow-up during pregnancies
Authors: Mangone Alessandra , Yousuf Quratulain , Arlt Wiebke , Prete Alessandro , Shaheen Fozia , Krishnasamy Senthil-kumar , Elhassan Yasir S , Ronchi Cristina L 
Published: December 2022

Summary
The spectrum of endocrine-related complications of COVID-19 infection is expanding; one of the most concerning of which is adrenal haemorrhage due to the risk of catastrophic adrenal crisis. In this study, we present a case that highlights the challenging management of a large, indeterminate unilateral adrenal mass during pregnancy and draws attention to a rare yet probably underestimated complication of COVID-19. During hospitalization for severe COVID-19 pneumonia, a 26-year-old woman was incidentally found to have a 12.5 cm heterogeneous left adrenal mass. Soon after the discovery, she became pregnant and upon referral, she was in the seventh week of gestation, without clinical or biochemical features of hormonal excess. The uncertainty of the diagnosis and the risks of malignancy and surgical intervention were discussed with the patient, and a period of radiological surveillance was agreed upon. An MRI scan performed 3 months later showed a size reduction of the adrenal lesion to 7.9 cm, which was against malignancy. A Doppler ultrasound showed a non-vascular, well-defined round lesion consistent with an adrenal haematoma, likely a complication of the recent COVID-19 infection. The multidisciplinary team recommended further radiological follow-up. The patient then spontaneously had miscarriage at 12 weeks gestation. Subsequent radiological surveillance showed a further size reduction of the adrenal lesion to 5.5 cm. The patient conceived again during follow-up, and the repeated Doppler ultrasound showed stable appearances of the adrenal mass, and thus, it was agreed to continue radiological monitoring after delivery. The pregnancy was uneventful, and the patient delivered a healthy baby. An MRI scan performed after delivery showed a stable but persistent lesion consistent with a likely underlying adrenal lesion.

Learning points

Unilateral adrenal haemorrhage can occur as a complication of COVID-19 and should be considered in the differential diagnosis of heterogeneous adrenal masses if there is a history of recent infection.

Management of large indeterminate adrenal masses during pregnancy poses several challenges and should be led by an experienced multidisciplinary team.

Underlying adrenal tumours may trigger non-traumatic haemorrhages, especially if exacerbated by stressful illness.
Specifics of vitrification of in vitro-produced cattle embyos at various development stages
Authors: Kovpak V. V. , Kovpak O. S. , Valchuk O. A. , Zhuk Y. V. , Derkach S. S. 
Published: December 2022

Producing embryos in vitro is an important technology used to improve the genetic potential of cattle and perfect the programs of their breeding. Regardless of the way they are produced, all embryos that had not been used for transplantation to recipients must be conserved. Because of significantly increased interest in the problem of cryoconservation of embryos, both coming from scientists and businesses, there are emerging new commercial environments that allow the facilitation of cryoconservation and the increase in the embryo survival. Oocyte-cumulus complexes obtained from the ovaries of slaughtered clinically healthy cows matured in 22–24 h in in vitro conditions. The oocytes were co-cultured with spermatozoids in Fertilization medium, and the obtained zygotes were cultured in Culture medium with Sodium-Pyruvate for 4 or 7 days up to the stage of morula or blastocyste, respectively. For the vitrification of cow embryos, we used a commercial kit for the vitrification of human embryos, having compared the duration of equilibration. According to the results of the studies, we observed high efficiency of cryoconservation of cow embryos using the commercial kit for vitrification of human embryos. The results revealed the significant effect of equilibration on survival and further development of embryos. In addition, we described the dependence of development stage of cattle embryo on the duration of the contact of embryo with equilibration solution. Therefore, optimal time of contact of cattle embryos at the morula stage with equilibration solution was 12 minutes. On the 24th h after thawing, 46.7 ± 3.3% of the embryos were observed to undergo blastulation, and on 48th h, this parameter increased to 96.7 ± 3.3%, which corresponded to the parameters in the group of embryos that had not been subjected to cryoconservation. In the conditions of further cultivation, the percentage of blastocystes that hatched in the experimental group was no different from that of the control. At the same time, the highest efficiency of vitrification of blastocystes of cows was seen after the contact with the equilibration solution for 15 min, since the percentage of hatched blastocystes was the same as in the control group. Therefore, using the commercial kit for vitrification of human embryos is beneficial, for it promotes the parameters of cow embryos after vitrification/thawing that are similar to such of intact embryos (without freezing). The data we analyzed and presented in the paper could help to increase the efficiency of cryoconservation of cattle embryos for both scientific and commercial purposes.
The impact of parameter estimation uncertainty in extreme wind speed models
Authors: Kenéz Ágnes , Joó Attila László 
Published: December 2022

AbstractAll the available information and uncertainties should be taken into account in a model to give correct answer to a stated problem and evaluate the performance of a structure. This study deals with the impact of parameter estimation uncertainty in extreme wind speeds on the assessed reliability index using frequentist approach. The peak-over-threshold approach with an automated threshold selection method is applied and bootstrapping is used to determine the 95% confidence interval of the estimated reliability index. Based on the results practical recommendations, i.e., a framework of this procedure are derived on how to handle peak-over-threshold in extreme wind speed models for the application of the proposed performance-based wind engineering design.
Elimination of the main damage of the ventilation system of the boiler premise
Authors: Voznyak Orest , Kasynets Mariana , Spodyniuk Nadiia , Savchenko Olena , Sukholova Iryna , Dovbush Oleksandr 
Published: December 2022

AbstractThe article is devoted to solving of urgent problem: creation of staff work safety in the boiler room due to ensure of required conditions by natural ventilation. The aim of the work is to eliminate the main damage of the natural ventilation system of the boiler premise by using of compact air jet due to correction coefficients and updated results. Static and dynamic air pressure, difference of static pressure due to wind, aerodynamic coefficients and air balance for necessary nature ventilation of the boiler premise as well temperature correction coefficient are established. The update calculation dependencies for determining of the air static pressure and its volume flow rate in the boiler room have been obtained. Updated graph, monogram, and analytical equations for natural ventilation calculation of boiler room are presented.
Determinants of Successful Crowdfunding Campaigns: Evidence from Russian Crowdfunding Platform Boomstarter
Authors: Макарова Светлана Геннадьевна , Улитина Дарья Алексеевна 
Published: December 2022

According to practice, about half of the projects on crowdfunding sites (based on rewards) do not collect the declared amount of funding. This is largely due to the lack of experience in running crowdfunding campaigns and ignoring important factors that are important to take into account when managing crowdfunding campaigns. Many foreign publications have studied the nature of the influence of various determinants on the success of fundraising on crowdfunding platforms, in particular, on Kickstarter, Indiegogo, Ulule, Eppela and others. As for research on Russian crowdfunding platforms, there is an extremely small number of such studies. Based on the construction of OLS regressions for 300 projects from July 2020 to May 2022 by the end date of the project from the Russian crowdfunding platform Boomstarter, we firstly obtained that such determinants as choosing a reasonable financial goal of the project, the number of sponsors, the numberof project comments and the availability of video materials about the project have a positive impact on the success of the crowd campaign. In addition, we have developed a model based on logit regression testing, which has a high predictive power. This model can be used to predict the results of a crowd campaign with given parameters.
In further research in this area, it is possible to increase the number of observations, change the set of factors that potentially affect the success of a project’s fundraising on crowdfunding platforms, and also consider the influence of factors depending on the category of the project. A promising area of research is the analysis of social interactions between investors in the framework of crowdfunding campaigns and the identification of the nature of the dependence of the volume of collected financial resources throughout the entire project financing cycle in the Russian market.
Intuitive risk perception, anxiety and worry during the COVID-19 outbreak in Mexico
Authors: Salinas-Rivera Edgar , Velázquez-Jurado Héctor , Castro Carlos G. , Rico-López Juan Manuel 
Published: December 2022

Preventive behavior and decision-making processes depend greatly on risk perception. Incorporating the affective component in risk assessment provides valuable information for understanding COVID-19-related risk. The study aimed to adapt and validate the COVID-19 Risk Belief Scale and evaluating Intuitive Risk Perception and its association with anxiety and worry. A cross-sectional study was conducted analyzing data from 694 Mexican adults, which was collected through on-line platforms during 2020. The final CFA including 18 items showed adequate goodness-of-fit indices (RMSEA = 0.059, 90% CI [0.053, 0.065]; CFI = 0.95; TLI = 0.94; SRMR = 0.044) supporting a five-factor structure. Moderate levels of intuitive risk perception were found, as well as moderate to low levels of worry and somatic anxiety. Significant correlations between both measures and risk perception were observed. This study confirms the importance of the affective component within risk assessment and findings become highly significant considering the current worldwide pandemic conditions.
How might we apply the trinitarian notion of ‘Person’ to mere humans?
Authors: Patterson Colin 
Published: December 2022

The theological concept of ‘person’ and its complementary notion of ‘nature’ were developed through early church teaching on the Holy Trinity and the Incarnation. Persons in this case referred solely to the Father, Son and Holy Spirit while ‘nature’ expressed the unity of the Godhead and encompassed those attributes which were shared by the divine Persons. The later history of this theologically derived notion of ‘person’ took a different turn, moving away from the early complementarity of nature and person in order to embrace the notion of human person for which complementarity seemed ill fitting. In this new conception, ‘person’ was subsumed under the category of ‘nature’. A human person came to refer to the full human reality, body and soul, while a more general notion, aimed at accommodating both divine and human personhood, as famously expressed by Boethius, thought of a person as an individual substance of a rational nature.
One might ask, however, whether it is possible and fruitful to develop the initial, complementary concept of ‘person’ in a different direction, that is, so that it covers not only divine Persons but also mere humans. Does it give a coherence to the area of theological anthropology beyond that afforded by the classical, nature-based concept of ‘person’? Here I attempt to set out a conceptual framework for the application to humans of the concept of ‘person’ as it was developed with the theological controversies of the early Church – or at least according to one reading of that process. I first take note of the features of the theological notion of personhood and test whether human persons might be understood in the same or similar terms, taking into account the difference between divine and creaturely existence. I then draw comparisons with the traditional concept of ‘person’ as it has been applied to human beings to show that the former version is to be preferred. I conclude with comments which draw out some of the implications of this theological notion of person.
Katecheta we wspólnocie Kościoła świadkiem wiary i mistagogiem
Authors: Buchta Roman 
Published: December 2022

Ustanawiając posługę świecką katechety, papież Franciszek wyraził nadzieję, iż podobnie jak miało to miejsce w chrześcijańskiej starożytności, katecheta ze względu na powierzone mu zadania będzie zarazem świadkiem wiary, mistrzem i mistagogiem, towarzyszem i pedagogiem, który naucza w imieniu Kościoła. Celem naukowym artykułu jest wydobycie mistagogicznego wymiaru formacji katechetów przygotowujących się do podjęcia posługi we wspólnotach parafialnych oraz prezentacja związanych z nią kierunków działań duszpasterskich, prowadzonych w katowickim Kościele w ramach Archidiecezjalnego Centrum Formacji Pastoralnej. Główny problem badawczy wyraża się w pytaniu o charakter formacji katechetów posługujących we wspólnotach parafialnych oraz ich szczególne kompetencje. Dla opracowania problemu posłużono się metodami analizy i syntezy. Analiza dokumentów katechetycznych, przeprowadzona w świetle chronologicznie (sekwencyjnie) dopełniających się wskazań odnośnie do formacji katechetów, pozwoliła na wyodrębnienie mistagogicznych elementów teologiczno-pastoralnej formacji katechetów. Wyrażony w Dyrektorium katechetycznym postulat formacji katechetów jako „świadków wiary i mistagogów” oraz ustanowioną przez Franciszka posługę świecką katechety artykuł akcentuje jako możliwość i konieczność formacji dwóch dopełniających się dzięki posiadanym kompetencjom typów katechetów: katechety szkolnego – nauczyciela religii, oraz katechety (katechisty) – podejmującego posługę we wspólnocie parafialnej. Jako przykład katechetyczno-duszpasterskiej realizacji postulowanych działań przedstawiono inicjatywy duszpasterskie wspierające formację katechetów parafialnych prowadzone w Archidiecezji Katowickiej. Stanowią one inspirację dla działań podejmowanych w innych ośrodkach formacyjnych.