bluuebunny/crossref_metadata_2025_split huggingface dataset:
Muscle ultrasonographic changes in critically ill COVID-19 patients
Authors: Torres-Mora Johan Sebastian , Cuellar-Fernández Yeny , Medina-Parra Jorge , Merchán-Chaverra Ricardo Alfonso 
Published: August 2023

Background: Patients with severe forms of COVID-19 (coronavirus disease 2019) present a systemic inflammatory response and hypermetabolism. The objective of this study was to identify the change in rectus femoris and vastus medialis muscle mass in patients with severe COVID-19 who required invasive mechanical ventilation, and to establish the correlation between the change in muscle size and the amount of calories and proteins administered.
Materials & methods: This prospective observational longitudinal study was conducted in the adult intensive care unit in a tertiary care clinic. Muscle mass was measured with ultrasound from admission, at seven-day intervals, until discharge from the unit. Anthropometric and biochemical data as well as the amount of calories and proteins administered were taken into account.
Results: A total of 39 patients were included (59.6 ± 11.3 years; 79.5% men) with a median BMI of 27.7 kg/m2 (IQR 24.2–29.7). The size of the rectus femoris and vastus medialis muscles had diminished significantly at seven days of hospitalization: right middle third 0.38 cm (IQR 0.16-0.47), left middle third 0. 29 cm (IQR 0.08-0.54) and right middle third 0.37 cm (IQR 0.11-0.71) left middle third 0.25 cm (IQR 0.09-0.52), respectively. The changes in both muscles were directly correlated with caloric and protein intake during nutritional support.
Conclusions: Critically ill patients with COVID-19 were found to lose muscle mass progressively as a result of lower coverage of caloric and protein requirements.
On modules over the mod 2 Steenrod algebra and hit problems
Authors: Võ Phúc Đặng 
Published: August 2023

<p>We will look at the binary field $\mathbb F_2$. The classical "hit problem" in algebraic topology, which is widely considered to be an important and fascinating open problem that has yet to be resolved, asks for a minimal set of generators for the polynomial algebra, $\mathcal P_m:=\mathbb F_2[x_1, x_2, \ldots, x_m]$, on $m$ variables $x_1, \ldots, x_m$, each of which has degree one, regarded as a connected unstable module over the 2-primary Steenrod algebra $\mathscr A.$ The algebra $\mathcal P_m$ is the cohomology with $\mathbb F_2$-coefficients of the product of $m$ copies of the Eilenberg-MacLan complex $K(\mathbb F_2, 1)$. Despite extensive study over the past three decades, the hit problem remains unresolved for $m\geq 5$. </p>
<p>In this article, we develop our previous work [Commun. Korean Math. Soc. \textbf{35} (2020), 371-399] on the hit problem for the $\mathscr A$-module $\mathcal P_5$ in the generic degree $n_s = 5(2^{s}-1) + 18.2^{s}$ with $s$ an arbitrary non-negative integer. As a consequence, a localized variation of the Kameko conjecture, which concerns the dimension of the cohit space $\mathbb F_2\otimes_{\mathscr A}\mathcal P_m$ in relation to parameter vectors, has been claimed to be veracious in the instance where $m = 5$ and the degree is $n_s.$ Also, we demonstrate that this conjecture remains valid for all $m\geq 1$ and degrees $\leq 12.$ This study has two important applications: (1) it establishes the dimension result for the cohit space $\mathbb F_2\otimes_{\mathscr A}\mathcal P_m$ for $m = 6$ in the generic degree $5(2^{s+4}-1) + n_1.2^{s+4}$ with $s > 0;$ and (2) it describes the representations of the general linear group of rank $5$ over $\mathbb F_2.$ As a result, we prove that the algebraic transfer, defined by William Singer [Math. Z. \textbf{202} (1989), 493-523], is an isomorphism in bidegrees $(5, 5+n_s)$ with $s\geq 0.$ Besides, we obtain new results on the behavior of this algebraic transfer for all homological degrees $m$. Specifically, we show that Singer's transfer is a trivial isomorphism in bidegree $(m, m+12)$ for any $m > 0$. At the end of this work, we discuss the hit problem for the symmetric polynomial algebra $\mathcal P_m^{\Sigma_m}.$ This topic has been previously studied by Ali Janfada and Reginald Wood for $m\leq 3.$</p>
Structure of the space of GL4 (Z2)-coinvariants Z2 ⊗ GL4 (Z2) P H∗ (Z42,Z2) in some generic degrees and its application
Authors: Võ Phúc Đặng 
Published: August 2023

<p>Fix $k = \mathbb Z_2$ to be a field of characteristic 2, let $A$ denote the Steenrod algebra over $k.$ A problem of immense difficulty in algebraic topology is the determination of a minimal set of $A$-generators for the polynomial ring $P_q = k[x_1, \ldots, x_q] = H^{*}(k^{q}, k)$ on $q$ generators $x_1, \ldots, x_q$ with $|x_1|= |x_2| = \cdots = |x_q| = 1.$ By way of equivalence, one may choose to write an explicit basis for the cohit space $\pmb{Q}^{q} := k\otimes_{A} P_q$ in each non-negative degree $n.$ This subject, which has now a long history, is the content of the classical "hit problem" proposed in [Abstracts Papers Presented Am. Math. Soc. \textbf{833} (1987), 55-89]. Furthermore, it is closely related to the $q$-th transfer homomorphism $Tr_q^{A}$ constructed by William Singer in [Math. Z. \textbf{202} (1989), 493-523]. This map $Tr_q^{A}$ passes from the space of $G(q)$-coinvariant $k\otimes _{G(q)} P_A((P_q)_n^{*})$ of $\pmb{Q}^{q}$ to the $k$-cohomology group of the Steenrod algebra, ${\rm Ext}_{A}^{q, q+n}(k, k),$ wherein $G(q)$ stands for the general linear group of degree $q$ over the field $k,$ and $P_A((P_q)_n^{*})$ is the primitive part of $(P_q)^{*}_n$ under the action of $A.$ Particularly, the assertion that $Tr_q^{A}$ is always an injective map has been conjectured by Singer himself, but as of now, this remains an open problem for all $q\geq 4.$ Accordingly, the aim of the present study is to deal with the Singer conjecture for rank 4 in certain internal degrees. Specifically, by the usage of the techniques of the hit problem in four variables, we explicitly determine the structure of the coinvariant $k\otimes _{G(4)} P_A((P_4)_{n}^{*})$ in some generic degrees $n.$ Then, applying these results and a representation of $Tr_4^{A}$ via the lambda algebra, we state that Singer's conjecture is true for rank $q = 4$ in respective degrees $n.$ This has significantly contributed towards the ultimate proof of Singer's conjecture within the rank 4 case.</p>
Coverage Analysis of IRS-Aided Millimeter-Wave Networks: A Practical Approach
Authors: Etcibasi Abdullah , Aktas Emre 
Published: August 2023

<p>Intelligent reflecting surfaces (IRSs) have become a popular topic in recent years for their great potential for controlling the radio link environment of wireless networks. With this controlled environment, the coverage can be increased. This paper examines the coverage analysis of IRS-aided networks, considering both two-dimensional buildings and the product-distance path loss model for the first time. Leveraging the tools from stochastic geometry, the locations of base stations (BSs), buildings, and IRSs are modeled with a homogeneous Poisson point process (PPP). A Gamma approximation for the distribution of the nearest line-of-sight (LoS)-neighbor distance is proposed, leading to a closed-form expression for the distribution of the product-distance. Feasible BSs are defined as BSs which are reachable via an IRS deployed on a specific facade of a building, and the ratio of feasible BSs is derived. Simulations are performed, which confirm the proposed analytical methods. In the numerical results, it is observed that the IRSs can introduce up to a 45\% coverage boost, and the effect of the IRS length on the coverage probability is limited beyond 1.2 meters at 60 GHz.</p>
The Generation of Semantics in Natural Language and the Formation of Brain Intelligence
Authors: Tang Lei 
Published: August 2023

<p>In nature, the intelligence phenomenon that exists with the matter form was originated from the motion and interaction between a great number of microscopic matters. At the first step of intelligence development, intelligent agent needs being able to represent and recognize various external stimulations. Therefore, after this paper first introducing the characteristics of neuron, we next introduce that human brain is how to represent color and sound stimulations through the radial basis function principle, and for color representation we use a quantitative analysis method to approximately estimate the number of basis color attributes. To object shape representation, it is known that the simple neuron in the primary cortex is able to extract the direction information of a line, and following this we have introduced the concept of line segment directional spectrum that can represent the direction characteristic and bending degree of a line segment, and analogously through the representation principle of the three primary directions as that of the three primary colors in visible spectrum the vision system also could efficiently represent the characteristic information of a line segment. Specially, we should note that the representation of line segment direction actually belongs to a class of more advanced characteristic representation, the vision system usually first extracts the topology characteristics in shape. In addition, we have emphasized that the semantics in natural language exist in the neural fiber plexus nodes of our brains and have introduced the relationships of shape, semantics and attention mechanism in cognitive behavior. Note that human knowledge is represented through natural language, this paper also elucidates the principle of matter primacy. Through summarizing the evolutionary process of human intelligence, we have found that the subjective initiative of humans in behavior is most important characteristic that distinguishes humans from animals. At the end of this paper, we explain that why the brain consumes less power and the limitations of human intelligence.</p>
PELATIHAN PENERAPAN MEDIA PEMBELAJARAN DARING YANG EFEKTIF DALAM MASA PANDEMI COVID 19
Authors: Rasyid Hamidi , Rustantono Hendra , Maslahah Wafiyatu , Rofiah Lailatul , Maida Nur Al 
Published: August 2023

Kegiatan ini di latar belakangi keterlambatan guru untuk beradaptasi dengan pembelajaran online atau daring, hal itu disebabkan karena guru sebelumnya belum terbiasa dengan pembelajaran daring, akan tetapi dengan adanya wabah covid 19 dan peraturan pemerintah bahwa pembelajaran harus secara daring, maka kami mempunyai inisiatif untuk memberikan pelatihan kepada guru dalam menggunakan media daring yang efektif dalam masa pandemi Covid 19. Kegiatan ini dilakukan di ruang kelas MA Darul huda Klepu. Kegiatan ini dilaksanakan selama satu kali pertemuan dengan materi yaitu pelatihan menggunakan video pembelajaran KineMaster. Pesertanya terdiri dari Guru dan Kepala Sekolah. Hasil dari analisis kegiatan tersebut bisa disimpulkan bahwa terjadi peningkatan pemahaman guru dalam menggunakan media pembelajaran daring dalam proses belajar mengajar, hal itu bisa terlihat dari kemampuan guru dalam membuat Video pembelajaran menggunakn KineMaster.
The development of triangular kinematic module to calculate the deformation pressure in the extrusion processes
Authors: Aliieva Leila , Levchenko Volodymyr , Aliiev Igramotdin , Kartamyshev Dmytro 
Published: August 2023

Аliieva L. І., Levchenko V. M., Aliiev I. S., Kartamyshev D. O. The development of triangular kinematic module to calculate the deformation pressure in the extrusion processes
The article presents the universal kinematic module developed on the basis of the energy upper bound method, designed for use in mathematical simulations of combined processes of cold forging. In particular, this module can be used for force regime simulating and tool loads analyzing at radial-forward extrusion of hollow products with blind hole of continuous workpieces to describe deformation zones during metal flow to the center and turn zones from radial flow to backward one. The kinematically possible velocity field for convex curvilinear (parabolic) triangular module and the equations of its parabolic inclined boundary are given. Analytical dependencies for power of deformation forces, friction and shear at the boundaries of the module, as well as for the reduced pressure in a parametric form are obtained. The developed curvilinear kinematic module, the use of which makes it possible to increase the efficiency of the upper bound method for studying the processes of combined extrusion, has been tested and described. It is shown that value of reduced pressure for the curvilinear turn module is most affected by the relative thickness of the flange, its radius, the thickness of the wall of the tubular workpiece, as well as friction conditions. The possibility of correct using of curvilinear triangular module for the analysis of complex schemes of processes with several zones is demonstrated. The simulation for calculation schemes of radial-forward workpiece extrusion with variable flange height was carried out. It has been determined that the developed curvilinear triangular module due to the reducing the value of the velocity jump at its boundaries, makes it possible to reduce the upper estimate of the tool loads in comparison with the variants of simulations that were previously based on rectangular modules.
Простой способ оценки производной эмпирической функции по ее значениям в неравноотстоящих точках
Authors: Beygelzimer Emmanuil , Beygelzimer Yan 
Published: August 2023

Бейгельзимер Э. Е., Бейгельзимер Я. Е. Простой способ оценки производной эмпирической функции по ее значениям в неравноотстоящих точках
Предложена эвристическая формула 5-точечной аппроксимации первой производной неизвестной функции, значения которой измерены с погрешностью в неравноотстоящих точках. Расчет производной в данной точке выполняется по эффективным приращениям функции и аргумента, учитывающим разные весовые коэффициенты для ближних и удаленных точек измерений. Для определения рациональных значений весовых коэффициентов применено имитационное моделирование на тестовых функциях с известными производными. Детально описаны результаты моделирования на двух тестовых функциях, одна из которых имитирует процесс водяного охлаждения горячего стального листа, вторая – сложный колебательный процесс с переменной частотой и амплитудой. Установлено, что оптимальные значения весовых коэффициентов остаются примерно одинаковыми для существенно разных функций, что позволяет рекомендовать одну и ту же формулу для всех случаев. В отличие от классических методов численного дифференцирования функций, табулированных в неравноотстоящих узлах, предложенная формула одновременно учитывает сглаживание эмпирических данных. Показано, что это существенно повышает точность численной оценки производной даже в тех случаях, когда случайная погрешность измерения функции составляет весьма малую величину, - от ± 1 %. Полученная формула рекомендуется к использованию при решении любых задач ОМД, требующих оценки производной эмпирической функции, в том числе при расчете напряженно-деформированного состояния металла, описании тепловых процессов, определении теплофизических свойств материалов.
Вплив швидкості деформування на гаряче зворотне видавлювання осесиметричного порожнистого виробу
Authors: Kaliuzhnyi Vladymyr , Levchenko Volodymyr , Yarmolenko Oleksandr , Tahan Liubov 
Published: August 2023

Калюжний В. Л., Левченко В. М., Ярмоленко О. С., Таган Л. В. Вплив швидкості деформування на гаряче зворотне видавлювання осесиметричного порожнистого виробу
Моделюванням методом скінченних елементів вивчено вплив швидкості деформування на процес гарячого зворотного видавлювання з осаджуванням із високовуглецевої сталі осесиметричного порожнистого виробу з виступом на торці донної частини. Швидкість переміщення пуансону змінювалася від 50 до 400 мм/сек. Проведено розрахунковий аналіз процесів видавлювання з осаджуванням, процесів вилучення пуансонів із здеформованих заготовок та процесів виштовхування виробів із матриць. Встановлено залежності зусилля видавлювання від переміщення пуансона, залежності зусилля вилучення пуансона від його зворотного переміщення і залежності зусилля виштовхування виробу з матриці від переміщення виштовхувача. За величинами нормальних напружень визначено розподіл питомих зусиль на торцях пуансона, виштовхувача та по висоті поверхні матриці. Збільшення швидкості деформування з 50 до 200 мм/сек призводить до суттєвого зниження зусилля деформування. Подальше зростання швидкості мало впливає величину зусилля. Наведено рекомендації щодо вибору пресового обладнання. Для кінцевої стадії видавлювання з осаджуванням показано розподіл температури, компонент напружень і деформацій в деформованому металі. Визначено температуру охолодження в шарах металу, розташованих поблизу контактуючих поверхонь. Встановлено кінцеві форма та розміри виробу. Для одержання рівного торця стінки необхідна додаткова операція його підрізання. Проробку структури металу пластичною деформацією оцінено за величиною інтенсивності деформацій у стінці та донній частині виробу. Одночасне формоутворення зворотним видавлюванням з осаджуванням призводить до більш інтенсивного пропрацювання структури металу пластичною деформацією і знижує нерівномірність інтенсивності деформацій по ширині стінки виробу.
Descripción Clínica de los Pacientes Pediátricos Oncológicos con Neutropenia Febril Ingresados a la Unidad de Cuidados Intensivos de la Unidad Nacional de Oncología Pediátrica
Authors: Gavidia Mayora Gabriela Marina , Armendáriz Ortíz Amanda Lucía , Mack Rivas Ricardo Alfredo 
Published: August 2023

Objetivo: Describir las características clínicas de los pacientes pediátricos oncológicos que fueron diagnosticados con Neutropenia Febril (NF) ingresados por primera vez a la Unidad de Cuidados Intensivos (UCI) de la Unidad Nacional de Oncología Pediátrica (UNOP). Métodos: Estudio descriptivo y retrospectivo, se caracteriza un total de 211 pacientes que desarrollaron NF y requirieron ingreso a la UCI, entre los años 2017 a 2021. Resultados: La edad promedio fue de 8 años, 46% fueron hombres y 54% mujeres. Se presentó neutropenia severa en el 72.77% de los casos y la leucemia (81.99%) fue el diagnóstico oncológico destacado. Dentro de todos los tratamientos, el 38.39% de los pacientes se encontraban en fase de inducción. En un 33.18% se logró identificar un agente infeccioso asociado. Las bacterias de tipo Gram-negativo fueron el agente infeccioso causal más frecuente (13.74%). La media del tiempo de estancia en UCI fue de 6.75 ± 5.79 días. Un 91.62% de pacientes no ameritaron ventilación mecánica y la complicación más frecuentemente asociada a NF fue Sepsis en un 65.88% de los casos. Conclusión: La mayoría de los casos de Neutropenia Febril son severos, las neoplasias hematológicas (LLA y LMA) son la enfermedad de base más frecuente para el desarrollo de NF y las bacterias de tipo Gram-negativo son el agente infeccioso más frecuente. La mayoría de los pacientes no ameritan ventilación mecánica y las complicaciones más frecuentemente asociadas son Sepsis y Neumonía.
Analisis Perbandingan Tingkat Keuntungan Dan Risiko Portofolio Dengan Menggunakan Model Indeks Tunggal Dan CAPM
Authors: Achmad Daniel Noor , Yudha Andi , Bela Marita 
Published: August 2023

The purpose of this study is to determine the level of retum and risk from a portfolio using Single Index method and CAPM measured using average yield, while the risk ofportfolio is measured by Single Index model calculated using variance, while the risk is measured using CAPM model by beta value (market risk). The analysis used in this study is comparing results of calculation using formulas both Single Index and CAPM models. The fonnulas include methods to measure the return and risk of a stock portfolio. Beta factor is used to measure the sensitivity of the portfolio to the market and both models use the same calculation. The period of this study is during August 2012 — January 2013 by using index data to determine the level of expected return and the risk of each portfolio. The result shows that the highest average expected return rate in the period ofstudy which using the Single Index Model is owned by Sri-Kehati portfolio that has an average rate of return amount 0.0009 and has as small risk of total consisting in market company risk with an amount of 0.00007. Furthermore the smallest return in average is owned by Pefind025 with the amount of 0.0004 and the highest risk with the amount of 0.00010, and the pefind025 portfolio has the smallest beta. In CAPM model we found that all portfolios has negative return and negative risk premises which means six ofthe portfolios do not meet the expected returns.
Keywords: return, risk, beta, Single Index Model, CAPM
Pengaruh Kualitas Produk Dan Kualitas Pelayanan Terhadap Kepuasan Pelanggan Pada PDAM Tirta Pakuan Kota Bogor
Authors: Retna Dewi Wulan , Sulistiono Angga 
Published: August 2023

In the free trading era, many companies are met with increasing consumer demands. Companies must provide service excellenæ to satisfr customets. The serviæ quality has a closed relationship with the customer satisfaction. PDAM Tirta Pakuan Kota Bogor, as a public service company, develops the products and services quality. The companies' strategies are providing a goodfoundation for business continuity, encourage the creation ofcustomer satisfaction, establish recommendations through word of mouth. The purpose of this study is to examine the effect of product quality and service quality on customer satisfaction. The results showed that the regression equation ofproduct quality and service quality on customer satisfaction is: Y = 7.054 + 0.164 XI + 0.468 X2. It means that all the independent variables has a positive effect on customer satisfaction. The hypothesis test ofpartial variable product quality and service quality showed significantly, because all the significant value under 0.05. Product quality has significantly positive effect on customer satisfaction. The result ofsimultaneous hypothesis testing are rejecting HO and accepting HI. So it can be concluded that the product quality (XI) and service quality (X2) simultaneously influenæ the customer satisfaction variable. Based on the result study, The Product Quality and Service Quality are the important components to be increased by PDAM Tirta Pakuan Kota Bogor.
Keywords: quality products, quality service, customer satisfaction
Pengaruh Hutang Jangka Pendek Dan Hutang Jangka Panjang Dalam Menilai Kinerja Perusahaan Dari Aspek Profitabilitas
Authors: Supriadi Yoyon , ALFIANA M. NUR 
Published: August 2023

Firms are facing dificulties in running business if only using internal source of funds. The growth or development of a company results in the need for greater funding. Hartono (2000, 254), mentions that the debt contains risk. The higher the risk of a company, the higher the level ofprofitability expected in retumfor the high risk and conversely the lower the risk of the company, the lower the level of profitability expected in return for lower risk. This study tries to investigate the effect of short and long term debts on company's performance when viewed from its profitability aspect. The results showed that simultaneous independent variables Y1(Return on Assets) and the independent variable Y2 (Return On Equity) there is no significant effect on the independent variable. The coeficients determinations show that there are other variables that determine the returns or profitability. Based on the establishment of the regression equation suggests that if there is an addition of one - unit on the coefficients Change of Debt Short - Range and the Longterm Debt Equity Retum on Assets will decrease, as well as in the event ofone - unit increments of the coefficients Change of Debt Short - Range Longterm Debt Equity and the Retum On Equity will decline .
Keywords: long-term debt, profitability