bluuebunny/crossref_metadata_2025 huggingface dataset:
N-Gram-Codon and Recurrent Neural Network (RNN) to Update Pfizer-BioNTech mRNA Vaccine
Authors: Bouarara Hadj Ahmed
Published: July 2022

In the fight against SARS-CoV-2, Pfizer BioNTech based on synthetic messenger RNA (mRNA) proved to be quicker and more effective even with a small dose of micrograms per injection. Unfortunately, such a vaccine requires very low temperatures to prevent degradation of mRNA. In this paper, we have developed three new models of recurrent neural network (1- simple LSTM 2-BDLSTM 3-BERT) using n-gram-codon technique for the codification of mRNA. The primary aim is to analyse the mRNA sequence and predict the stability/reactivity rates at various codon positions. The results of the predictions will be presented in the form of recommendations to support laboratories in updating Pfizer's BioNTech vaccine. The obtained results were validated by the Stanford OpenVaccine dataset and the evaluation measures recall, precision, f1-score, accuracy and loss.
Simply and Controllably Syntheszing Micro-Nano Barium Titanate Ceramics
Authors: Song En Peng , Jin Quan , Cai Ke , Chen Fen Hua , Liu Zhao
Published: July 2022

The micro-nanoBaTiO3 ceramics of different sizes have been prepared simply and controllably via a self-assembly sintering method. The effects and scopes of the application of this method in the controllable synthesis of the micro-nanoBaTiO3 ceramics are investigated. Through the given size of BaTiO3 powders and the combination way, the ceramics with different grain sizes, such as 400~500 nm, can be controllably synthesized. Therefore, the use of this method is conducive to the realization of the controllable synthesis of the micro-nanoBaTiO3 ceramics.
First-Principles Study of the Optical Properties of Zinc Antimonide Using the mBJ Approximation
Authors: Malki Siham , Darhi Zakariae , Guesmi Ibtissam , El Farh Larbi , Challioui Allal
Published: July 2022

This computational study focused on the optical properties of zinc antimonide ZnSb. It relates to the complex dielectric function ε (ω), the refractive index n (ω), the extinction function k (ω), the optical conductivity σ (ω), the reflectivity R(ω), the absorption coefficient α (ω) and the energy loss spectrum L(ω). These properties are calculated and discussed for a growing energy of the incident electromagnetic radiation ranging from 0 to 14 eV, comprising infrared, visible and ultraviolet regions. All these properties are obtained using the Full Potential Linearized Augmented Plane Wave (FP-LAPW), by solving Kohn-Sham equations. This method based on Density Functional Theory (DFT), implemented in Wien2k simulation package. This compound is already used in photo-optical applications, it is for this reason that we interested in the calculation of its optical properties according to the energy of the incident photons, in order to open up for it other use ways. Since the zinc antimonide ZnSb is a semiconductor, its optical properties are investigated using Generalized Gradient Approximation plus modified Becke–Johnson as the exchange correlation (GGA-mBJ). Our calculations are performed by considering only the interband transition of electrons between the occupied states in valence band and unoccupied conduction band states along high symmetry points in Brillouin zone. In addition, the relations of the optical properties to these transitions are discussed in detail. We have also verified the Penn’s model by showing the inverse relationship between the static real part of dielectric function ε1(0) and the optical band gap Eg. The results obtained are compared with other results existing in the literature.
Study of the Structural, Electronic and Optical Properties of 1T-ZrX2 Materials (X=S, Se, Te)
Authors: Guesmi Ibtissam , Challioui Allal , El Farh Larbi , Malki Siham , Darhi Zakariae
Published: July 2022

The Electronic and optical properties of zirconium dichalcogenides (ZrS2,ZrSe2, andZrTe2),have been explored via ab-initio methods based on the density functionaltheory (DFT) within the frame of generalized gradient approximation (GGA) and a couplingtechnique between the plane wave (PW) and the pseudo-potential (PP) approaches. Theobtained results showed that ZrS2 and ZrSe2 are semiconducting materials with energy gapsof 1.15 eV and 0.3 eV respectively from the valence band maximum located at G point andthe conduction band minimum located at L point, while ZrTe2 showed a metallic characterwith a density of states at the Fermi level of about 0.8 states/eV. Based on a Kramers–Kroniganalysis of the reflectivity, we have obtained the spectral dependence of the real andimaginary parts of the complex dielectric function (ε1 and ε2, respectively) and the refractiveindex (n). The collected data were used for the calculation of absorption coefficient,reflectivity index, conductivity, and electron energy loss function of ZrS2, ZrSe2, and ZrTe2 forradiation up to 20 eV. All three chalcogenides were found to be good absorbers of ultravioletradiation. The reflectivity of ZrS2 is low in the visible and near-ultraviolet region butincreases sharply for higher photon energies and approaches 96% at ~18.5 eV. The R(ω) spectrum of ZrTe2, on the other hand, is non-selective and remains above 50% over a widerange of energies from infrared to ultraviolet which suggeststhe potential application of thismaterial as an effective solar reflector. On the other hand, the refractive indices of ZrS2, ZrSe2,and ZrTe2 in the visible range are high. The optical spectra show moderate anisotropy concerning the electric field polarization of the incident light.
Technology of Preparing Ceramsite from Electric Ceramic Waste
Authors: Zhong Lu , Yang X.Q. , Song Jie Guang , Liu Yue , Zhu W.L. , Wen H.B. , Liu Y. X.
Published: July 2022

With the popularization of electricity, the use of electric porcelain is becoming more and more extensive, but in the process of production, the waste of electric porcelain continues to accumulate and increase, which not only pollutes the environment but also affects the normal life of human beings. Therefore, it is urgent to deal with these electric porcelain wastes. In this paper, the electric ceramic waste is used as the main raw material, and starch and kaolin are added to optimize the formula to prepare porous ceramsite. The effects of the content of electrical ceramic waste, sintering temperature and holding time on the properties of porous ceramsite were studied. After research, the results show that with the increase of waste content, the porosity and water absorption first decrease and then increase, while the compressive strength first increases and then decreases. With the increase of the sintering temperature, the porosity and the water absorption rate decrease continuously at the beginning, and the compressive strength increases continuously at the beginning, but when the sintering temperature increases continuously, there will be a turning point or a flattening point. With the continuous extension of the holding time, the water absorption and porosity continue to increase, while the compressive strength continues to decrease, but the overall change is small. The optimization can be found that when the waste content is 75%, the sintering temperature is 1200 °C, and the holding time is 30 min, the prepared porous ceramsite has the best performance. Its water absorption rate: 13.87%, porosity: 27.52%, compressive strength: 20.06MPa.
Production of Phenolic Foams Based on Phenol-Formaldehyde Oligomers of Reduced Toxicity and Material Consumption
Authors: Bruyako Mikhail G. , Aleksandrova Olga V. , Golotenko Daria
Published: July 2022

This article presents the results of studies considering the possibility of obtaining products based on phenol-formaldehyde oligomers of reduced toxicity, material consumption and corrosive activity. This is achieved by removing free phenol and formaldehyde monomers from the foaming composition and by more complete implementation of hydrodynamic processes during foaming of the composition. The article includes the results of studies on finding the ratio of the initial components and its effect on the corrosive activity of finished products. It is also considered the determination of the dependences of the toxicity and material consumption of phenolic foams on the pressure gradient of the foaming composition and the environment. For the research, the FRV-1A resole prepolymer and the VAG-3 foaming-hardening agent were used as raw materials. The content of phenol and formaldehyde monomers was determined by gas chromatography. In this work, the diagram of installation is developed and presented. It consists of a high-pressure machine, a mold, a vacuum pump, a vacuum gauge, air supply and air removal pipes. The results indicate that ensuring the formation of a cellular structure of phenolic foam in the low-pressure zone makes it possible to obtain heat-insulating products based on phenol-formaldehyde oligomers of reduced toxicity, material consumption and corrosive activity.
Designing Barium Titanate Ceramics with High Energy Storage and Mechanical Properties
Authors: Jin Quan , Song En Peng , Cai Ke , Chen Fen Hua , Liu Zhao
Published: July 2022

Designing the fine-grained ceramics with high recoverable energy storage density and excellent mechanical performance, still presents great challenges. Because the ceramics with large pore size and low relative density were obtained by the traditional sintering method, they always exhibit small breakdown strength and poor mechanical properties, which limits the miniaturization and operation of devices in harsh environments. In this paper, we designed the barium titanate ceramics (BT) ceramics with grain size of 252 nm and relative density of 0.92 can be obtained via co-sintering of two sizes of BT particles at 1000 °C for 10 h. The cubic phase BT particles with 80 nm are doped in the tetragonal phase BT particles with 200 nm to obtain tetragonal phase fine-grained BT ceramics. When doped with 80 nm BT particles, the sintering of 200 nm BT particles is promoted. The enhanced sinterability is due to the phase transformation and metastability, which act as sintering aids. The obtained BT ceramics with nanodomains, high energy storage and mechanical properties. The discharge energy density is of 0.81 J/cm3, and the Vickers hardness is 1.75 GPa.
Uncorrelated Excitonic Properties in Multilayered Cylindrical Quantum Dot
Authors: Hbibi Mohammed , Mommadi Omar , Boussetta Reda , Chouef Soufiane , Belamkadem Laaziz , El Moussaouy Abdelaaziz , Vinasco Juan Alejandro , Duque Carlos Alberto , Falyouni Farid
Published: July 2022

The unbound exciton properties in multilayered cylindrical quantum dot (CQD) (core/shell/shell) have been studied theoretically, within the effective mass approximation and two-band model. The uncorrelated energy of an exciton confined in GaAs/Ga1-x1Alx1As/Ga1-x2Alx2As CQD as a function of the core and first shell radius is presented. The numerical results show that the quantum dot size and the confinement potentials depth significantly adjust the ground state uncorrelated energy of exciton. However, the exciton wave function parameters are dependent on the core and first shell radius (R1 and R2), as well as the concentration of the barrier’s materials.
Combined Heat Treatment Method for Producing of Ultra-High Performance Concrete
Authors: Soloviev Vadim , Efishov Luka , Matyushin Evgenij
Published: July 2022

Decreasing an overall time of curing for UHPC products is a perspective task that can be solved by combining different heat treatment technologies. The paper presents the results of studying the UHPC microstructure after combined steam and non-steam heat treatment. Concrete specimens after demolding were steam cured for 16 hours, than – in oven camber. Heat treatment in oven chamber for 8 hours under temperature 250 ̊С leads to micro-defects self-healing, due to the new crystalline phase formation. The combined heat treatment allows unleashing of additional potential of UHPC mixes, which could take years in normal conditions The considered curing method with further treatment in oven can not only accelerate the process, but also unleash the additional part of UHPC pozzolanic potential for different mix compositions.
A review on prioritizing physical safety and comfort in urban sustainability assessment tools to effectively control accidents in streets of Colombo
Authors: Kumaraguruparan A. , Wijesundara K. W. J. P. , Weerasinghe U. G. D.
Published: July 2022

The concept of sustainability has evolved since its initial definition by the Brundtland commission in 1987, and become comprehensive over time with inclusion of well-defined social, environmental and economic aspects. In order to understand the progress of sustainability, and facilitate decision making, various sustainability assessment tools were established. Today it has become necessary to include safety and comfort as criteria of such sustainability assessment tools, considering the high number of accidents and crimes taking place in urban contexts despite all the legal reforms made through several years to control user misbehaviours. A high number of road accidents are recorded in Colombo as per the report issued by the Sri Lanka Department of Census and Statistics. This is primarily due to lack of obligation to enforce physical safety and comfort aspects. Establishing physically safe and comfort streets could contribute to prevent as well as reduce accidents by spontaneously directing users in the right way. Therefore, considering sustainability principles, and sustainability rating, being a well-established universal quality assessment, it is important to incorporate physical safety and comfort as a criteria of sustainability rating of urban streets. The review is done by initially defining sustainability through literature review, identifying the research gap on physical safety and comfort using VOSviewer software, and assessing the significance of safety and comfort in assessing urban streets using available online data. It is identified that physical safety and comfort is not included in most of the sustainability assessment tools. It is suggested that inclusion of these criterion could contribute in effectively reducing the street accidents. Summary of this review could contribute in further research based on sustainability tool criteria assessments.
Thermal performance and user perception on mud concrete floor compared to the other floors
Authors: Galabada G. H. , Dharmarathne P. D. , Galkanda Himahansi , Halwatura R. U.
Published: July 2022

New building materials and technologies that provide thermal comfort are expected to gain popularity in the recent past. Hence, efforts to incorporate new building materials are needed to protect populations from the threats of thermal stress that cause an increase in temperatures due to climate change. The earth is identified as the most effective building material to improve the thermal comfortability inside the building. Among several building construction materials, the flooring material provides a more effective role with respect to thermal comfort in a building. This paper presents the evaluation and comparison work carried out to investigate the thermal performance and user perception of newly invented soil based flooring material with other common floorings in Sri Lanka. Temperature measurements were taken on the top surface of flooring materials and were compared the surface temperature of each other and indoor air temperature. User perception was taken through a questionnaire survey by involving hundred and twenty numbers of responses. The results reveal that the soil floor shows a lesser surface temperature at a significant level than the other floorings. Hence, it can be proved that the building construction materials play an important role and earth is one of the most sustainable materials with respect to the indoor thermal comfortability thus, end-user.
Editorial
Authors: Thayaparan Menaha
Published: July 2022

No abstract available
Ruolo del D-chiro-inositolo nella gestione del diabete mellito gestazionale: impatto su outcomes materni e fetali
Authors: Narcisi Selene , Allasia Stefano , Balbo Marcella , Cappa Cristina , Gabellieri Enrico , Leporati Paola , Lucatello Barbara , Ragni Alberto , Gallo Marco
Published: July 2022

Introduzione. Il D-chiro-inositolo (DCI) è un mediatore dell’azione insulinica e ha dimostrato di migliorare i parametri metabolici delle donne con diabete gestazionale (GDM). L’obiettivo di questo studio è valutare l’impatto della supplementazione di DCI sul controllo metabolico e gli esiti materni e fetali delle donne affette da GDM.

Pazienti e metodi. È stata valutata retrospettivamente una coorte di 20 donne affette da GDM, trattate con dieta standard e, in metà dei casi, supplementate con DCI. Sono stati valutati e confrontati nei due gruppi (DCI vs controllo) vari parametri (compenso glicemico, dose insulinica totale, parametri biometrici materni e fetali).

Risultati. Il gruppo DCI ha mostrato una tendenza a una minor dose insulinica giornaliera, a glicemie postprandiali più basse e un minor peso al parto, mentre i feti del gruppo DCI avevano una minor circonferenza addominale e un minor peso alla nascita. A causa della bassa numerosità, le differenze riscontrate non sono risultate statisticamente significative.

Conclusioni. La supplementazione di DCI nel GDM è sicura e sembra migliorare, in associazione a terapia standard, i parametri metabolici materni, oltre che esercitare un ruolo favorevole sullo sviluppo fetale.
Perceived factors contributing to the care provided by informal (family) and formal caregivers of older adults with noncommunicable diseases in rural communities
Authors: Sangsaikaew Amornrat , Junsevg Khunphitha , Thong-On Rattiya , Pilayon Benjayamas
Published: July 2022

BACKGROUND:

Informal and formal caregivers of older adults with noncommunicable diseases (NCDs) are important in every aspect of current caregiving for older adults by understanding reality specific to direct experiences perceived by each person in caring for older adults in order to develop nursing knowledge and using knowledge to plan care for older adults with NCDs to have a good quality of life. The current study aimed to investigate the points of view on factors concerning the care provided by informal and formal caregivers providing care for older adults with chronic diseases in the community.

MATERIALS AND METHODS:

This study was conducted with a qualitative design. The sample was 5 informal and 20 formal caregivers providing care for patients with chronic diseases, namely hypertension and diabetes mellitus. Furthermore, a qualitative approach was used with four focus groups (FGs) with 25 informants. Data were collected during March–August 2021 in rural communities of Nakhon Phanom Province, Thailand. Finally, the qualitative analysis used content analysis; FG data were analyzed using content analysis in which a preliminary set of codes was determined according to other documented experiences of patients.

RESULTS:

The findings revealed three main themes emerging in the data obtained on the perceived factors contributing to the care provided by informal and formal caregivers: “caregivers' knowledge,” “factors related to caregivers” and “community factors.”

CONCLUSION:

Points of view on the factors correlated with the care provided by informal and formal caregivers of older adults with chronic diseases that explain and confirm the findings can be used to plan care with effects on quality of life among older adults with chronic diseases.
Online medical teaching during COVID-19
Authors: Rohila Jyoti , Kapoor Kanchan , Singh Jyotsna , Rohilla Ravi , Bansal Palak , Chhabra Palak
Published: July 2022

BACKGROUND:

Online teaching has been practiced after lockdown due to Coronavirus Disease 2019 (COVID-19) pandemic which has replaced conventional classroom teaching. The aim of the present study was to know the perceptions regarding online learning as perceived by both teachers and students during COVID-19 pandemic.

MATERIALS AND METHODS:

The present study was cross-sectional and questionnaire-based. Web-based respondent-driven sampling technique was used to recruit participants for the present study. Three hundred and thirty-two students and 130 teachers of varying ages and gender participated in the study. The link of web-based questionnaire was sent to respondents through WhatsApp/Facebook. Responses from all the participants were tabulated and analyzed using univariate analysis (Chi-square test).

RESULTS:

Prerecorded lectures (38.9%) and Webinar apps (35/8%) were the most common modules of online teaching by students. One-third (34.3%) had the convenience to attend lectures from home whereas 44.3% had difficulty in concentration. Commonly cited disadvantage by students was inability to do practical work (37.9%). Regarding teaching faculty, 43.8% had no prior knowledge of online teaching. Sixty percent of teachers had 4 h/week of online teaching. No face-to-face interaction (67.7%) and internet issues (26.9%) were commonly stated barriers by faculty.

CONCLUSION:

The pandemic has pushed the teachers and students toward newer teaching avenues. However, more needs to be done to supplement the existent teaching pattern and preparedness of teaching faculty by incorporating online assignments and assessment methods, strengthening digital infrastructure in medical schools, and training support for teachers.
The epidemiologic factors associated with breast density
Authors: Ye Dong-Man , Yu Tao
Published: July 2022

In recent years, some studies have evaluated the epidemiologic factors associated with breast density. However, the variant and inconsistent results exist. In addition, breast density has been proved to be a significant risk factor associated with breast cancer. Our review summarized the published studies and emphasized the crucial factors including epidemiological factors associated with breast density. In addition, we also discussed the potential reasons for the discrepant results with risk factors. To decrease the incidence and mortality rates for breast cancer, in clinical practice, breast density should be included for clinical risk models in addition to epidemiological factors, and physicians should get more concentrate on those women with risk factors and provide risk-based breast cancer screening regimens.
The complexity of higher Chow groups
Authors: Da Silva Genival , Lewis James D.
Published: July 2022

Let
$X/{\mathbb C}$
be a smooth projective variety. We consider two integral invariants, one of which is the level of the Hodge cohomology algebra
$H^*(X,{\mathbb C})$
and the other involving the complexity of the higher Chow groups
${\mathrm {CH}}^*(X,m;{\mathbb Q})$
for
$m\geq 0$
. We conjecture that these two invariants are the same and accordingly provide some strong evidence in support of this.
The Effects of Bisphenol A on Oxidative Stress, Antioxidant Defence, Histopathological Alterations and Lysozyme Activity in Narrow-Clawed Crayfish (Pontastacus leptodactylus)
Authors: Diler Öznur , Özil Öznur , Nane Ikbal Demet , Naziroglu Mevlut , Minaz Mert , Aslankoc Rahime , Ozmen Ozlem , Atsatan Kamil
Published: July 2022

This study aimed to investigate of bisphenol A (BPA) on histopathological tissue (hepatopancreas and gills), immune ability (lysozyme activity), oxidative stress and antioxidant defence in crayfish (Pontastacus leptodactylus). Crayfish were exposed to BPA to various concentrations (0 (control), and 10, 50, 100 μg/L) for 5 and 20 days in triplicates. Histopathological findings showed moderate to severe hyperemia and inflammatory cell infiltrations, irregular epithelial cell arrangements, degeneration, necrosis and sloughing at the cells, collapse of the hepatopancreas tubules and hyperemia, oedema and sloughing at the epithelial cells of gills. In addition to swelling of gills, accumulation of hemocytes in the hemocoelic space of the gill lamellae relating to dosage were noticed. Antioxidant-related enzyme activities which superoxide dismutase (SOD), Glutathione-S-transferase GST, and glutathione reductase (GR) activity in 10, 50, 100 μg/L BPA group were significantly lower than control at 5 days (p<0.05). Lysozyme activity (LSZ) was no significantly enhanced according to control (p>0.05). These results suggest that the alterations in the antioxidant enzymes and the histological structure of the hepatopancreas, and gill tissue of crayfish can be used as potential biomarkers for risk assessment in aquatic ecosystem.
En los límites y horizontes de la traducción del texto poético entre lenguas afines: Alda Merini, estudio de caso
Authors: Martínez Víctor Anguita
Published: July 2022

On the Limits and Horizons of Translation of Poetic Texts Between Cognate Languages: Alda Merini. A Case Study

The present study concentrates on the translation between cognated languages of the poetic genre with a contrastive approach. In order to demonstrate the degree of influence between languages when trasferring interlinguistically a poem, we will rely on the contributions of translation theorits to explain the process of transfer. For our purpose, we have selected two poems from La Terra Santa (1984) by Alda Merini, focused on her personal experience inside the psychiatric institution. We will reconstruct the peculiarities of her biography to get into the personal content hidden in her rhetoric in order to understand the original text and thus recreate it in the target language.
Chaplaincy, Mission and Elite Sport: A Cross-National Study of the Work of Chaplains in the National Football League (NFL) And English Premier League (EPL).
Authors:   , Whitmore William
Published: July 2022

Background: Sports chaplaincy is an established form of chaplaincy and ministry. However, little research has been conducted on the work of sports chaplains. Of the completed research, none has compared sports chaplaincy in different countries. Aim and methods: The aim of the present study is to compare and contrast the role and function of sports chaplains within American football’s National Football League (NFL) and the English Premier League (EPL) by way of qualitative empirical investigation. The study sought to understand the roles and skills of the sports chaplain, the governance and safeguarding structures chaplain’s operate within, and the missiological approach to this form of ministry. To investigate these elements, a qualitive approach was utilized. Data was collected via semi-structured interviews, participant observations and e-mail. Eight chaplains, four from each league, participated in the study, as well as two para-church organization leaders, from the US and UK respectively. The results showed that sports chaplains fulfilled roles comparable to chaplains within other sectors of chaplaincy, such as offering pastoral care and spiritual support. However, their work was contextual, in that how their roles were utilized differed between host organizations. Overall, chaplains felt marginalized in their work, but this position also allowed chaplains to provide support during times of challenge. Furthermore, the study demonstrated that accountability and evaluation mechanisms for sports chaplains were not consistent and safeguarding mechanisms for NFL chaplains were nonexistent. Finally, chaplains consistently expressed a calling to this form of ministry and felt that their work was a witness to the love and message of Jesus Christ. Conclusions: In the high-pressure, results oriented industry of elite sports settings, sports chaplains witness to the love of God and affirm the value of the individual, regardless of their performance or on-field results. In this, they witness to the missio Dei present in elite sport.
A First-Order Complete Temporal Logic for Structured Context-Free Languages
Authors: Chiari Michele , Mandrioli Dino , Pradella Matteo
Published: July 2022

The problem of model checking procedural programs has fostered much research
towards the definition of temporal logics for reasoning on context-free
structures. The most notable of such results are temporal logics on Nested
Words, such as CaRet and NWTL. Recently, the logic OPTL was introduced, based
on the class of Operator Precedence Languages (OPLs), more powerful than Nested
Words. We define the new OPL-based logic POTL and prove its FO-completeness.
POTL improves on NWTL by enabling the formulation of requirements involving
pre/post-conditions, stack inspection, and others in the presence of
exception-like constructs. It improves on OPTL too, which instead we show not
to be FO-complete; it also allows to express more easily stack inspection and
function-local properties. In a companion paper we report a model checking
procedure for POTL and experimental results based on a prototype tool developed
therefor. For completeness a short summary of this complementary result is
provided in this paper too.
Timed Automata Robustness Analysis via Model Checking
Authors: Bendík Jaroslav , Sencan Ahmet , Gol Ebru Aydin , Černá Ivana
Published: July 2022

Timed automata (TA) have been widely adopted as a suitable formalism to model
time-critical systems. Furthermore, contemporary model-checking tools allow the
designer to check whether a TA complies with a system specification. However,
the exact timing constants are often uncertain during the design phase.
Consequently, the designer is often able to build a TA with a correct
structure, however, the timing constants need to be tuned to satisfy the
specification. Moreover, even if the TA initially satisfies the specification,
it can be the case that just a slight perturbation during the implementation
causes a violation of the specification. Unfortunately, model-checking tools
are usually not able to provide any reasonable guidance on how to fix the model
in such situations. In this paper, we propose several concepts and techniques
to cope with the above mentioned design phase issues when dealing with
reachability and safety specifications.
Computability of Data-Word Transductions over Different Data Domains
Authors: Exibard Léo , Filiot Emmanuel , Lhote Nathan , Reynier Pierre-Alain
Published: July 2022

In this paper, we investigate the problem of synthesizing computable
functions of infinite words over an infinite alphabet (data $\omega$-words).
The notion of computability is defined through Turing machines with infinite
inputs which can produce the corresponding infinite outputs in the limit. We
use non-deterministic transducers equipped with registers, an extension of
register automata with outputs, to describe specifications. Being
non-deterministic, such transducers may not define functions but more generally
relations of data $\omega$-words. In order to increase the expressive power of
these machines, we even allow guessing of arbitrary data values when updating
their registers.
For functions over data $\omega$-words, we identify a sufficient condition
(the possibility of determining the next letter to be outputted, which we call
next letter problem) under which computability (resp. uniform computability)
and continuity (resp. uniform continuity) coincide.
We focus on two kinds of data domains: first, the general setting of
oligomorphic data, which encompasses any data domain with equality, as well as
the setting of rational numbers with linear order; and second, the set of
natural numbers equipped with linear order. For both settings, we prove that
functionality, i.e. determining whether the relation recognized by the
transducer is actually a function, is decidable. We also show that the
so-called next letter problem is decidable, yielding equivalence between
(uniform) continuity and (uniform) computability. Last, we provide
characterizations of (uniform) continuity, which allow us to prove that these
notions, and thus also (uniform) computability, are decidable. We even show
that all these decision problems are PSpace-complete for $(\mathbb{N},<)$ and
for a large class of oligomorphic data domains, including for instance
$(\mathbb{Q},<)$.
Regression Analysis with Scikit-Learn (part 1 - Linear)
Authors: Lavin Matthew J.
Published: July 2022

This lesson is the first of a two-part lesson focusing on an indispensable set of data analysis methods, logistic and linear regression. It provides an overview of linear regression and walks through running both algorithms in Python (using scikit-learn). The lesson also discusses interpreting the results of a regression model and some common pitfalls to avoid.
La historia como dimensión del presente
Authors: Padilla Moreno Juan
Published: July 2022

El artículo ofrece un conjunto de reflexiones que tienen por objeto mostrar que el pasado, y en particular el pasado histórico, no es sino una dimensión del presente; lo cual no implica, en opinión del autor, “presentismo”, en tanto que el pasado existiría en el presente como dimensión específica, irreductible a la mera actualidad del momento.
Desacuerdos cuidados
Authors: Almagro Manuel , Villanueva Neftalí
Published: July 2022

El pensamiento crítico parece ser la piedra de toque de la relevancia de la filosofía, aquello que nos permite mejorar nuestro modo de razonar. El propósito de este artículo es desarrollar una opinión extraordinariamente poco popular que nos parece, sin embargo, obviamente verdadera: El pensamiento crítico no es patrimonio exclusivo de la filosofía; probablemente ni siquiera es la filosofía la disciplina de la que cabe esperarse la contribución más crucial al desarrollo del pensamiento crítico. Sin embargo, la tesis principal de este trabajo no es negativa. Por el contrario, argumentamos aquí que hay ámbitos en los que la filosofía hace contribuciones genuinas y cruciales para el desarrollo del pensamiento crítico. El ejemplo que nosotros exploramos pertenece al ámbito del desacuerdo y del pensamiento conjunto. Para ello, proponemos pasar de una perspectiva exclusivamente individualista del pensamiento crítico a una perspectiva que incluya también la interacción con otros. La filosofía, defendemos, aporta herramientas útiles para pensar con otros, para que nuestros desacuerdos sean fructíferos, “cuidados”. En este sentido, como en otros, la filosofía sí contribuye al desarrollo del pensamiento crítico. El alcance de esta contribución, pensamos, solo puede verse cuando se presta atención a los detalles.
COMPARATIVE ANALYSIS OF THE PHYTOCHEMICAL CONTENT AND DESTRUCTIVE DISTILLATION OF BIOMASS CONSTITUENTS OF TWELVE TROPICAL TIMBERS IN SOUTH-EAST NIGERIA
Authors: Ejikeme Ezechi C. , Nwanisobi G.C , Okeke C. U
Published: July 2022

Twelve tropical timbers indigenous to the south-east of Nigeria were analysed for their physical properties with results as follows: pH 4.26-6.72, specific gravity (0.16-0.49), charring temperature (64 -116oC) and porosity index (1.08 - 2.24%). Results of quantitative and proximate analysis of the constituent of woods studied includes; tannin (760 mg/100 g - 1240 mg/100 g), alkaloids (4.0-14.6%), flavonoids (2.0 -10.5%), saponin (2.0 - 11%), oxalate (0.28 - 2.92 g/100 g), total acidity (0.09 -0.54 g/100 cm3), cyanogenic glucoside (324-891 mg/100g), moisture content (13-31%), lipid (0.8-7.6%) and ash content (1.0-3.5%,). The qualitative screening was carried out to determine the presence of metabolites in the wood sample. Also, the destructive distillations of the timbers were studied. Results revealed their compositions as follows; wood charcoal (1.50 to 5.00 g), pyroligneous acid (2.0 -3.0 cm3), wood tar (0.1- 0.3 cm3) and wood gas (512 cm3 - 998 cm3). Thus, from the qualitative and quantitative analysis, it was observed that the timbers have medicinal properties which could be harnessed by pharmaceutical industries in drug formation or production while the products obtain from the destructive distillation of the wood can be utilized by other industries for industrial process.
SELECTED HEAVY METAL CONTENT OF ANAMBRA-GROWN OIL PALM BUNCH ASH (NGU): HUMAN HEALTH RISK ASSESSMENT.
Authors: Nwoka N. G . , Asomugha R. N. , Igwe C. U.
Published: July 2022

Edibles can be contaminated by heavy metals as described in various patents. The study determined the potential human health risk associated with the consumption of palm bunch ash (PBA) from Anambra State, Nigeria. Concentrations of Cd, Pb, Hg and Zn were determined using Atomic Absorption Spectrophotometer (AAS). Human health risk assessment employed Estimated Daily Intake (EDI), Target Hazard Quotient (THQ), Hazard Index (HI), and Carcinogenic Risk. The EDI values (5.14x10-6 – 5.22x10-4, 9.97x10-5 – 1.23x10-3, 4.14x10-7 – 5.91x10-4, 4.29x10- 7 – 1.36x10-2) mg/kg/day and the THQ values were (9.43x10-3 -5.22x10-1, 7.84x10-4 – 0.586, 5.86x10-3 – 3.83, 1.43x10-6 – 3.90x10-1) for Cd, Pb, Hg and Zn respectively. There was a violation of permissible Tolerable Daily Intakes (PTDI) set by JECFA. Hazard indices of some samples were more than 1, another indication of health concern. The mean concentration of metals in PBA ranged from 0.0041 - 95.012mg/kg. When compared with standards by WHO, EU and USEPA, violation was observed in Cd, Pb and Hg. Cadmium showed very high carcinogenic risk with values of 3.18 x10-3mg/kg/day. Consumption of palm ash from Anambra State Nigeria may pose significant health risk.
PHYTOCHEMICAL AND GC-MS ANALYSIS OF BIOACTIVE COMPONENTS IN ETHANOLIC EXTRACT OF Rauvolfia vomitoria LEAVES
Authors: Ajayi O. A.
Published: July 2022

Herbal medicine has demonstrated great potential of therapeutic benefits in its contribution to modern medicine. Africa is endowed with many plants that can be used for medicinal purposes to which they have taken full advantage. Rauvolfia vomitoria is one of the medicinal plants that is widely distributed across the forests of Africa and Asia. Phytochemical analysis of ethanolic extract of Rauvolfia vomitoria leaves was carried out. The result indicated the presence of Tannins, Saponins, Steroids, Glycosides, Alkaloids, and Flavonoids. Further analysis of the Ethanolic extract of Rauvolfia vomitoria leaves was carried out using GC-MS. Among many compounds determined in the GC-MS analysis of the leaves extract were Methenamine, Benzofuran and Methyl urinate which have been reported to be anti-inflammatory, anti-oxidant, anti-fungal and anti-bacterial. The Ethanolic leave extract of Rauvolfia vomitoria therefore could contribute immensely to effective treatment of some infectious diseases.
PHYTOCHEMICAL SCREENING AND EVALUATION OF ANTIOXIDANT ACTIVITIES OF THE STEM AND LEAVES EXTRACT OF Phyllanthus niruri OBTAINED FROM ADAMAWA STATE, NIGERIA.
Authors: Gaila N.M , Ahmed Aisha , Omar A. W
Published: July 2022

Phyllanthus are genus of a flowering plants used in herbal medicine. Commonly used in Ayurvedic healing, Phyllanthus niruri (P. niruri) known as “STONE BREAKER” are one of the herbal medicinal plants that has a broad range of properties, which are antiviral activities against hepatitis B, antimicrobial, hepatoprotective, anticancer, and hypocalcemic agent. This research were conducted to screen the phytochemical composition, evaluate the antioxidant assay using trolox and gallic acid is control and to determine the antioxidant content of P. niruri extract using rutin and quercetin as standard, which are flavonoids possessing medicinal properties. The qualitative phytochemical screening assay on P. niruri extract showed that the extract had a high content of saponins (+++), a moderate content of phenols, flavonoids, and tannins (++). It also had a low content of steroids, but triterpenoids, terpenoids, and alkaloids were not detected in the screening (-). Rutin and quercetin contents of the crude extracts were determined using high performance liquid chromatography (HPLC) and the antioxidant activity assay were measured using UV-Spectroscopy by 1, 1-diphenyl-2-picryl-hydroxyl (DPPH) method. The result show that the concentrations of quercetin and rutin in the sample analyzed were 185.96±0.5 and 91.68±0.21 µg/g respectively while the DPPH IC50 values of the crude extract were 62.05 µg/ML. The significant amounts of these antioxidants confirm the nutritional and medicinal value of the plants sample.
EVALUATION OF POLYCHLORINATED BIPHENYL (PCB) COMPONENTS OF BEANS CONSUMED IN GOMBE METROPOLIS NIGERIA
Authors: Usman Y. M. , Danbature W. L. , Zaliha A. Y.
Published: July 2022

Pesticide residues in beans circulating as food commodities in the national markets have been characterized as an environmental hazard due to its persistence and toxicity to both wildlife and humans. Researchers have to enact tactful methods to minimize their harmful residues effects in food in order to protect the consumers. This study investigated the pesticides residues concentrations of Polychlorinated Biphenyl (PCB) components in beans in relation to their recommended values using GC- MS analysis. The results showed that three different samples B2, B3, and B4 contained pesticide residue concentrations within the maximum recommended levels (MRLs) of 0.01 mg/kg to 0.2 mg/kg, while two samples B1 and B5 showed concentrations of pesticide residue beyond maximum recommended residue levels exhibited by 2,2’,4,5,5’,-Pentachlorobiphenyl showed concentration of 1.17518 ppm, and 2,2',3,4',5,5',6-Heptachlorobiphenyl showed concentrations of 0.4599 ppm respectively. Moreover, the percentage protein content of the beans samples investigated showed a decreasing order as B5 = 2.09 % > B4 = 1.96 % > B3 = 1.96 % > B2 = 1.95 % > B1= 1.8 % thus, B1 and B5 samples of beans are unsafe for continuous consumption but B5 showed highest protein content than other samples.
QUANTITATIVE EVALUATION OF ALKALOIDS, FLAVONOIDS, SAPONINS, STEROIDS AND TANNINS CONTENTS FROM THE SUCCESSIVE SOLVENT EXTRACTS OF Crinum zeylanicum Bulb.
Authors: Daben J.M. , Dashak D.A. , Lohdip A.M.
Published: July 2022

Crinum zeylanicum (L.) of the family Amaryllidaceae is one of the medicinal plants that have gained ancient-to-date popularity in the healing of skin diseases, bone fracture and other tropical illnesses in traditional medicine practices. The grounded bulb was extracted successively using n-hexane, ethyl acetate, methanol and water. The raw sample and the successive extracts were evaluated for alkaloids, flavonoids, saponins, steroids and tannins contents using specific standard gravimetric methods for each component. Correlation analysis of the components was also carried out. The quantitative determinations revealed the range of the bio-components as saponins (37.20-13.08%,), alkaloids (22.14-4.62%), Tannins (19.47-2.79%), Flavonoids (15.32-0.08%) and Steroids (10.49-0.72). The correlation coefficient analysis at 5% identified high negative correlation between saponins and steroids at (-0.921) as the most significant value (p=0.026), likewise alkaloids and saponins, alkaloids and tannins, flavonoids and saponins, flavonoids and tannins, steroids and tannins but statistically insignificant. It however, revealed high positive correlation of alkaloids and steroids (+0.872) at insignificant value (p=0.055) and such other correlations in this study are alkaloids and flavonoids, flavonoids and steroids, saponins and tannins. At 95% confidence interval of the differences in the paired components, showed that alkaloids and steroids, flavonoids and saponins, saponins and steroids, saponins and tannins are statistically significant (p=0.009- 0.012) while others are insignificant (p-0.057-0.978). These results indicated that the bulb contained essential medicinal components suitable for health benefits and considered a multifaceted plant for curing many types of diseases and illnesses.
SUB-CHRONIC INTERACTION OF SELENITE AND ARSENITE CAUSES DYSLIPIDEMIA IN MALE WISTAR RATS
Authors: Adeyi O. E. , Adeyi O. A. , Ayodeji A. H. , Moses C. A.
Published: July 2022

Arsenic (As) an environmental toxicant constitutes a serious hazard to human health while selenium (Se), although a trace element recognized for its protective properties can be toxic depending on its chemical form and dose administered. This present study investigated the effects of co-exposure to As in form of sodium arsenite (As III) and Se as sodium selenite (Se IV) on the lipid profile of male albino rats. Thirty animals were divided into six; group I (control) received distilled water; groups 2 and 3 were exposed to 20 and 40 ppm arsenic as sodium arsenite respectively; in addition to 20 and 40 ppm arsenite, groups 4 and 5 were also administered 0.25 mg/kg b.wt selenite while group 6 was exposed to only 0.25 mg/kg/ b.wt selenite for five weeks. Hepatic, renal and splenic cholesterol (CHOL) concentrations increased significantly in animals co-exposed to 40 ppm (the higher As dose) + 0.25 mg/kg b.wt Se while a reduced CHOL resulted with the lower dose except in the lungs when compared to the control. Similarly, while an increased hepatic, splenic and plasma triacylglycerol (TAG) concentrations ensued on co-exposure to the higher dose, there was no significant (p>0.05) difference on co-exposure to the lower dose except in the plasma where a 24 % decrease was observed. The lipoproteins (HDL-CHOL and HDL-TAG) decreased significantly (p < 0.05) in groups exposed to only As whereas LDL+VLDL concentrations of both CHOL and TAG increased in co-exposed groups in a dose-dependent manner. This study revealed the dyslipidemic potential of the sub-chronic exposure to both arsenite and selenite in male wistar rats.
KINETIC AND THERMODYNAMIC STUDIES OF REMOVAL OF 2-NITROPHENOL FROM AQUEOUS SOLUTION USING COWPEA HUSK POWDER TETHERED ON IRON OXIDE.
Authors: Adeniji A. E. , Osundiran F. J. , Ayoola O. G. , Adeogun A.I. , Adeogun A.I. , Idowu M.A.
Published: July 2022

The uptake of 2-nitrophenol (2NP) from aqueous solution onto cowpea husk powder tethered on iron oxide (CHPI) and pristine cowpea husk powder (CHP) for comparison was investigated under different experimental conditions such as, initial adsorbate concentration, adsorbent dose, contact time, solution pH and temperature using UV-Visible spectrophotometer. Adsorption isotherms were described using the Langmuir and Freundlich models. The experimental data fitted into Freundlich isotherm equation, indicating monolayer adsorption of the adsorbate on the surface of the adsorbent. Kinetic evaluations showed that the adsorption mechanism of the iron tethered cowpea husk powder was well described by the Lagergren pseudo-first-order model with rate constant increasing with initial adsorbate concentration and evaluated to be 9.4x10-3 g·mg−1·min−1 for CHPI and 1.67x10-2 g·mg−1·min−1 for CHP respectively; showing the iron tethered cowpea husk powder as a better adsorbent. The evaluations of enthalpy, entropy and free energy changes revealed that the adsorption processes were spontaneous and endothermic in nature. The study revealed that both adsorbents studied behaved considerably well with an added advantage of convenient adsorbent separation with use of the iron tethered cowpea husk powder.
SEASONAL VARIATION IN TRACE METAL CONCENTRATIONS IN SOIL AND VEGETABLE SAMPLES FROM SELECTED MINING AREAS IN JOS SOUTH AND BARKIN LADI LGA, PLATEAU STATE
Authors: Gungshik J. R. , Salami S. J. , Gushit J. S. , Eseyin A. E , Ibrahim M.
Published: July 2022

In this study, the seasonal variation in concentrations of the trace metals Cu, Zn, Pb, Cd, As Ni and Co in soil and vegetable samples from farms in some mining areas in Jos South and Barkin Ladi LGA, Plateau State were investigated in two major seasons (dry and wet). This was done to assess the pollution status of the farms and hence, the safety levels of the vegetable samples. The samples were treated and digested using 10 cm3 HNO3 and 30 cm3 HCl in the ratio of 1:3. Trace metal concentrations were determined using the PG-990 model atomic absorption spectrophotometer. Analytical results of soil samples from mining areas indicated higher concentration of Cu and As for both seasons than the values reported by the FAO/WHO (2007). Similarly, the metals Cu (15.12±1.50 mg/kg), Zn (76.45±2.40 mg/kg), Pb (23.75±1.35 mg/kg), Cd (3.69±0.15 mg/kg), Ni (17.80 ±0.15 mg/kg) and Co (28.14+1.35 mg/kg) showed high concentrations in dry season than wet season. Comparing the vegetable samples, spinach was found to accumulate high concentration of trace metals than tomato and Irish potato. In general, the levels of trace metals in soil and vegetable samples were higher in dry season than in wet season. The levels of Pb, Cd, As, Ni and Co were significantly above the critical toxic level in vegetables as reported by WHO/FAO (2007), while Zn and Cu occurred within the acceptable limit for both seasons.