bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental Analysis of the Degradation of PV UDTS-50 W Modules Exposed to Extreme Weather Conditions in a Saharan Environment
Authors: Slimane Laribi , Touhami Ghaitaoui , Zohra Arama Fatima , Touahri Tahar
Published: February 2022

The degradation of the electrical performance of photovoltaic modules UDTS-50W exposed to the sun for a long period of about 10 years in a Saharan environment of Adrar was presented. In this article, the experimental results obtained during the analysis of the I-V characteristics of some UDTS-50W photovoltaic modules tested in the real conditions of the Saharan environment (Adrar region). The electrical performance degradation of the UDTS-50 W PV modules was identified by empirically analyzing the I-V and P-V characteristics and by visual field inspection of these modules, which were installed in a renewable research unit in a desert environment (URERMS). The comparison between the experimental characteristic curves IV and PV of the PV modules UDTS-50W and the reference in the standard test conditions (STC) shows that the degradation of the electrical performances is due globally by the delamination and the discoloration of the Ethylene-vinyl acetate (EVA) encapsulate after the long term exposure in a desert environment.
Improving Productivity of Misaligned Boring of Hydraulic Cylinder Holes with a Rotating Cutter Block Based on Computer Simulation Results
Authors: Tolmacheva Tatyana A. , Kuts Vadim V. , Malneva Yuliya A.
Published: February 2022

The analysis of existing processing methods was carried out. A series of virtual experiments was performed; based on their results dependences of the height of residual ridges, the temperature on the workpiece surface and the temperature in the cutting zone on the parameters of the processing mode when boring internal holes with a rotating cutter block were constructed based on the results of virtual computer simulation. An optimization model of the boring process was built. The objective function was received. Within the optimization model framework, solutions were obtained that allow, at the highest value of axial feed, to ensure the required surface quality and avoid changes in the physical and mechanical properties of the material.
Quality Assurance for the Appearance of Paint Coatings
Authors: Loganina Valentina I. , Zaytseva Maria V. , Fokin Georgy A.
Published: February 2022

The article provides information on the application of statistical methods of product quality management to the analysis of the process of obtaining paint and varnish coatings with desired properties. A correlation has been established between the standard deviations of the roughness indicators of the coating surface and the surface to be painted. The relationship between the standard deviations for the surface roughness of the coatings and the surface to be painted is given. The results of calculating the values of the root-mean-square deviation of the roughness of the coatings and the class of roughness of the substrate surface, providing with a probability of 0.95 a given class of roughness of the coating surface. The calculation results make it possible to choose a more optimal staining mode in order to obtain a smaller spread in the roughness index of the formed coating. This provides a guaranteed level of quality for the painted surface.
Study of Ageing Processes of a Nickel Superalloy under Conditions of High-Temperature Loadings
Authors: Berdnik Olga , Krivina Liudmila , Kirikov Sergey , Tsareva Irina
Published: February 2022

The results of studies of microstructure and of mechanical properties of the superalloy Udimet 720 in initial and aged states at various temperatures (850 °С, 1000 °С и 1200 °С) are presented in the paper. Mathematical processing methods were used during the analysis of morphological and geometric characteristics of strengthening phases in the alloy. Dependencies of mechanical properties indices on parameters of strengthening phases of the microstructure have been revealed. It has been found that the downtrend of strength and plastic characteristics of the alloy that was aged at high temperatures is due to changes in morphology and content of intermetallic phase.
Sequential Treatment of Steel Surfaces by Nitriding and Ultrasonic Hardening
Authors: Sundukov Sergey K. , Nigmetzyanov Ravil I. , Prikhodko Vyacheslav , Fatyukhin Dmitriy
Published: February 2022

One of the ways to develop existing methods of hardening is creation of hybrid technologies that combine the principles of chemical heat treatment and surface plastic deformation. This paper proposes a nitriding technology followed by ultrasonic treatment. As a result of such sequence, a surface layer is formed that has an increased hardness and depth of hardening, in comparison with combined methods used separately.
Analysis of Factors Affecting Operability to Assess Risks and Opportunities in the Operation of Built-Up Cutting Tools
Authors: Artamonov Evgeniy , Vasilega Natalya , Yadygin Andre
Published: February 2022

Adaptation of the previously developed methodology for assessing risks and opportunities for assessing risk situations and identifying opportunities during operation of built-up cutting tools is made. The factors influencing performance of built-up cutting tools are analyzed. The article presents an analysis of failures of replaceable inserts of built-up cutting tools when performing face milling operations, the results of which will be taken into account when applying the developed technique.
Influence of Various Production and Processing Methods on the Structure and Properties of Porous Titanium Coatings
Authors: Skvortsova Svetlana V. , Ivanov Alexey E. , Lidzhiev Arslang A. , Ruchina Natalia V.
Published: February 2022

A comparison was made of the properties of porous coatings obtained by ion-plasma spraying methods, 3D-coating obtained by direct laser metal deposition (DLMD), as well as a GRIPTION® and POROCOAT® coating. The influence of various methods of obtaining a porous coating on the porosity and structure of the coating, as well as the effect of thermal hydrogen treatment (THT) on the adhesion strength of the titanium coating was determined.
The Peculiar Properties of Economically Effective Technology of Forming of the Ceramic Coating Based on Aluminum Oxide
Authors: Bolotov Alexander N. , Novikov Vladislav V. , Novikova Olga O.
Published: February 2022

Increasing of the hardness and wear resistance of the working surfaces of parts made of aluminum and its alloys is achieved by modifying them by the method of micro-arc oxidation in alkalescent electrolytes. This technology consists in the formation of a highly hard and wear-resistant ceramic layer by means of the spark discharges and implies an enormous investment of energy and time. The finished product surface roughness in numerous cases fails to meet the requirements, and demands additional machining. High hardness of the hardened layer, at the same time causes an increased wear of the processing tool. A method in which the technological process is carried out in two stages allows improving energy efficiency of this technology. At the beginning, when using an electrolyte with a high content of liquid glass, a primary oxide layer, consisting predominantly of silicon oxide, is formed. At the next stage of micro arc oxidation, the content of the liquid glass in the electrolyte decreases, which allows the formation of predominantly high rigid aluminum oxide in ceramic layer. This technology can significantly reduce the time of formation of a coating and reduces energy consumption. To reduce the processing tool wear it is proposed to keep the surface of the modified by oxidation workpiece in hydrofluoric acid for 5 - 30 minutes. This operation allows to reduce the hardness of the upper layer, consisting mainly of silicates, without affecting the lower layer, formed mainly of aluminum oxide. As a result, it is possible to receive the required surface micro geometry with less tools wear, less time and energy. There was achieved a reduction of time for getting the finished product by 1.6 - 2.3 times, electricity by 2 - 2.7 times, tool wear by 8.7 - 12 times.
Decompensated chronic liver disease
Authors: Bhavsar Ruchir , Ray Samrat , Nundy Samiran
Published: February 2022

Decompensated chronic liver disease is the 14th leading cause of mortality in adults. It includes many aetiologies, some of which are treatable and preventable, whereas others are not. It is a progressive disease, resulting in various manifestations such as portal hypertension, hepatorenal syndrome, portopulmonary hypertension, ascites, spontaneous bacterial peritonitis (SBP), variceal bleeding and cardiomyopathy, which unless treated, result in end-stage liver failure requiring liver transplantation as treatment. In the present article, we review its aetiopathogenesis, clinical features and the current guidelines recommended for its treatment from a high volume tertiary care centre in India.
Helminthic infections among primary school children in Gboko, Benue State, Nigeria
Authors: Njoba Francis Chinasa , Ekejindu Ifeoma M. , Ezeagwuna Dorothy Amauche , Nnamani Chioma Phyllis
Published: February 2022

Introduction:

Helminthic infection (HI) is one of the neglected tropical diseases that affect the poorest and most deprived communities, affecting individuals of all ages. The study aimed to determine the prevalence and predisposing factors of HIs among primary schoolchildren in the rural and urban communities of Gboko, Benue State, Nigeria.

Materials and Methods:

It is a cross-sectional survey of 414 randomly selected pupils from six primary schools. Stool samples collected were processed using formol–ether concentration method. Pretested, interviewer-administered semi-structured questionnaires were used to assess for relationship between infection and factors that significantly contribute to the transmission of HIs. Soil samples were also collected from different locations of the selected schools.

Results:

The overall prevalence of HIs was 45.4%. Hookworm was the most encountered parasite (57.4%); there were also mixed infections of Ascaris lumbricoides and hookworm (8.5%) and hookworm and Trichuris trichiura (1.6%). The prevalence was more in males (46.7%), pupils aged 14–16 years (47.1%) and pupils residing in rural area (49.3%). There was significant relationship between age and hygienic practices of the pupils with HIs (P = 0.00 and 0.002, respectively). There was also significant relationship between marital status, educational level of caregivers and occupation of household heads of the pupils and HIs (P = 0.00, 0.00 and 0.00, respectively).

Conclusion:

The presence of viable HIs eggs/larvae in the soil suggests possible active transmission and high rate of exposure to infective agents among the schoolchildren. There is need for organised and routine deworming exercises among schoolchildren in the affected communities and also aggressive health education on the risk associated with HIs in the environment.
Duodenal atresia with bile-duct anomaly
Authors: Ankur Kumar , Prasad Aparna , Jain Prashant , Prasad Ashish , Chetry Sanjeev
Published: February 2022

A full-term female infant is born via vaginal delivery to a 26-year-old primigravida with unexplained polyhydramnios and antenatal diagnosis of duodenal atresia. After birth, bilious fluid was aspirated through the orogastric tube and the initial abdominal radiograph was suggestive of double bubble sign with the absence of air in the distal bowel. Baby passed meconium at 4 h of life and repeat abdominal radiograph showed double bubble sign with the presence of air in distal bowel. Upper gastrointestinal contrast study done revealed distension of the stomach and duodenal bulb with an abrupt narrowing. It also revealed flow of contrast into the jejunal loops on the right side of the spine which was suggestive of intestinal malrotation as the leading diagnosis. However, intra-operative findings confirmed a Type III Duodenal atresia with bile proximal and distal to atretic. Occasionally, distal bowel gases can be seen in radiographs of infants with duodenal atresia due to abnormal development of the biliary system that can allow passage of air from the proximal duodenal segment to the distal. Here, we report a case and discuss the embryology of this rare entity.
Sway amplitude during foam and dome test in typical young adults
Authors: Shivanna Gowda Preethi H. , Samuel Raj Vijay V , Mishra Siddarath S.
Published: February 2022

INTRODUCTION:

Balance is one of the most important components for an individual to be in a good state of health condition. The functional balance is most important for the individual to maintain the equilibrium, and the characteristics of the task may increase or decrease the difficulty of the balance component. There is a need to obtain normative sway variabilities (angle, distance, and frequency) in different planes among young adults, which may be used in clinical and sports for balance evaluation and training.

MATERIALS AND METHODS:

Repetitive measure design was used to identify the normative values of foam and dome test on the typical young adults. The sway variabilities of the typical young adults were evaluated through standardized foam and dome test. The anterior-posterior (AP) and mediolateral sway angle and distance were measured using Kinovea software at six phases on a postural grid and results were analyzed using range, mean, and standard deviation.

RESULTS:

Seventy-six participants, 50 females and 26 males were recruited (mean age 21.5 ± 15 years). The mean sway angle with eyes open (EO), eyes closed (EC), with dome, on foam with dome, on foam with EO, on foam with EC in AP plane was 4.15 ± 1.57, 8.09 ± 2.56, 10.47 ± 2.88, 18.42 ± 4.27, 9.15 ± 2.22, and 17.6 ± 5.38,°, respectively. The mean sway results were consistent in similarity with the angle, and frequency.

CONCLUSION:

The study concludes that the sway amplitude values obtained using foam and dome test showed that the angle, distance, and the number of sways increase with the alteration in the sensory input.
Increasing motivation for cancer treatment adherence in children through a mobile educational game: a pilot study
Authors: Chai Wang Er Carmen , Bee Theng Lau , Tee Kit Tsun Mark , Al Mahmud Abdullah
Published: February 2022

INTRODUCTION: It is crucial to educate childhood cancer patients (CCPs) about their illness and motivate them for cancer treatment and treatment side-effects management.OBJECTIVES: This paper describes the design, development and pilot evaluation of the proposed serious game intervention with CCPs in Malaysia.METHODS: A single-centre, single-arm intervention was conducted with CCPs (n=8). Surveys were done pre-test and post-test.RESULTS: The Protection Motivation Theory was used to measure the participants' motivation. Self-reported surveys with CCPs and caregiver dyads showed a significant increase in participants’ intention to use cancer treatment. Although the increase in the intention to use daily self-care and cancer knowledge survey scores was not substantial, the post-test caregivers' feedback revealed that the game was beneficial for their children.CONCLUSION: Early results of the study have shown the intervention’s potential to boost the knowledge and motivations of CCPs.
RETORNO DAS AÇÕES E SENSIBILIDADE AO RISCO DE MERCADO DAS EMPRESAS PARTICIPANTES DO ÍNDICE CARBONO EFICIENTE (ICO2) DA B3 S.A.: UM ESTUDO COMPARATIVO
Authors: Souza André Luis , Da Silva Junior Antônio Francisco , Andrade José Célio , Fernandes Maria Eduarda
Published: February 2022

Essa pesquisa objetivou examinar qual a relação entre a participação das empresas no ICO2/B3 e o retorno e sensibilidade de suas ações ao risco de mercado visando subsidiar a tomada de decisão por parte de empresas e investidores. A motivação da pesquisa consiste em avaliar se empresas que decidem participar do ICO2 têm benefícios de maiores retornos e/ou menor risco de mercado, o que poderia induzir a decisão das firmas em aderirem ao ICO2 e influenciaria a decisão dos investidores em suas alocações de ativos. Para alcançar o objetivo proposto, realizaram-se dois estudos, denominados de estudo “a” e estudo “b”. No estudo “a” adotou-se técnicas estatísticas de regressão pelo modelo dos MQO e em painel com a finalidade de comparar o desempenho entre empresas que ingressaram no ICO2 (27) e empresas que não ingressaram (8). Já no estudo “b” utilizou-se de técnicas estatísticas de regressão SUR para análise dos retornos e riscos individuais, além de MQO e em painel, cuja análise focou-se no grupo de empresas que ingressou no ICO2 (27), para examinar o período pré e pós-admissão no índice. Os resultados evidenciaram que as empresas que ingressaram no ICO2 não apresentaram retornos das ações superiores em comparação ao grupo de empresas que não ingressou no ICO2, mas apresentaram menor sensibilidade ao risco de mercado do que o grupo de empresas que não ingressou no índice. Além disso, a análise focada apenas nas empresas que participavam do índice não evidenciou uma mudança de comportamento nos retornos e na sensibilidade ao risco de mercado das ações desse grupo de empresas após ingressarem no índice em comparação ao período que antecedeu a sua entrada na iniciativa. Assim, os resultados sugerem que empresas menos sensíveis ao risco de mercado são mais propensas à adesão ao ICO2 e essa adesão não necessariamente implica maiores retornos financeiros.
GERENCIAMENTO DE RESULTADOS EM COMPANHIAS DO SETOR DE CONSTRUÇÃO CIVIL: INFLUÊNCIA DA ADOÇÃO DO CPC 17
Authors: Baldissera Juliano Francisco , Gomes Adhmir Renan Voltolini , Zanchet Aládio , Fiirst Clovis
Published: February 2022

No Brasil, a convergência aos padrões contábeis internacionais afetou a realidade das empresas de construção civil, em virtude da adoção do Pronunciamento Técnico CPC 17 – Contratos de Construção, permitindo certa discricionariedade aos preparadores. Diante disso, o objetivo da pesquisa foi verificar o efeito da adoção do CPC 17 no gerenciamento de resultados das empresas brasileiras do setor de construção civil listada na B3 (Brasil Bolsa Balcão). Delineou-se esta pesquisa por meio de uma abordagem quantitativa, realizando-se um estudo empírico. A amostra foi composta pelas companhias brasileiras listadas na B3 do setor de construção civil, cujos dados foram coletados por meio da Economática® e da Comissão de Valores Mobiliários (CVM), para o período de 2007 a 2012. Aplicou-se o modelo desenvolvido por Kang e Sivaramakrishnan (1995) para estimar o gerenciamento de resultados. Os dados desta pesquisa demonstraram que no período analisado os níveis de gerenciamento de resultados das empresas do setor de construção civil são decrescentes. Além disso, observou-se que essas empresas gerenciam para baixo os seus resultados, demonstrando que as escolhas contábeis dos gestores não são somente para aumentar seus resultados. Os resultados permitiram concluir que existe diferença significativa nas práticas de gerenciamento antes e depois da vigência da norma, com uma influência negativa do CPC 17 nos níveis de gerenciamento de resultados das empresas. Como contribuição este artigo alerta sobre o possível aumento no gerenciamento de resultados decorrente da adoção do CPC 47 após o primeiro ano.
AVALIAÇÃO DO IMPACTO DOS INCENTIVOS FISCAIS SOBRE OS RETORNOS E AS POLÍTICAS DE INVESTIMENTO E FINANCIAMENTO DAS EMPRESAS
Authors: Rezende Amaury José , Dalmácio Flávia Zóboli , Rathke Alex Augusto Timm
Published: February 2022

Este artigo contribui para o debate sobre a relação entre incentivos fiscais (subvenções governamentais) e as políticas de geração e destinação de valor das empresas brasileiras, todavia, até então, poucas conclusões podiam ser extraídas da literatura, a respeito deste assunto, no contexto econômico e tributário brasileiro. Utilizando uma análise de dados em painel, numa amostra de 108 empresas listadas pelo IBRX-100 (324 observações), que compõem as 653 empresas cadastradas na Comissão de Valores Mobiliários, no período de 2011 a 2013. Usando a teoria de Pecking order, como lente teórica, foram identificadas evidências consistentes de que as políticas fiscais brasileiras representam uma forma de financiamento bastante recorrente, entre as empresas pesquisadas. Esses resultados, a priori, acrescentam um elemento novo à teoria, segundo a qual a principal fonte de financiamento das empresas era o lucro. Os resultados demonstram que os incentivos fiscais: (i) têm relação positiva com a geração de margens e o valor adicionado das empresas; (ii) impactam positivamente o fluxo de caixa das operações e de investimentos, no curto prazo; e (iii) possuem relação negativa com o fluxo de caixa de financiamento e com o índice de endividamento. Além disso, as empresas que mais remuneram seus acionistas são as que mais usufruem de incentivos fiscais. Por fim, os resultados revelam que os incentivos fiscais não alteram os indicadores de geração e destinação valor, no longo prazo.
On the distinction between Friedrich Hegel’s dialectics and the logic of conversational thinking
Authors: Ofuasia Emmanuel
Published: February 2022

Following the publication of Jonathan O. Chimakonam’s astounding book, Ezumezu: A System of Logic for African Philosophy and Studies, a monumental piece in the history of African philosophy and logic, which also undergirds the backbone of conversational thinking, various uncharitable misconceptions and misrepresentations have greeted the work. Of the several misrepresentations and misconceptions, the tendency to treat the logic as an African variant of Friedrich Hegel’s dialectics is common. Being a three-valued logic, the tendency to perceive the third value ‘e’ in conversational thinking as a synthesis is replete in several commentaries and criticisms. This has almost become the norm since Hegel’s third value, following thesis and anti-thesis signifies a synthesis. Through the method of philosophical analysis, I argue that: (1) the logic of conversational thinking is not similar to Hegel’s dialectics hence, all commentaries and criticisms in this guise exhibit the Strawman fallacy; (2) for the logic that underlies conversational thinking, synthesis is an anathema; and (3) conversational thinking places emphasis on complementarity over contradiction. Following these points, I submit that when the veil of Hegel is cast aside, a deeper appreciation for an Africa-inspired logic, which has the capacity to mediate thinking for Africa and beyond, may be discerned almost effortlessly.
Decolonising method in the age of transdisciplinarity: a case for conversational thinking
Authors: Negedu Isaiah Aduojo
Published: February 2022

I will respond to two queries in this work. The first bothers on the possibility of having a single space in a transdisciplinary discourse. What will scholarship look like when we all come from our various vantage points? The second issue is a corollary of the first; will transcendence of disciplines be another ploy of coloniality to create a special breed that privileges one group over others? Overall, I argue that transdisciplinarity, as it stands, is inadequate since it silently promotes the exclusion of some methods. I will call for conversational thinking, which serves as a model for others to speak meaningfully and be heard.
Evaluation of Physicochemical Characteristics and Carbonate Equilibria System of the New Calabar River, Choba, Rivers State, Nigeria
Authors: Ojobo K.C. , Adowei P.
Published: February 2022

Carbonate equilibrium helps to critically determine the degree or level of pollution and its possible source. In this study the physicochemical properties and carbonate equilibria system of the New Calabar River, Choba, Rivers State, Nigeria was evaluated using standard techniques by analyzing the pH, total dissolved solid, bicarbonate ion, sulphate ion, chloride ion, total alkalinity and total hardness of five samples collected from strategic points along the River. Data obtained show that the pH ranged 5.93-6.33, while TDS values varied from 4770mg/l to 5280mg/l. The total alkalinity of the sample 1, sample 2, sample 3, sample 4 and sample 5 analyzed and their results are 70mg/l, 68 mg/l, 66 mg/l, 73 mg/l and 60.5 mg/l respectively. The total hardness of sample 1, sample 2, sample 3, sample 4 and sample 5 collected from the New Calabar River and the results are 913mg/l, 904 mg/l, 942 mg/l, 933 mg/l and 939 mg/l. The sulphate ion concentration for sample 1, sample 2, sample 3, sample 4 and sample 5 are 519.20mg/l, 510.5mg/l, 552mg/l, 543mg/l and 549.00mg/l, while the Chloride concentration varied from 3390.5 mg/l to 4,802 mg/l mg/l. Result indicated that all physiochemical parameters apart from total alkalinity was not within the WHO guidelines or standard and the river shows presence of weak acid deposits but very high concentration of chloride ion which indicates higher degree of organic pollution and also acidic in nature. Thus, the river poses a health risk to the rural communities who rely primarily on them as the only source of domestic water supply.
Occurrences of Metalo-β-lactamase Producing Pseudomonas aeruginosa among Clinical Samples in Kwara state, Nigeria
Authors: Adekunle O.C. , Mustapha A. , Odewale G. , Ojedele R.O.
Published: February 2022

Pseudomonas aeruginosa is a frequent nosocomial pathogen that causes severe disease in many clinical and community settings. The objective of this paper was to isolate Pseudomonas aeruginosa from clinical samples and to investigate the occurrence of metallo β- lactamase enzyme production by collecting 145 males and 90 females’ human clinical specimens from five selected health institutions within Kwara state, Nigeria. The samples were cultured immediately using standard microbiological procedures. Multiple drug resistance patterns of the bacteria to different antibiotics were determined using the Bauer Kirby disc diffusion technique. Metallo – β lactamase production was determined using E – test strip. Data were subjected to descriptive statistics using Statistical Package for Social Sciences (SPSS) software. A total of 145 isolates were identified as Pseudomonas aeruginosa from the clinical samples.Thirty were positive for metallo β lactamase production; 11 (8 %) males and 19 (13 %) females. Absolute resistance to ceftazidime (100 %), gentamicin (100 %), ceftriaxone (100 %) were observed while low resistance to ciprofloxacin (12.4 %), piperacillin (6.9 %) and imipenem (6.9 %). All isolates were sensitive to colistin. This study had demonstrated that there is a high occurrence of metallo β lactamase enzyme producing and antibiotic-resistant strains of P. aeruginosa in clinical specimens from the studied area. Necessary measures must be implemented to stop the problems of this antibiotic resistance.
Nanocomposites Transformed from Polystyrene Waste/Antimony, Barium and Nickel Oxides Nanoparticles with Improved Mechanical Properties
Authors: Sabo Y.T. , Boryo D.E. , Chindo I.Y. , Habib A.I.
Published: February 2022

In this experiment, the oxide nanoparticles were synthesized via chemical precipitation and the nanocomposites were produced using in situ polymerization method with varying nanoparticles contents ranged from 0 to 5 g. The mechanical properties of the nanocomposites were investigated and compared with the values obtained for untreated polystyrene. It was observed that the mechanical properties were higher for the nanocomposites and increase with increasing nanoparticle concentrations in the samples. It can be observed that the untreated polystyrene gave a tensile strength of 945.25 N/mm2.  At high nanoparticle content of 5 g, the nanocomposite containing NiO nanoparticles showed a tensile strength of 973.83 N/mm2 while nanocomposite containing BaO nanoparticles gave a tensile strength of 968.19 N/mm2 and nanocomposite containing Sb2O3 nanoparticle gave a tensile strength of 955.53 N/mm2. The results indicate that the tensile strength and percentage elongation of all the nanocomposites improved with the addition of metal oxides nanoparticles compared with the untreated polystyrene. Slight decrease in percentage reduction in area of the nanocomposites was recorded. Conclusively, with these results, the PS/NiO nano composite showed a better trend of behaviour due to better interfacial interaction between the nanofillers and the polymer matrix followed by PS/BaO and PS/Sb2O3 nanocomposites. It is recommended that during the production of polymer nanocomposite, PS/NiO, PS/BaO and PS/Sb2O3 nanocomposites could be used as reinforcements in the construction of buildings to add structural stability to the building.
Hepatoprotective and Antidyslipidemia Effect of Jatropha Tanjorensis Leaf Extract in Isoprenaline Induced Myocardial Infarction in Albino Rats
Authors: Ajah O. , Alaebo P.O. , Obike C.A. , Odo C.E. , Omodamiro O.D. , Egbuonu A.C.C.
Published: February 2022

Background: Recently, there is an increase in the incidence of myocardial infarction which manifest as a result of disrupted blood supply and oxygen to the myocardium.

Objective: This study assessed the protective outcome of methanol extract of Jatropha tanjorensis leaf on liver function biomarkers and lipid profile condition in the isoprenaline induced myocardial infarction in albino rats.

Methods: Thirty six (36) rats were divided at random into six (6) groups of six rats per group. Group 1 was normal control, group 2 was negative control (85mg/kg of isoprenaline only), group 3 positive control (pretreated with 2mg/kg carvedilol for 28 days), group 4 through 6 were pretreated with 200mg/kg, 400mg/kg and 600mg/kg of methanol leaves extract of Jatropha tanjorensis respectively for 28 days.

Results: The extract at 200mg/kg and 400mg/kg significantly (p<0.05) decrease the AST and ALT activities, TAG and Cholesterol concentrations compared to negative control. The extract treated groups also showed significant (p<0.05) increase in the HDL concentration. The histopathological study showed marked atrophy of hepatic cord in the 600mg/kg of the extract treated group. This pointed that the extract at 600mg/kg dose could not possess hepatoprotective potency. The 400mg/kg dose extract ameliorated damage cells.

Conclusion: This study revealed that 400mg/kg of the extract could serve as an agent for the prevention of hepatic cell injury and dyslipidemia.
Verapamil hydrochloride nanoparticles formulated with chitosan and sodium alginate by an ionic gelation method
Authors: Moeed Abdul , Khalid Arwa , Bashir Sajid , Bashir Hamid , Al Kahraman Yasser M.S.A. , Ismail Tariq , Amirzada Muhammad I.
Published: February 2022

Purpose: To formulate chitosan-based nanoparticles for extended release of verapamil so as to reduce its dosing frequency.

Methods: Nanoparticles of chitosan and sodium alginate loaded with verapamil HCl were synthesized using the ionotropic gelation method. The formulations were optimized by cross linking of tripolyphosphate with chitosan, and CaCl2 with sodium alginate at different concentrations. The ionic gelation method was used to produce seven different formulations. The best formulation for nanoparticles preparation involved using 0.06 % sodium alginate with 18 mM CaCl2 and of chitosan: TPP (5:1 ratio). The compatibility of verapamil HCl with sodium alginate and chitosan was tested using FTIR.

Results: Verapamil nanoparticles had a direct correlation with the polymer concentrations used. A 5:1 ratio of chitosan:TPP resulted in a particle size of 173 nm, and high drug entrapment. The size of verapamil nanoparticles prepared with sodium alginate was 186 nm (p = 0.02). Cross-linking agent played an important role in the preparation of the nanoparticles. Scanning electron micrographs showed that the nanoparticles were coalesced with one another, and had rough surfaces. Chitosan-based formulations had an entrapment efficiency in the range of 38.63 – 50.58 %, while the entrapment efficiency of sodium alginate-based formulations was 11.70 – 40.57 % (p 0.43).

Conclusion: Verapamil nanoparticles have been successfully formulated by ionic gelation method using natural polymers. The nano-formulations did not exhibit polymer-drug interactions, but manifest extended drug-release profiles.
Acute and sub-acute toxicity studies on an antidiabetic polyherbal formulation in mice
Authors: Abdillah Syamsudin , Nafisa Safira , Dewi Qonita S.
Published: February 2022

Purpose: To investigate the acute and sub-acute toxicity of an Indonesian polyherbal formulation in experimental mice.

Methods: Young and healthy Swiss albino mice of both sexes (5 – 6 weeks old), weighing 24 – 25 g were used in this study. Acute toxicity test was conducted in the mice using OECD 425 method and AOT425StatPgm software to determine the polyherbal formulation’s lethal dose (LD50) value, while the sub-acute toxicity test was performed for 28 days using OECD 407 method, by measuring hematological and clinical biochemistry parameters, as well as examining the histology of the liver and kidneys. The acute toxicity test consisted of the following dose groups: 175, 550, 1750 and 5000 mg/kg, while sub-acute toxicity test dose groups were 200, 400 and 800 mg/kg. Each group consisted of 5 male and 5 female mice.

Results: Based on the results obtained, LD50 value of the polyherbal formula was >5000 mg/kg. Repeated doses for 28 days showed significant differences (p < 0.05) for white blood cells (WBC) and platelet parameters in male mice, and for mean corpuscular volume (MCV), mean corpuscular hemoglobin concentration (MCHC), and platelet parameters in female mice. However, the values were within normal limits. With regard to clinical biochemical parameters - aspartate aminotransferase (AST), Alanine aminotransferase (ALT), blood urea nitrogen (BUN), creatinine, and albumin - there were no significant differences (p > 0.05) between the test groups. Furthermore, no changes were observed in their histological features.

Conclusion: The evaluated polyherbal formulation can be considered safe for use in mice. However, clinical trials in diabetic patients at the proposed doses are required to ascertain the formulation’s safety profile.
Effect of Kelulut honey supplementation on bone health in male rats on high-carbohydrate high-fat diet
Authors: Ekeuku Sophia Ogechi , Chin Kok-Yong , Ramli Nur Zuliani , Zarkasi Khairul Anwar , Ahmad Fairus
Published: February 2022

Purpose: To determine the effects of Kelulut honey (KH) on the bone health of rats with metabolic syndrome.

Methods: Male Wistar rats were randomised into normal control and metabolic syndrome is fed with a diet enriched with carbohydrate and fat. The rats in the metabolic syndrome arm were further assigned into the negative control group and honey group supplemented orally with Kelulut honey (1g/kg) daily for eight weeks. After the rats were sacrificed, the trabecular and cortical micro-architecture of the harvested femur was analysed using X-ray micro-computed tomography, while histomorphometric method was used to determine bone cell indices. Femoral biomechanical properties were analysed using a universal mechanical tester.

Results: Total cross-sectional area, osteoid surface and volume, displacement and strain reduced significantly, while eroded surface increased significantly in the rats with metabolic syndrome than the normal rats (p < 0.05). The honey group showed a significant reduction in osteoclast surface than the normal healthy control (p < 0.05). Other skeletal parameters did not show a significant intergroup difference.

Conclusion: Metabolic syndrome is harmful to bone health and honey has limited effects in reversing these negative effects.
Effect of sodium butyrate on glucose and lipid metabolism, insulin expression and apoptosis of β-cells in obese pregnant rats
Authors: Zhang Haiyan , An Lihong , Yang Youlin , Chen Yi , Zhang Xiahui , Dai Zhenzhen
Published: February 2022

Purpose: To study the influence of sodium butyrate on the metabolism of lipid and glucose, insulin expression and apoptosis of β-cells in obese pregnant rats.

Methods: Three groups of one hundred and twenty 4-week-old female C5BL/6J mice were used: control, high-fat diet and sodium butyrate groups. Insulin, triglycerides and total cholesterol were evaluated by enzyme-linked immunosorbent assay (ELISA). Insulin levels, as well as area and quality of islet β-cells were assessed using Image Pro Plus software. The number of DAPI-positive islet cells, positive expression of bcl-2 in each islet cell, and apoptosis of islet β-cells in each group were determined.

Results: The expression levels of insulin in high-fat diet group and butyrate group were significantly reduced, relative to control, but insulin expression level in Na butyrate group increased, relative to high- fat diet mice (p < 0.01). The area and quality of islet β-cells in high-fat diet and sodium butyrate groups were markedly higher in sodium butyrate group than in high-fat diet group (p < 0.01). The bcl-2 expression in islet β-cells rose in mice given high-fat diet, relative to control and sodium butyrate groups (p < 0.01).

Conclusion: Sodium butyrate facilitates glucose and lipid metabolism, but increases insulin expression, and effectively inhibits apoptosis of islet β-cells in obese pregnant mice. Thus, sodium butyrate may be useful in the prevention and treatment of metabolic disorders due to diabetes mellitus (DM).
Geologia e características do fluido mineralizador dos alvos auríferos Jerimum de Cima e Babi, campo mineralizado do Cuiú-Cuiú, Província Aurífera do Tapajós, Cráton Amazônico, com base em estudos de inclusões fluidas e de isótopos estáveis
Authors: Silva Júnior Carlos Alberto Dos Santos , Klein Evandro Luiz
Published: February 2022

Os alvos auríferos Jerimum de Cima e Babi estão localizados no campo mineralizado do Cuiú-Cuiú, Província Aurífera do Tapajós, Cráton Amazônico. Jerimum de Cima é moderadamente mineralizado, enquanto no alvo Babi a mineralização é incipiente (não econômica). O estudo petrográfico definiu tonalitos, monzogranitos e granodioritos como rochas hospedeiras nos dois alvos. Sericitização, silicificação, sulfetação, cloritização e carbonatação ocorrem nos dois alvos, na forma fissural e disseminada (pervasiva), e os maiores teores de ouro estão associados com maiores concentrações de sulfetos. Inclusões fluidas (IF) aquosas, aquocarbônicas e carbônicas foram classificadas. As IF aquocarbônicas, presentes apenas em Jerimum de Cima, representam o provável fluido mineralizador, indicam imiscibilidade de fluidos (separação de fases) e possível mistura tardia com fluidos mais frios. Estudos de isótopos estáveis em minerais de veios e de zonas de alteração indicam temperaturas de precipitação dos minerais entre 305 e 330 °C e entre 108 e 205 °C. Também sugerem fontes magmáticas e meteóricas para os fluidos. Os dados obtidos são compatíveis com depósito magmático-hidrotermal (relacionado à intrusão), com mistura de fluido magmático e meteórico. A ausência de CO2 no alvo Babi, assumindo que o aprisionamento do fluido tenha sido tardio em relação à evolução hidrotermal do sistema, pode explicar a fraca mineralização.
Moluscos da Formação Romualdo, Aptiano-Albiano, Bacia do Araripe, nordeste do Brasil
Authors: Pereira Priscilla Albuquerque , Cassab Rita de Cássia Tardin , Barreto Alcina Magnólia Franca , Almeida José Augusto Costa de
Published: February 2022

A Formação Romualdo contém assembleias fósseis de invertebrados compostas principalmente de moluscos gastrópodos e biválvios, equinoides, táxons importantes e indicativos de influência marinha durante o Aptiano-Albiano da Bacia do Araripe, no nordeste do Brasil. Este trabalho descreve e ilustra formalmente moluscos gastrópodos e biválvios da Formação Romualdo, pontuando as características paleoecológicas dos gêneros com base em 750 espécimes dos estados de Pernambuco, Ceará e Piauí. Esta análise resultou na identificação dos gastrópodos Cerithium sergipensis Maury, 1936 e Tylostoma ranchariensis n. sp. e os biválvios Aguileria dissita White, 1887, Corbula sp. e Brachidontes araripensis n. sp.. Caracteres paleoautoecológicos indicam gastrópodos epifaunais, biválvios epifaunais e semi-infaunal bissado, indicativos de ambiente marinho raso (interdital-subtidal) a lagunas interditais. A presença das espécies Cerithium sergipensis e Aguileria dissita nas formações Romualdo (Aptiano-Albiano, Bacia do Araripe) e Riachuelo (Albiano, Bacia de Sergipe) caracteriza um bioevento regional de irradiação adaptativa. A ocorrência de uma nova espécie de Tylostoma sugere influência marinha oriunda do Mar de Tétis, uma vez que esse gênero é característico do Domínio Tetiano, representando um bioevento local de inovação biológica pelo sucesso de seu desenvolvimento nas formações citadas e por processos geológicos favoráveis em nível global.
Parque Estadual das Fontes do Ipiranga: unidade de conservação importante para a proteção da brioflora da Mata Atlântica na cidade de São Paulo, Brasil
Authors: Visnadi Sandra Regina
Published: February 2022

O Parque Estadual das Fontes do Ipiranga (PEFI) é a terceira maior reserva de mata nativa do município de São Paulo. O trabalho evidencia a diversidade das briófitas no PEFI, listando 266 espécies para esse parque, cujo material totaliza 1.818 exsicatas do Herbário do Instituto de Botânica de São Paulo (SP). A brioflora do PEFI é típica da Mata Atlântica de encosta do estado de São Paulo. A alta similaridade das áreas antrópicas e florestais do PEFI evidencia que a arborização das áreas antrópicas e a manutenção das áreas florestais nos seus arredores minimizam os efeitos do desmatamento na brioflora. A Mata Atlântica que cobre o PEFI ressalta a importância do parque na proteção da flora de briófitas desse ecossistema. O PEFI ainda se destaca pelo registro inédito de espécies para São Paulo [Brachythecium plumosum (Hedw.) Schimp., Lepidopilidium plebejum (Müll. Hal.) Sehnem, Riccia enyae Jovet-Ast], pela ocorrência de espécies que no Brasil se restringem ao estado paulista [Bryum challaense Broth., Cololejeunea microscopica (Taylor) Schiffn., Drepanolejeunea subdissitifolia Herzog, Eurhynchium hians (Hedw.) Sande Lac., Lejeunea lamacerina (Steph.) Schiffn., Lepidolejeunea bidentula (J.B. Jack & Steph.) R.M. Schust.] e pela ocorrência de 16 espécies endêmicas do Brasil.
Ordenamento participativo do turismo com botos no Parque Nacional de Anavilhanas, Amazonas, Brasil
Authors: Vidal Marcelo Derzi , Santos Priscila Maria Da Costa , Jesus Josângela Da Silva , Alves Luiz Cláudio Pinto de Sá , Chaves Maria do Perpétuo Socorro Rodrigues
Published: February 2022

Neste artigo, apresentamos as estratégias desenvolvidas para o ordenamento do turismo com botos (Inia geoffrensis) no Parque Nacional de Anavilhanas, Amazonas, Brasil. Utilizando-se de ferramentas de diagnóstico, de planejamento e de gestão participativa junto aos atores relacionados ao turismo local, foram elaboradas e colocadas em prática normas e orientações quanto à estrutura mínima e à localização do empreendimento onde as interações com os botos acontecem, bem como ao modo como as interações dos visitantes com os animais devem ser desenvolvidas. Estas diretrizes reduzem significativamente os riscos de acidentes e aumentam os benefícios que o turismo com os botos no Parque Nacional de Anavilhanas oferece, podendo subsidiar a elaboração de futuros projetos e de políticas públicas voltadas para a gestão do uso público em outras áreas protegidas.
Distribuição e conservação das espécies de Aiouea Aubl. (Lauraceae Jussieu) no Brasil
Authors: Franciscon Carlos Henrique , Miranda Izildinha De Souza
Published: February 2022

Este estudo objetiva apresentar uma revisão biogeográfica da distribuição (real e potencial) e do estado de conservação das espécies de Aiouea Aubl. (Lauraceae Jussieu) no Brasil. As informações são oriundas da rede SpeciesLink, que integra dados primários de coleções científicas e está interligada ao sistema Biogeografia da Flora e Fungos do Brasil (Biogeo), a partir das quais foram definidos a distribuição real e os modelos de distribuição potencial para cada espécie brasileira de Aiouea, baseando-se em um modelo de consenso, gerado por até cinco algoritmos. Também foram analisados a situação de endemismo no Brasil, o estado de conservação e a raridade das espécies. Foram encontrados 1.433 registros para 14 espécies de Aiouea no Brasil. Na seleção dos registros para o estudo, o percentual de perda total foi alto (64,2%), devido principalmente à falta de georreferenciamento e de determinador (60,8%). Na avaliação dos modelos de consenso, foram considerados bons resultados apenas para as espécies com 20 ou mais pixels. As demais apresentaram muitos erros e, por isso, seus modelos servem somente para orientar novas áreas para coletas. A distribuição geográfica mostra um padrão predominante para a Amazônia brasileira; nove espécies são endêmicas do Brasil e 11 apresentaram algum indicador de raridade.
Predação de Columbina squammata Lesson, 1831 (Aves: Columbidae) por Cariama cristata Linnaeus, 1766 (Aves: Cariamidae)
Authors: Moreira Sandro Gonçalves
Published: February 2022

O presente trabalho relata o primeiro registro de predação de fogo-apagou (Columbina squammata Lesson, 1831) por seriema (Cariama cristata Linnaeus, 1766), na zona rural do município de Uberlândia, Minas Gerais, Brasil.
Are Mauritia flexuosa L. f. palm swamps in the Brazilian Pantanal true veredas? A floristic appraisal
Authors: Moreira Suzana Neves , Pott Vali Joana , De Souza Evaldo Benedito , Pott Arnildo
Published: February 2022

In this first report on the flora of Mauritia flexuosa L. f. palm swamps in the Pantanal wetland of Brazil, we surveyed and compared the angiosperm flora of eight areas of palm swamps in the Pantanal plain to determine if they correspond to veredas. Studied areas were four sites near the upland in Rio Verde and Coxim, and four in the Parque Estadual do Pantanal do Rio Negro, Aquidauana, state of Mato Grosso do Sul, Brazil. To determine species similarity, we compared our results with inventories of aquatic plants of the Pantanal and of species of veredas in the state. Using the wandering method, we recorded a total of 385 species of phanerogams. Species richness was higher in Rio Verde/Coxim (273 species) than in Rio Negro (243 species), with a similarity of 33.7%. We found a rare and endemic plant, Polygala grazielae Marques, first record in the Pantanal. We found that both sites correspond to two types of palm swamps but with different floras. The species associated with M. flexuosa in the park are much the same as those of seasonally flooding grasslands of the Pantanal, while on the edge of the plain many species are common to the upland true veredas, particularly on organic soil. Thus, we conclude that the Rio Verde/Coxim areas are true veredas. These palm swamps and veredas in the Pantanal should receive the same legal protection as the veredas in Cerrado.
Reproductive phenology of Polygonum hispidum Kunth and P. punctatum Elliott (Polygonaceae), in response to the flooding cycle in the Pantanal, Brazil
Authors: Catian Gisele , Scremin-Dias Edna , Pott Arnildo
Published: February 2022

In flood-driven environments the life cycles of organisms are regulated in function of the water regime. The objective of this work is to analyse the phenophases of flowering and fructification of two species of amphibious aquatic macrophytes, Polygonum hispidum Kunth and P. punctatum Elliott, with regard to the flooding cycle of the Brazilian Pantanal. We collected monthly data in 26 plots of 20 ponds during two years. The flooding phases were classified as drought, rising, flood, and receding. The periods with an abundance of water (rising, flooding, and receding) were the most important for reproduction. Both species bear fruits at flood, when the water is deepest and remains until receding, and most seeds are dispersed. The synchrony between reproductive cycles and these flood phases suggests the importance of seasonality in the reproductive patterns of these species.