bluuebunny/crossref_metadata_2025 huggingface dataset:
Overview on modeling and management of Smart Grids
Authors: Khaldi Jihen El , Bouslimi Lotfi , Wertani Hamza , Lakhoua Mohamed Najeh
Published: August 2021

The concept of Smart Grids refers to a complex ecosystem that can be described as a combination of systems to capture its most structural elements. When studying these complex systems, the traditional tools of the Cartesian methods have shown their limits. There is therefore a need to resort to other methods to model them. These modeling methods are generally classified and grouped into five families: functional modeling, decision modeling, resource modeling, information modeling and mixed modeling.  This review provides an overview of the state of the art of an intelligent network. The classification of modeling methods is also presented. Then an application of the bond graph approach will be explained. Finally we describe a general idea on the management of smart grids.
Investigating how consumer education and lifestyle influence the consumer empowerment: case in rural and urban areas, Indonesia
Authors: Simanjuntak Megawati
Published: August 2021

This study aimed to analyze the difference of consumer education, lifestyle, and consumer empowerment in rural and urban areas, and to analyze the effect of consumer education and lifestyle on the consumer empowerment. This research used a cross-sectional design study with 120 housewives as the sample selected purposively. Data were analyzed using independent sample t-test, Mann-Whitney, and multiple linear regressions. There were significant differences (p<0.01) in consumer education, fulfilled lifestyle, believer lifestyle, and consumer empowerment index between the two regions, where the urban area scores were higher compared to the rural area. Consumer education and length of education affected positively and significantly (p<0.01) on the consumer empowerment index, while the lifestyle did not significantly affect the consumer empowerment index. The higher intensity of consumer education and higher education levels will increase the consumer empowerment index.
Classification of research and applications of the computer aided process planning in manufacturing systems
Authors: Soori Mohsen , Asmael Mohammed
Published: August 2021

The Computer Aided Process Planning (CAPP) systems are recently developed in manufacturing engineering to provide links between Computer Aided Design (CAD) and Computer Aided Manufacturing (CAM) systems. The CAPP systems are developed by considering the different issues of computer applications in production engineering. Optimization techniques can be applied to the CAPP to increase efficiency in part production processes. The energy consumption of part production process can be analyzed and optimized using the CAPP systems in order to increase added value in the part manufacturing process. Also, artificial neural networks as well as cloud manufacturing systems can be applied to the CAPP systems to share advantages of the different CAPP systems in different industry applications. Flexible process planning systems are developed using dynamic CAPP in order to cope with product varieties in process of part production. To develop potential energy saving strategies during product design and process planning stages, the advanced CAPP systems can be used. In this paper, a review of Computer Process Planning systems (CAPP) is presented and future research works are also suggested. It has been observed that the research filed can be moved forward by reviewing and analyzing recent achievements in the published papers.
Assessing the effects of flipped classroom at the Tunisian university
Authors: Ben Kahla Karim , Khanchel Hanen
Published: August 2021

At the beginning of 2020, e-learning was not yet valued in the culture of Tunisian university. However, the COVID-19 Pandemic was the cause of the accelerated deployment of e-learning-related devices. Moreover, it seems that the context of health crisis experienced in the world and particularly in Tunisia represents a factor pushing Tunisian university to reduce, or even eliminate, face-to-face courses for precautionary measures. This is likely to allow students to improve their knowledge, especially for those who require great concentration and time for reflection. The paper shows a very different approach with an analysis of the students’ difficulties by focusing on the mistakes made in solving the problems in the case study. The study makes an original contribution to knowledge. It breaks new intellectual ground. Indeed, flipped learning in particular seems to affect students on a psychological level, making them more engaged, more motivated, and better able to self-regulate. This is the intuition of many flipped learning instructors, but intuition is just a hypothesis. Nevertheless, the results indicate that there is a gap as regards the flipped classroom approach.
Financial literacy among high school teenagers in a developing country context - an empirical study with reference to high school students in Addis Ababa, Ethiopia
Authors: ELifneh Yohannes Workeaferahu
Published: August 2021

Both developed and developing countries and economies have become increasingly concerned about the level of financial literacy of their citizens. Previous studies indicate that unlike the case in the industrialized world, the issue of financial literacy is a contemporary issue in the developing world, and it is an understudied field in this context. This study was initiated to survey the level of basic financial literacy among high school students in Addis Ababa, Ethiopia’s capital. Such a study corresponds to global initiatives such as by OECD requesting scholars to show case the level of financial literacy among young people in different countries/contexts. The data collection instrument was a standard questionnaire that measures the level of basic financial literacy of high school teenagers in Ethiopia. The questionnaire is based on the instrument originally developed by Lusardi and  Mitchell, (2005); and this study uses the slightly updated version used by Van Rooij, Lusardi and Alessie, (2011) that measures basic financial literacy from angles of numeracy, interest compounding, inflation, time value of money, and money illusion. The study concludes that the level of financial literacy is not fairly good among the high school students. The high school students in the capital are not well versed with the basic financial literacy dimensions/measurements, mainly with the assessments of interest compounding, inflation, time value of money, and money illusion. The worst assessment results are a 90.8% failure in the money illusion question, a 70.9% failure in interest compounding assessment question, and a 62.7% failure in the time value of money assessment question. These are followed by a 58.4% failure in the inflation assessment question and a 31.3% failure in the easiest assessment question of numeracy. By and large, these findings testify that the high school students in Addis Ababa have serious deficiency in basic financial literacy. Policy makers and educators may need to seriously pay attention to this shocking deficiency in the level of basic financial literacy among the high school students and take measures to educate the youth this basic life skill at young age while they are still at school.JEL Classification Code: D14
Workplace incivility and turnover intention among nurses of public healthcare system in Pakistan
Authors: Samad Abdul , Memon Salman Bashir , Maitlo Ayaz Ali
Published: August 2021

Though workplace incivility is a negative behavioral phenomenon that has infiltrated almost every sector, yet, less investigated in the healthcare sector. The healthcare sector is the backbone for economic and well-being for any nation and mainly composed of nurses. Turnover among nurses is a serious challenge to public healthcare facilities in terms of management, financing, and service quality. Based on the COR theory, this study capitalizes investigation on the effects of incivility on turnover intention through burnout and occupational stress. Simple random sampling was deployed on a sample of 265 nurses from 24 public hospitals of Sindh in Pakistan. Data analysis through partial least square and results revealed that workplace incivility has insignificant relation with turnover intention. Whereas, incivility has a significant indirect relationship with turnover intention through burnout and occupational stress. This study suggests that emotional and occupational depletion in public healthcare is high due to incivility at the workplace. Thus, HR managers must devise policies to practice civil behavior to curtail turnover intention problem among nurses. Besides practical benefits, some limitations with potential future research directions are discussed in the end.
Study of segmentation for the users of personal care products
Authors: Lahoti Archana Y. , Jain Dhiraj
Published: August 2021

Person care products (PCP) occupies a major chunk of the market thus making it a largest consumer sector in India. Today due to the media influence, the consumers consider personal care products as a symbol of their life quality and self-image. The objective of this research is to study demographic profile of consumers in the field of personal care products and further segment them on the basis of their buying motive and product preference. A survey of 706 respondents was conducted with structured questionnaire. The questionnaire had demographic questions along with some specific questions to study and segment the consumer group of personal care products. The data was analysed using descriptive statistics and Clustering Analysis using SPSS V20. Clustering Method is used to study group of respondents based on different set of variables. The results of Clustering analysis reveal that marketing mix motives such as product, price, buying convenience, promotional offers and the buying and consumer value motives like quality, brand name, packaging, credibility, natural ingredients and past product experience, plays a vital role while purchasing Personal Care Products.
Relationship between social media marketing practices and customer response with mediating role of brand equity dimensions: an empirical investigation
Authors: Shadi Elmira , Hesari Ailar Ebrahimi , Shahrabi Behzad
Published: August 2021

This study aims to investigate the relationship between social media marketing practices and customer response with consideration of the mediating role of brand equity dimensions through structural equation modeling in an empirical case study. Data are analyzed using structural equation modeling. The following findings are found: The results show that there is a significant relationship between social media marketing practices and customer response in the survey sample. Additionally, the hypothesis about the mediating role of brand equity dimensions is also supported. The results of our research augment our understanding of the role of social media marketing practices in stimulating customer response (electronic word-of-mouth and commitment) and the role of brand equity dimensions (brand awareness and brand image).
Impact of environmental cost on the profitability of quoted manufacturing companies in Nigeria
Authors: Worimegbe Temitope Mariam
Published: August 2021

Corporate involvement in environmental initiatives and reporting is essential for increasing and sustaining performance in a dynamic and changing environment. However, this involvement in environmental activities is not without costs implication. Hence, business managers tend to sacrifice engaging and reporting environmental initiatives for economic benefits. This study examined the impact of environmental costs on the profitability of quoted manufacturing companies from 2007 to 2017. The study used the ex-post facto research design. Twenty mentioned manufacturing companies were purposively drawn from the population of sixty manufacturing companies listed on the floor of the Nigerian Stock Exchange. The study variables were sourced from the annual reports and accounts as well as the stand-alone environmental information of the selected companies over eleven years from 2007-2017. The cost incurred on environmental initiatives to the community and training of employees on environmental concerns were used as proxies for environmental cost. At the same time, the DuPont return on equity was proxy for profitability. The findings from the panel random-effect regression analysis showed that asset use efficiency (F = 3.368, p = .01) and equity multiplier (F = 3.3301, p = .01) were significantly influenced by environmental cost; while operating efficiency (F= 0.5158, p = .72) was not significantly impacted by environmental cost at 5% level of significance. As such, in this study, the asset use efficiency and equity multiplier are the main drivers of a significant increase in the return on equity of quoted manufacturing companies in Nigeria from 2007 to 2017. The study, therefore, concluded that environmental costs significantly affect the profitability of quoted manufacturing companies in Nigeria.
The effect of demographic, social, and economic characteristics on consumer empowerment in education institutions
Authors: Simanjuntak Megawati , Umiyati Siti
Published: August 2021

Nowadays, consumers are faced with many options for formal educational institutions. To choose the best institution, consumers need to be well educated and well informed. This research aimed to analyze the influence of demographic, social, and economic characteristics toward formal educational institution consumer empowerment. This research used a cross-sectional study of 52 respondents. The data were analyzed using descriptive and inferential analysis. The consumer’s empowerment index in this research was 54.34, which was included in the capable category. The result showed that early adult (19-24 years) females who were highly educated and were not having a job with ≤ Rp3,204,551 income per month were the most empowered group of respondents than others. Regression analysis revealed that age influenced the consumer empowerment index. T-test analysis of the consumer empowerment based on characteristics is not significantly different.
Institutionalization in service providing companies: analysis in recruitment and selection consultancies (R&S)
Authors: Chaves Carla Milena Lordêlo , Luft Maria Conceição Melo Silva , Rocha Ronalty
Published: August 2021

Research supported by institutional theory contributes to organizational studies because they insert variables such as shared values, search for legitimacy, and isomorphism in the analysis of relationships between organizations and between organizations and the environment. In this context, this article aims to analyze the stages of institutionalization in consulting companies providing services in the recruitment and selection of people (R&S). A qualitative-descriptive study was performed with six recruitment and selection consultancies located in Sergipe. The results demonstrated the administrative functioning of organizations about the stages of institutionalization, revealing an institutional scenario for these service providers, besides highlighting the main obstacles to the sedimentation of the companies analyzed.
An evaluation of Nigeria-Chad trade and security relations, 1988-2009
Authors: Ani Kelechi Johnmary
Published: August 2021

The contemporary world is such that nations cannot do without one another. This is because some nations are connected by historical, cultural, social, economic, scientific and other forms of strategic interests. Nigeria and Chad over the years have a history of inter-state relations that pre-dates the coming of colonial masters. However, at the end of colonial rule, both states engaged in multi-dimensional forms of bilateral relations. This study, which adopts mixed method of research focuses on Nigeria-Chad economic relations. It reveals the forms of trade agreement between both states. The study highlights formal and informal nature of the trade amongst the two states and found that their history of diplomatic relations has promoted the national interest as well as the management of strategic over-lapping trade demands in both countries. This study used regression analysis and applied unit root, co-integration, chow test, stability test as well as Phillips-Perron (PP) and Augmented Dickey-Fuller (ADF) to find-out that there is strong positive significant relationship between Nigeria-Chad trade and economic diplomacy within the period of 1970-2018 as well as reasonable stability in Nigerian trade and security relations with Chad in the presence of Boko Haram menace. The study recommends increased bilateral trade, border security as well as intelligence sharing on the dynamics of security threats to the relations of both states.
HW2,2
loc-regularity for p-harmonic functions in Heisenberg groups
Authors: Liu Jiayin , Peng Fa , Zhou Yuan
Published: August 2021

Let

1
<
p
≤
4

{1<p\leq 4}

when

n
=
1

{n=1}

, and

1
<
p
<

3
+

1

n
-
1

{1<p<3+\frac{1}{n-1}}

when

n
≥
2

{n\geq 2}

.
We obtain the second-order horizontal Sobolev

HW
loc

2
,
2

{\operatorname{HW}^{2,2}_{\mathrm{loc}}}

-regularity of p-harmonic functions in the Heisenberg group

ℍ
n

{{\mathbb{H}}^{n}}

.
This improves the known range of p obtained by Domokos and Manfredi in 2005.
Approximate nonradial solutions for the Lane-Emden problem in the ball
Authors: Fazekas Borbála , Pacella Filomena , Plum Michael
Published: August 2021

In this paper we provide a numerical approximation of bifurcation branches from nodal radial solutions of the Lane Emden Dirichlet problem in the unit ball in ℝ2, as the exponent of the nonlinearity varies. We consider solutions with two or three nodal regions. In the first case our numerical results complement the analytical ones recently obtained in [11]. In the case of solutions with three nodal regions, for which no analytical results are available, our analysis gives numerical evidence of the existence of bifurcation branches. We also compute additional approximations indicating presence of an unexpected branch of solutions with six nodal regions. In all cases the numerical results allow to formulate interesting conjectures.
Experimental determination and modeling of flow curves of xanthan gum solutions over a large range of shear rates
Authors: Sepulveda Julian , Montillet Agnes , Valle Dominique Della , Amiar Thanina , Ranchon Hubert , Loisel Catherine , Riaublanc Alain
Published: August 2021

The viscosities of solutions formulated with xanthan gum and xanthan gum with whey protein isolates are experimentally characterized and modeled over a wide range of shear rates [10−3to 105s−1]. As shown by numerous studies [1, 2], the generation of vortices in the cone-plate geometry is making viscosity measurements beyond a certain shear rate unreliable. In the present work, an innovative technique, based on microfluidics and developed by the company Formulaction, has been employed to extend to high shear rates, the viscosity flow curve obtained with a rotational rheometer. The main highlights of this study are firstly, to propose a scaling law for the inertial transition in the cone-plate geometry for different diameters and angles through the determination of the maximum shear rate at which one can expect a true viscosity value. Secondly, the high shear rate measurements allow the determination of the second Newtonian plateau for these solutions thanks to the Williams-Carreau model. An attempt for the second plateau modeling is proposed following the concept of an intrinsic viscosity in the high shear equilibrium. In the same way, other fitted parameters from the Williams-Carreau law are modeled as a function of the polymer concentration. This procedure allows to provide a predictive model for the rheological behavior of xanthan gum-based solutions used in high shear processes like high pressure homogenization, emulsification, foaming, microfluidics, etc in food, pharmaceutical or cosmetics applications.
Macroalgal canopies reduce beta diversity in intertidal communities
Authors: Scrosati Ricardo A. , Catalán Alexis M. , Valdivia Nelson
Published: August 2021

Species diversity in a habitat is often termed alpha diversity. As it influences various community properties, many studies have investigated its drivers. For instance, intertidal macroalgal canopies limit understory thermal stress during low tides and thus often increase alpha diversity. More recently, beta diversity has also become of interest. Beta diversity measures the change in species composition across space and is another important attribute of communities because it influences their multifunctionality, productivity, and resilience. Using data from a field experiment done in Atlantic Canada, we tested the hypothesis that fucoid macroalgal canopies limit beta diversity in intertidal communities. This prediction stems from previous evidence that such canopies limit thermal variation across the substrate during low tides, an important consideration because spatial thermal changes influence spatial variability in species composition. To test our hypothesis, we compared two treatments (full canopy cover and canopy removal) created the year before on intertidal areas that were originally all fully covered by canopies. Separately for each treatment, we calculated beta diversity as the Bray-Curtis dissimilarity between nearby quadrats using species abundance data. Overall, fucoid macroalgal canopies significantly reduced beta diversity, showing that these foundation species can have opposing effects on alpha and beta diversity.
The multicenter European Biological Variation Study (EuBIVAS): a new glance provided by the Principal Component Analysis (PCA), a machine learning unsupervised algorithms, based on the basic metabolic panel linked measurands
Authors: Carobene Anna , Campagner Andrea , Uccheddu Christian , Banfi Giuseppe , Vidali Matteo , Cabitza Federico
Published: August 2021

Objectives

The European Biological Variation Study (EuBIVAS), which includes 91 healthy volunteers from five European countries, estimated high-quality biological variation (BV) data for several measurands. Previous EuBIVAS papers reported no significant differences among laboratories/population; however, they were focused on specific set of measurands, without a comprehensive general look. The aim of this paper is to evaluate the homogeneity of EuBIVAS data considering multivariate information applying the Principal Component Analysis (PCA), a machine learning unsupervised algorithm.

Methods

The EuBIVAS data for 13 basic metabolic panel linked measurands (glucose, albumin, total protein, electrolytes, urea, total bilirubin, creatinine, phosphatase alkaline, aminotransferases), age, sex, menopause, body mass index (BMI), country, alcohol, smoking habits, and physical activity, have been used to generate three databases developed using the traditional univariate and the multivariate Elliptic Envelope approaches to detect outliers, and different missing-value imputations. Two matrix of data for each database, reporting both mean values, and “within-person BV” (CVP) values for any measurand/subject, were analyzed using PCA.

Results

A clear clustering between males and females mean values has been identified, where the menopausal females are closer to the males. Data interpretations for the three databases are similar. No significant differences for both mean and CVPs values, for countries, alcohol, smoking habits, BMI and physical activity, have been found.

Conclusions

The absence of meaningful differences among countries confirms the EuBIVAS sample homogeneity and that the obtained data are widely applicable to deliver APS. Our data suggest that the use of PCA and the multivariate approach may be used to detect outliers, although further studies are required.
Environmental and thermodynamic performance assessment of biomass gasification process for hydrogen production in a downdraft gasifier
Authors: Marzoughi Tayebeh , Samimi Fereshteh , Rahimpour Mohammad Reza
Published: August 2021

Gasification is one of the most efficient techniques for sustainable hydrogen production from biomass. In this study, a comparative performance analysis of the gasification process using various types of biomass materials was undertaken via thermodynamic approach. Air, steam, and air/steam as the traditional gasifying agents were applied to provide an opportunity to choose the most proper agent in the process. This paper also evaluates the environmental impacts of the process in terms of CO2emission by using Aspen Energy Analyzer. The effects of agent to biomass molar ratio, agent inlet temperature, moisture content of biomass material, and gasification temperature were estimated based on the producer gas compositions, hydrogen yield and heating values. The results indicate that the highest hydrogen yield (0.074 g H2/g biomass) was obtained in the steam gasification of plastic, while air gasification of paper generates the lowest one. It was also observed that manure is the most beneficial from environmental perspectives, while tire and plastic have the highest contribution to CO2emission and consequently global warming. The higher values of hydrogen production and LHV of produced gas are associated respectively with using steam, air/steam, and air as the gasification agents. The lowest value of CO2emission is obtained for air, air/steam, and steam as the gasifying agents, respectively.
Illustrating catalysis with a handmade molecular model set: catalytic oxidation of carbon monoxide over a platinum surface
Authors: Horikoshi Ryo , Nakajima Syota , Hosokawa Saburo , Kobayashi Yoji , Kageyama Hiroshi
Published: August 2021

Catalytic converters (automotive catalysts) and the chemical reactions they catalyze appear in general and introductory chemistry textbooks. Although the detailed mechanisms of the chemical reactions that occur in catalytic converters have been clearly revealed via recent developments in surface and computational chemistry research, the description and illustration of the catalysis are still ambiguous in textbooks. In this paper, we describe an extracurricular lecture whereby a handmade teaching aid was employed to illustrate the basic principle of the catalytic oxidation of carbon monoxide over platinum surface, which is an essential reaction occurring in catalytic converters. The teaching aid, constructed combining easily available materials, can illustrate the positions and motions of the molecules on the platinum surface during catalytic oxidation. The lecture was favorably received by non-chemistry majors and high school students. Despite the difficulty of the topic, the audience displayed a relatively high level of understanding.
Generalized Bernoulli process: simulation, estimation, and application
Authors: Lee Jeonghwa
Published: August 2021

A generalized Bernoulli process (GBP) is a stationary process consisting of binary variables that can capture long-memory property. In this paper, we propose a simulation method for a sample path of GBP and an estimation method for the parameters in GBP. Method of moments estimation and maximum likelihood estimation are compared through empirical results from simulation. Application of GBP in earthquake data during the years of 1800-2020 in the region of conterminous U.S. is provided.
Topology optimized thermoelectric generator: a parametric study
Authors: Mativo John , Hallinan Kevin , George Uduak , Reich Greg , Steininger Robin
Published: August 2021

Typical thermoelectric generator legs are brittle which limits their application in vibratory and shear environments. Research is conducted to develop compliant thermoelectric generators (TEGs) capable of converting thermal loads to power, while also supporting shear and vibratory loads. Mathematical structural, thermal, and power conversion models are developed. Topology optimization is employed to tailor the TEG design yield maximal power production while sustaining the applied shear and vibratory loads. As a specific example, results are presented for optimized TEG legs with a void volume fraction of 0.2 that achieve compliance shear displacement of 0.0636 (from a range of 0.0504 to 0.6079). In order to achieve the necessary compliance to support the load, the power reduction is reduced by 20% relative to similarly sized void free TEG legs.
Design and simulation of piezoelectric nano cylindrical hollow structure for energy harnessing applications
Authors: Tyagi Naveen , Mahajan Aparna N. , Gaur Anshu Mli
Published: August 2021

This article investigates piezoelectric materials for harnessing vibrational energy. A nano hollow cylindrical structure based on various piezoelectric materials was designed and utilised to generate the voltage. An accurate and efficient model is developed here, so as to optimized the efficiency of the piezoelectric energy harvester. This work analyses the piezoelectric actuator deflection and involves the Eigen frequency computation. A measurement methodology for investigating the mechanical and electrical behaviour of vibrational harvester's was modelled and analysed by finite element method using COMSOL software. The energy harvesting structure was developed and tested with different piezoelectric materials to attain appreciable voltage through a small deflection. The Simulated results predicts that for the same pressure range, different piezoelectric materials have the different output voltage and Eigen frequencies. The maximum voltage was observed for Barium Titanate (3.0847 V at 250 µm), along with poled Polyvinylidene fluoride. In addition, a comparison was made with different piezoelectric materials ideally suited to intelligent cantilever structure. For optimizing the performance of the piezoelectric energy harvester an accurate and efficient model is required, which was developed in this simulation study. A high voltage value with a small deflection through a cylindrical hollow structure was designed and tested using various piezoelectric materials in this study.
A survey on the characterization parameters and lifetime improvement techniques of wireless sensor network
Authors: Singh Manish Kumar , Amin Syed Intekhab , Choudhary Amit
Published: August 2021

Emerging technologies, such as the Internet of things (IoT), machine learning (ML) and machine-to-machine networks encourage deployment of large-scale wireless sensor networks (WSNs). The major problem in WSN is the limited energy of node batteries. Therefore, the efficient use of node energy for data sensing, processing and communication operations is important to maintain a fully operational network for longest period of time. Literature presents a wide range of lifetime maximization techniques for WSN such as resource allocation algorithm, clustering and routing, sleep–wake scheduling, energy harvesting, MIMO technique, Distributed source coding, genetic algorithm and sink mobility. These techniques effectively lessen the energy consumption and enhance the lifetime of the entire wireless sensor network in various applications. Besides energy consumption, the characterization parameters such as coverage and connectivity, communication and modulation schemes, operational environment, network parameters, node parameters and service parameters also have great impact on WSN performance. This paper presents a comprehensive survey of state-of-the-art research works that improves the performance of WSN by optimizing various network characterization parameters and lifetime maximization techniques. These results highlight the key issues which affects WSN performance and provide a roadmap for WSN designers for effective implementation of novel WSN strategies.
Compact super-wideband MIMO antenna with improved isolation for wireless communications
Authors: Singh Ajit Kumar , Mahto Santosh Kumar , Sinha Rashmi
Published: August 2021

This paper presents a miniaturized dual-element Super-Wideband (SWB) Multiple-Input-Multiple-Output (MIMO) antenna. The operation bandwidth is enhanced by 175% with a Bandwidth Dimension Ratio (BDR) of 6960, using a tapered microstrip line and employing an improved isolation technique. An inverted T-slot is used in the partial ground plane of the antenna. Isolation is increased up to 25 dB over the operating band (1.6–24.5 GHz) by using a pair of T-shaped stubs and a rectangular strip between them. A detailed analysis of the parameters Envelope Correlation Coefficient (ECC), Diversity Gain (DG), Mean Effective Gain (MEG), Total Active Reflection Coefficient (TARC), isolation between the ports, and Channel Capacity Loss (CCL) is undertaken to investigate the performance of proposed SWB MIMO antenna. A prototype of the proposed design is developed by fabricating on the FR–4 (loss tangent 0.02) dielectric substrate of electrical dimension 0.18λ
0 × 0.14λ
0. The measured parameters are in good agreement with the simulated ones. The proposed antenna focusses on 2.4–2.483 GHz frequency band (Bluetooth) and 3.4–3.6 GHz frequency band with a center frequency of 3.5 GHz (as part of the sub 6 GHz 5G band).
Monitoring imbibition dynamics at tissue level in Norway spruce using X-ray imaging
Authors: Martin Benoît , Colin Julien , Lu Pin , Mounkaila Mahamadou , Casalinho Joel , Perré Patrick , Rémond Romain
Published: August 2021

The study of moisture migration in Norway Spruce may reduce the discrepancy between measurements and simulations of transfers in buildings and thus be helpful for improving their performance and durability. For this purpose, X-ray imaging was used to study moisture migration in Norway spruce during imbibition at tissue level. Moisture content kinetics in earlywood and latewood, based on X-ray attenuation, was observed and measured through rigorous protocol. The imbibition process was studied in both longitudinal and radial directions. The results showed an easier migration of liquid in latewood than in earlywood in the longitudinal uptake. In the radial direction, the impact of compression wood as a barrier and the role of the anatomical structure in the liquid migration were highlighted by the direct visualization of filled tracheids.
COVID-19 and lung pathologies
Authors: Purohit Darshana , Ahirwar Ashok Kumar , Sakarde Apurva , Asia Priyanka , Gopal Niranjan
Published: August 2021

COVID-19 is a global emergency with over 10 million cases and over 500, 000 deaths worldwide. The SARS CoV-2 is a RNA virus belonging to the family coronaviridae. It has high infectivity. The manifestations of the disease range from asymptomatic or mild symptoms to severe pneumonia and ARDS. The CT scan of lung shows consolidation and “Ground Glass Opacities”. The persons with other comorbidities are considered to be at a higher rate of acquiring the infection. Asthma and other allergies have not been identified as major risk factors for COVID-19 as the number of asthmatic patients having COVID-19 is not high enough for it to be considered so. The occurrence of COVID-19 in COPD patients can be related with smoking. The ACE-2 expression in such patients was considerably high. The relation between COVID-19 and Tuberculosis can also be reflected in terms of the stigma associated with diagnosis and treatment of such diseases in some communities, eventually increasing the chances of people's reluctance to seek medical help. Cancer patients are usually more susceptible to infections. Lung cancer is no different. Additionally, lung cancer also has strong association with smoking further increasing the risk. The risk of getting infection and its severity is high for autoimmune disorders as well as fungal infections. Currently there is no definite treatment of COVID-19. However, some of the currently used modalities are hydroxychloroquine and antiviral drugs.
Characterization of the scavenger cell proteome in mouse and rat liver
Authors: Paluschinski Martha , Jin Cheng Jun , Qvartskhava Natalia , Görg Boris , Wammers Marianne , Lang Judith , Lang Karl , Poschmann Gereon , Stühler Kai , Häussinger Dieter
Published: August 2021

The structural-functional organization of ammonia and glutamine metabolism in the liver acinus involves highly specialized hepatocyte subpopulations like glutamine synthetase (GS) expressing perivenous hepatocytes (scavenger cells). However, this cell population has not yet been characterized extensively regarding expression of other genes and potential subpopulations. This was investigated in the present study by proteome profiling of periportal GS-negative and perivenous GS-expressing hepatocytes from mouse and rat. Apart from established markers of GS+ hepatocytes such as glutamate/aspartate transporter II (GLT1) or ammonium transporter Rh type B (RhBG), we identified novel scavenger cell-specific proteins like basal transcription factor 3 (BTF3) and heat-shock protein 25 (HSP25). Interestingly, BTF3 and HSP25 were heterogeneously distributed among GS+ hepatocytes in mouse liver slices. Feeding experiments showed that RhBG expression was increased in livers from mice fed with high protein diet compared to standard chow. While spatial distributions of GS and carbamoylphosphate synthetase 1 (CPS1) were unaffected, periportal areas constituted by glutaminase 2 (GLS2)-positive hepatocytes were enlarged or reduced in response to high or low protein diet, respectively. The data suggest that the population of perivenous GS+ scavenger cells is heterogeneous and not uniform as previously suggested which may reflect a functional heterogeneity, possibly relevant for liver regeneration.
Anti-inflammatory dihydroxanthones from a Diaporthe species
Authors: Rohr Markus , Kiefer Anna Maria , Kauhl Ulrich , Groß Jonathan , Opatz Till , Erkel Gerhard
Published: August 2021

In a search for anti-inflammatory compounds from fungi inhibiting the promoter activity of the small chemokine CXCL10 (Interferon-inducible protein 10, IP-10) as a pro-inflammatory marker gene, the new dihydroxanthone methyl (1R, 2R)-1,2,8-trihydroxy-6-(hydroxymethyl)-9-oxo-2,9-dihydro-1H-xanthene-1-carboxylate (2) and the previously described dihydroxanthone AGI-B4 (1) were isolated from fermentations of a Diaporthe species. The structures of the compounds were elucidated by a combination of one- and two-dimensional NMR spectroscopy, mass spectrometry, and calculations using density functional theory (DFT). Compounds 1 and 2 inhibited the LPS/IFNγ induced CXCL10 promoter activity in transiently transfected human MonoMac6 cells in a dose-dependent manner with IC50 values of 4.1 µM (±0.2 µM) and 1.0 µM (±0.06 µM) respectively. Moreover, compounds 1 and 2 reduced mRNA levels and synthesis of pro-inflammatory mediators such as cytokines and chemokines in LPS/IFNγ stimulated MonoMac6 cells by interfering with the Stat1 and NFκB pathway.
Der dritte Mann. Versöhnungen von Aristokraten in der späten Republik
Authors: Timmer Jan Martin
Published: August 2021

Die Versöhnung von Aristokraten war in der römischen Republik von besonderer Bedeutung. Auf der einen Seite lieferten sie sich einen erbitterten Konkurrenzkampf um Ämter und Prestige bei gleichzeitig hoher Bedeutung persönlicher Ehre, auf der anderen Seite war das politische System auf weitgehende Einmütigkeit der relevanten Akteure angewiesen. Der zentrale Mechanismus war die Versöhnung der Konfliktparteien über Dritte. Dabei handelt es sich um ein Phänomen, das aus der Umwelt des Politischen in dieses transferiert wurde, wesentliche Eigenschaften dabei beibehielt, sich aber zugleich weiterentwickelte und mit der Ausbildung von Rollen, definierter Referenzgruppen und spezifischer Argumente den Bedürfnissen des politischen Systems anpaßte.
Tatort Tana. Die Rolle Lateineuropas in der Sklavenökonomie des Schwarzmeerraums (ca. 1300–1500)
Authors: Schiel Juliane
Published: August 2021

Die lateineuropäische Haussklaverei des Spätmittelalters gilt in der Forschung gemeinhin als ein Nebenprodukt konvergierender wirtschaftlicher, diplomatischer und militärstrategischer Interessen zwischen Ägypten, Genua und der Goldenen Horde in Zentralasien und Nahost. Als die italienischen Seehandelsschiffe die Knaben und Männer der Sklavenmärkte von Tana und Kaffa für die mamlukische Armee über das Mittelmeer verschifften, gelangten deren Mütter und Schwestern zunehmend auf demselben Wege als Haussklavinnen nach Südeuropa. Während man die Lebenssituation dieser jungen Frauen ab dem Moment, in dem sie in einem lateinischen Handels- oder Notariatsregister als „schiava“ geführt werden, relativ gut erschließen kann, lässt die Überlieferung für die Zeit davor – den Moment des Sklavewerdens – kaum Verlässliches zu. Der vorliegende Aufsatz widmet sich dieser Leerstelle. Durch die Identifizierung und mikrohistorische Auswertung fragmentarischer Überlieferung wird ein Möglichkeitsraum entworfen, innerhalb dessen Menschen zu Sklaven/-innen der Lateiner werden konnten. Dabei wird gezeigt, dass die Lateiner nicht nur Lieferanten und sekundäre Abnehmer einer bestehenden Sklavenökonomie waren, sondern auch selbst als Versklavende auftraten. Die Logiken der Gewalt ebenso wie die Tausch- und Geschenkkultur der Frontiergesellschaft des Schwarzmeerraums existierten nicht losgelöst vom Machtapparat der expandierenden Seehandelsimperien Lateineuropas; sie waren eine wichtige Voraussetzung ihres Erfolgs.
Die Geburt der Wohngemeinschaft. Die Saint-Simonisten in Paris und Ménilmontant, 1825–1835
Authors: Barth Volker
Published: August 2021

Der Beitrag untersucht die Entstehung alternativer Lebensformen in den 1820er und 1830er Jahren. Als Untersuchungsgegenstand dienen die verschiedenen Wohnexperimente der französischen Saint-Simonisten in Paris und insbesondere deren gemeinschaftliche Unterkunft in Ménilmontant. Es wird gefragt, warum bereits im frühen 19. Jahrhundert innovative Formen des Wohnens als Keimzellen einer neuen Gesellschaft imaginiert wurden und mit welchen kulturellen, sozialen und politischen Zielsetzungen Alltagspraktiken neu organisiert und ideologisch überhöht wurden. Dazu werden zunächst die Entstehung und Radikalisierung der saint-simonistischen Gemeinschaft erläutert, bevor auf öffentliche Diskurse und staatliche Repressionen eingegangen wird. Diese werden im letzten Teil in einen analytischen Bezug zu den Wohngemeinschaften der 1960er Jahre gesetzt.
In der Schwebe. Markt, Staat und Wettbewerb in Deutschland zwischen 1918 und 1948
Authors: Hederer Franz , Priemel Kim Christian
Published: August 2021

Die erste Hälfte des 20. Jahrhunderts ist gerade in Deutschland von markanten politischen und ideologischen Brüchen gekennzeichnet, die sich tief in das kollektive Gedächtnis eingegraben haben, ohne aber unsere Wahrnehmung von Ökonomie und Staat im gleichen Zeitraum nachhaltig zu prägen. In vorliegendem Beitrag wird für einen Perspektivwechsel plädiert, um mittelfristig persistente Strukturen in den Debatten um das vermeintlich richtige Verhältnis von Markt, Staat und Wettbewerb freizulegen. Erkennbar werden so die Konturen einer „unausgetragenen“ Wirtschaftsordnung, um deren Ausrichtung zwischen den 1910er Jahren und den späten 1940ern erbittert gerungen wurde, und die doch stets in der Schwebe blieb. Die zeitgenössischen Kontroversen lassen sich als Suche nach einem kohärenten Prinzip interpretieren, die erst in der frühen Bundesrepublik ihren einstweiligen Abschluss fand. Denn die zunächst ambitionierten, dann pragmatischen Versuche in der Weimarer Republik, die Beziehungen der privaten Marktakteure zueinander und zum Gemeinwesen auf eine neue Grundlage zu stellen, vermochten im Spannungsfeld von ökonomischen Problemen und tagespolitischen Nöten nur eine fragile, beständig herausgeforderte Struktur auszuformen. Die Lösungsansätze dieses wirtschafts- und verfassungsrechtlichen Ordnungsproblems, das durch die Delegitimierung des klassisch-liberalen wie des zwangswirtschaftlichen Paradigmas infolge des Ersten Weltkrieges aufgeworfen worden war, blieben somit bis in die zweite Nachkriegszeit nur tentativ, ehe sich mit ordoliberalen Ansätzen, durch inhaltliche Häutungen, personale Kontinuitäten und historische Kontingenzen bedingt, ein neues Prinzip durchzusetzen vermochte – und schon bald verklärt wurde.
Diskurs, Narrativ, Sonderweg, Hitler, Turn. Konjunkturen geschichtswissenschaftlicher Begriffe im „Clio Viewer“
Authors: Wehrheim Lino , Jopp Tobias A. , Spoerer Mark
Published: August 2021

Auf Anregung einer (nichtrepräsentativen) Twitterumfrage unter Historikerinnen und Historikern möchten wir in diesem Beitrag ein von uns zusammengetragenes Korpus an Aufsätzen aus elf geschichtswissenschaftlichen Fachjournalen vorstellen und anhand einiger Beispiele illustrieren, wie sich der Gebrauch verschiedener prägnanter geschichtswissenschaftlicher (Leit‑) Begriffe seit 1950 verändert hat. Das Ziel ist nicht, eine „digitale Begriffsgeschichte“ verschiedener Begriffe vorzulegen oder gar Rückschlüsse auf die Entwicklung des Fachs zu ziehen. Vielmehr geht es uns darum, die vorgeschlagenen und um eigene Kandidaten ergänzten Begriffe und deren Konjunkturen zu präsentieren, um so eine Grundlage für eine weitergehende Diskussion digitalhistorischer Methoden und des Nutzens eines „Clio Viewers“ zu legen. Besonderes Augenmerk richten wir auf die Erörterung der mit dem Einsatz einfacher Stichwortsuchen verbundenen methodischen Fallstricke.
CFD-based simulation to reduce greenhouse gas emissions from industrial plants
Authors: Sarjito  , Elveny Marischa , Jalil Abduladheem Turki , Davarpanah Afshin , Alfakeer Majda , Awadh Bahajjaj Aboud Ahmed , Ouladsmane Mohamed
Published: August 2021

Greenhouse gas (GHG) pollution is considered one of the challenging concerns in industrial plants, and to emit the appropriate designation in nitrogen oxide reduction, it is required to implement proper numerical simulation procedures. In this study, ANSYS Fluent® software is used as dynamic software to solve heat and mass flow transfer numerically by considering non-structured networks for complex geometries. Dry nitrogen oxide burners have an additional thermocouple to provide an extra fuel pathway to combine with air. Then, standard K-ε is used in the numerical simulations to calculate thermal efficiency in combustion processes for turbulent flow regimes. It can cause the removal of 50% of nitrogen oxide into the atmosphere. Furthermore, by the increase of temperature, nitrogen oxide concentration has been increased in the system. After 1975 K, Fuel has been changed to dry fuel, and therefore nitrogen oxide concentration increased because the steam can provide a relatively non-combustible compound increase than fuel. On the other hand, regarding the water volume increase at inlet steam, nitrogen oxide volume percentage has been decreased dramatically, especially in the first periods of water volume increase. Consequently, when the steam percentage is increased instead of water, nitrogen oxide reduction is increased. Moreover, our simulation results have a proper match with Gibbs energy equilibrium.
Beneficiation of phosphate-siliceous slates via acetic acid
Authors: Raiymbekov Yerkebulan , Besterekov Uilesbek , Abdurazova Perizat , Nazarbek Ulzhalgas , Kambarova Galiya , Petropavlovskiy Igor
Published: August 2021

Low grade phosphate-siliceous slates dump samples (about 11.98% P2O5) from Zhanatas deposit, Karatau basin, Kazakhstan were subjected to upgrading in the present study. The suggested upgrading route was to get rid of most of the inorganic carbonates via leaching using organic acids like acetic acid. The effect of leaching temperature, dissolution time, and solid/liquid ratio were studied as the main determental working parameters. It was concluded that a concentrate product containing about 21% P2O5 was produced after leaching with acetic acid at optimum conditions: 30 C0, 15 min, and 3:1 liquid/solid ratio. The calculated apparent activation energy of the leaching process showed that the process took place in the intra-diffusion region.