Search results for: bonding mechanisms

Authors: Mona T. Kashef, Omneya M. Helmy

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Multidrug resistant (MDR) bacteria have become a significant public health threat. The prevalence rates, of Gram negative MDR bacteria, are in continuous increase. However, few data are available about these resistant strains. Since, third generation cephalosporins are one of the most commonly used antimicrobials, we set out to investigate the prevalence, different mechanisms and clonal relatedness of multidrug resistance among third generation resistant Gram negative clinical isolates. A total of 114 Gram negative clinical isolates, previously characterized as being resistant to at least one of 3rd generation cephalosporins, were included in this study. Each isolate was tested, using Kirby Bauer disk diffusion method, against its assigned categories of antimicrobials. The role of efflux pump in resistance development was tested by the efflux pump inhibitor-based microplate assay using chloropromazine as an inhibitor. Detecting different aminoglycosides, β-lactams and quinolones resistance genes was done using polymerase chain reaction. The genetic diversity of MDR isolates was investigated using Random Amplification of Polymorphic DNA technique. MDR phenotype was detected in 101 isolates (89%). Efflux pump mediated resistance was detected in 49/101 isolates. Aminoglycosides resistance genes; armA and aac(6)-Ib were detected in one and 53 isolates, respectively. The aac(6)-Ib-cr allele, that also confers resistance to floroquinolones, was detected in 28/53 isolates. β-lactam resistance genes; blaTEM, blaSHV, blaCTX-M group 1 and group 9 were detected in 52, 29, 61 and 35 isolates, respectively. Quinolone resistance genes; qnrA, qnrB and qnrS were detectable in 2, 14, 8 isolates respectively, while qepA was not detectable at all. High diversity was observed among tested MDR isolates. MDR is common among 3rd generation cephalosporins resistant Gram negative bacteria, in Egypt. In most cases, resistance was caused by different mechanisms. Therefore, new treatment strategies should be implemented.

Keywords: gram negative, multidrug resistance, RAPD typing, resistance genes

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Authors: Rong Sun, Laihong Shen

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La-based perovskite oxygen carriers, especially the doped-La(M)FeO₃, showed excellent performances during chemical looping processes. However, the mechanisms of the undoped and doped La(M)FeO₃ are not clear at present, making the mechanisms clear may help the development of chemical looping technologies. In this paper, the method based on the density function theory (DFT) was used to analysis the influence of Ca, Sr, and Ba doping of La on the electronic structure, while the CO oxidation mechanisms on the surface of LaFeO₃ and Ca-doped LaFeO₃ oxygen carriers were also analyzed. The results showed that the band gap was decreased by the doping of low valence. While the doping of low valence element Ca, Sr, and Ba at La site simultaneously resulted to the moving of the valence band toward high energy and made the valence band cross the Fermi energy level. This was resulted from the holes generated by divalent ion substitution. The holes can change the total magnetization from antiferromagnet to weakly ferromagnetism. The calculation results about the formation of oxygen vacancy showed that substitutions of Ca, Sr, and Ba caused a large drop in oxygen vacancy formation energy, indicating that the bulk oxygen transport was improved. Based on the optimized bulk of the undoped and Ca-doped LaFeO₃(010) surface, the CO adsorption was analyzed. The results indicated that the adsorption energy increased by divalent ion substitution, meaning that the adsorption stability decreased. The results can provide a certain theoretical basis for the development of perovskite oxides in chemical looping technologies.

Keywords: chemical looping technologies, lanthanum ferrate (LaFeO₃), divalent ion substitution, CO oxidation

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Authors: Allam Srinivasa Rao, Ch. Annapurna Devi, G. Vijaya Prakash

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A new-fangled series of white light emitting 1 mol% of Dy3+ ions doped Single-Alklai and Mixed-Alkai fluoro tungstunate tellurite glasses have been prepared using melt quenching technique and their spectroscopic behaviour was investigated by studying XRD, optical absorption, photoluminescence and lifetime measurements. The bonding parameter studies reveal the ionic nature of the Dy-O bond in the present glasses. From the absorption spectra, the Judd–Ofelt (J-O) intensity parameters have been determined which are used to explore the nature of bonding and symmetry orientation of the Dy–ligand field environment. The evaluated J-O parameters (Ω_4>Ω_2>Ω_6) for all the glasses are following the same trend. The photoluminescence spectra of all the glasses exhibit two intensified peaks in blue and Yellow regions corresponding to the transitions 4F9/2→6H15/2 (483 nm) and 4F9/2→6H13/2 (575 nm) respectively. From the photoluminescence spectra, it is observed that the luminescence intensity is maximum for Dy3+ ion doped potassium combination of fluoro tungstunate tellurite glass (TeWK: 1Dy). The J-O intensity parameters have been used to determine the various radiative properties for the different emission transitions from the 4F9/2 fluorescent level. The highest emission cross-section and branching ratio values observed for the 4F9/2→6H15/2 and 4F9/2→6H13/2 transitions suggest the possible laser action in the visible region from these glasses. By using the experimental lifetimes (τ_exp) measured from the decay spectral features and radiative lifetimes (τ_R), the quantum efficiencies (η) for all the glasses have been evaluated. Among all the glasses, the potassium combined fluoro tungstunate tellurite (TeWK:1Dy) glass has the highest quantum efficiency (94.6%). The CIE colour chromaticity coordinates (x, y), (u, v), colour correlated temperature (CCT) and Y/B ratio were also estimated from the photoluminescence spectra for different compositions of glasses. The (x, y) and (u, v) chromaticity colour coordinates fall within the white light region and the white light can be tuned by varying the composition of the glass. From all these studies, we are suggesting that the 1 mol% of Dy3+ ions doped TeWK glass is more suitable for lasing and White-LED applications.

Keywords: dysprosium, Judd-Ofelt parameters, photo luminescence, tellurite glasses

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Authors: A. Paz, M. Khadka, N. Veeramisti, B. Morris

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There is a continuous large number of crashes involving pedestrians in Nevada despite the numerous safety mechanisms currently used at roadway crossings. Hence, additional as well as more effective mechanisms are required to reduce crashes in Las Vegas, in particular, and Nevada in general. A potential mechanism to reduce conflicts between pedestrians and vehicles is a High-intensity Activated crossWalK (HAWK) signal. This study evaluates the effects of such signals at a particular site in Las Vegas. Video data were collected using two cameras, facing the eastbound and westbound traffic. One week of video data before and after the deployment of the signal were collected to capture the behavior of both pedestrians and drivers. T-test analyses of pedestrian waiting time at the curb, curb-to-curb crossing time, total crossing time, jaywalking events, and near-crash events show that the HAWK system provides significant benefits.

Keywords: pedestrian crashes, HAWK signal, traffic safety, pedestrian danger index

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Authors: Haibin Zhou, Pingping Yao, Kunyang Fan

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Copper-based sintered friction materials are widely used in the brake system of different applications such as engineering machinery or high-speed train, due to the excellent mechanical, thermal and tribological performance. Considering the diversity of the working conditions of brake system, it is necessary to identify well and understand the tribological performance and wear mechanisms of friction materials for different conditions. Fe has been a preferred reinforcement for copper-based friction materials, due to its ability to improve the wear resistance and mechanical properties of material. Wear map is well accepted as a useful research method for evaluation of wear performances and wear mechanisms over a wider range of working conditions. Therefore, it is significantly important to construct a wear map which can give out the effects of work condition and Fe reinforcement on tribological performance of Cu-based friction materials. In this study, the copper-based sintered friction materials with the different addition of Fe reinforcement (0-20 vol. %) were studied. The tribological tests were performed against stainless steel in a ring-on-ring braking tester with varying braking energy density (0-5000 J/cm2). The linear wear and friction coefficient were measured. The worn surface, cross section and debris were analyzed to determine the dominant wear mechanisms for different testing conditions. On the basis of experimental results, the wear map and wear mechanism map were established, in terms of braking energy density and the addition of Fe. It was found that with low contents of Fe and low braking energy density, adhesive wear was the dominant wear mechanism of friction materials. Oxidative wear and abrasive wear mainly occurred under moderate braking energy density. In the condition of high braking energy density, with both high and low addition of Fe, delamination appeared as the main wear mechanism.

Keywords: Cu-based friction materials, Fe reinforcement, wear map, wear mechanism

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Authors: Hanna Faron, Wojciech Marcinkowski, Daniel Prusak, Władysław Hamiga

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Interest in composite materials comes out of two basic premises: their supreme mechanical and strength properties,combined with a small specific weight. Origin and evolution of modern composite materials bonds with development of manufacturing of synthetic fibers, which have begun during Second World War. Main condition to achieve intended properties of composite materials is proper bonding of reinforcing layer with appropriate adhesive in manufacturing process. It is one of the fundamental quality evaluation criterion of fabrication processes.

Keywords: SAE, formula student, composite materials, carbon fiber, Aramid fiber, hot wire cutter

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Authors: A. Satty, H. Mwambi

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Much clinical trials data-based research are characterized by the unavoidable problem of dropout as a result of missing or erroneous values. This paper aims to review some of the various techniques to address the dropout problems in longitudinal clinical trials. The fundamental concepts of the patterns and mechanisms of dropout are discussed. This study presents five general techniques for handling dropout: (1) Deletion methods; (2) Imputation-based methods; (3) Data augmentation methods; (4) Likelihood-based methods; and (5) MNAR-based methods. Under each technique, several methods that are commonly used to deal with dropout are presented, including a review of the existing literature in which we examine the effectiveness of these methods in the analysis of incomplete data. Two application examples are presented to study the potential strengths or weaknesses of some of the methods under certain dropout mechanisms as well as to assess the sensitivity of the modelling assumptions.

Keywords: incomplete longitudinal clinical trials, missing at random (MAR), imputation, weighting methods, sensitivity analysis

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Authors: Kindeye Fenta Mekonnen, Alagaw Ababu Kifle

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The failure of international responses to armed conflict to address local preconditions for national stability has recently attracted what has been called the ‘local turn’ in peace building. This ‘local turn’ in peace building amplified a renewed interest in traditional/indigenous methods of conflict resolution, a field that has been hitherto dominated by anthropologists with their focus on the procedures and rituals of such approaches. This notwithstanding, there is still limited empirical work on the relevance of traditional methods of conflict resolution to end localized conflicts vis-à-vis hybrid and modern approaches. The few exceptions to this generally draw their conclusion from very few (almost all successful) cases that make it difficult to judge the validity and cross-case application of their results. This paper seeks to fill these gaps by undertaking a quantitative analysis of the trend and applications of different communal conflict resolution initiatives, their potential to usher in long-term peace, and the extent to which their outcomes are influenced by the intensity and scope of a conflict. The paper makes the following three tentative conclusions. First, traditional mechanisms and traditional actors still dominate the communal conflict resolution landscape, either individually or in combination with other methods. Second, traditional mechanisms of conflict resolution tend to be more successful in ending a conflict and preventing its re-occurrence compared to hybrid and modern arrangements. This notwithstanding and probably due to the scholarly call for local turn in peace building, contemporary communal conflict resolution approaches are becoming less and less reliant on traditional mechanisms alone and (therefore) less effective. Third, there is yet inconclusive evidence on whether hybridization is an asset or a liability in the resolution of communal conflicts and the extent to which this might be mediated by the intensity of a conflict.

Keywords: traditional conflict resolution, hybrid conflict resolution, communal conflict, relevance, conflict intensity

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Authors: Tong-Chien Wu, Ching-Liang Hsieh, Yi-Wen Lin

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There are accumulating evidences surrounding the therapeutic effect of electroacupuncture (EA). Local EA can reliably attenuate inflammatory pain in mouse with unclear mechanisms. However, the effect of EA on distal and contralateral acupoint for pain control has been rarely studied and the result was controversial. Here in our study, we found that inflammatory hindpaw pain in mouth, which was induced by injecting the complete Freund’s adjuvant (CFA) 2 days ago can be alleviated immediately after 2Hz 15mins EA treatment at contralateral forefoot acupoint LI4 through both mechanic and thermal behavior test, while sham acupoint group is not. The efficacy was observed to be more obvious after the second round of EA treatment on the following day. This analgesic effect is produced by applying EA to a site remote from the painful area. The present study provides a powerful experimental animal model that can be used for investigating the unique physiological mechanisms involved in acupuncture analgesia.

Keywords: remote electroacupuncture, distal EA, pain control, anti-inflammation

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Authors: Jing Li, Li Jin, Fulin Wang, Jie Dong, Wenjiang Ding

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Mg-Li dual-phase alloy exhibits better combination of yield strength and elongation than the Mg single-phase alloy. To exploit its deformation behavior, the deformation mechanisms of Mg-2Gd alloy with or without Li addition, i.e., Mg-6Li-2Gd and Mg-2Gd alloy, have been studied at both microscale and mesoscale. EBSD-assisted slip trace, twin trace, and texture evolution analysis show that the α-Mg phase of Mg-6Li-2Gd alloy exhibits different microscopic deformation mechanisms with the Mg-2Gd alloy, i.e., mainly prismatic slip in the former one, while basal slip, prismatic slip and extension twin in the latter one. Further Schmid factor analysis results attribute this different intra-phase deformation mechanisms to the higher critical resolved shear stress (CRSS) value of extension twin and lower ratio of CRSSprismatic /CRSSbasal in the α-Mg phase of Mg-6Li-2Gd alloy. Additionally, Li addition can induce dual-phase microstructure in the Mg-6Li-2Gd alloy, leading to the formation of hetero-deformation induced (HDI) stress at the mesoscale. This can be evidenced by the hysteresis loops appearing during the loading-unloading-reloading (LUR) tensile tests and the activation of multiple slip activity in the α-Mg phase neighboring β-Li phase. The Mg-6Li-2Gd alloy shows higher yield strength is due to the harder α-Mg phase arising from solid solution hardening of Li addition, as well asthe strengthening of soft β-Li phase by the HDI stress during yield stage. Since the strain hardening rate of Mg-6Li-2Gd alloy is lower than that of Mg-2Gd alloy after ~2% strain, which is partly due to the weak contribution of HDI stress, Mg-6Li-2Gd alloy shows no obvious increase of uniform elongation than the Mg-2Gd alloy.But since the β-Li phase is effective in blunting the crack tips, the Mg-6Li-2Gd alloy shows ununiform elongation, which, thus, leads to the higher total elongation than the Mg-2Gd alloy.

Keywords: Mg-Li-Gd dual-phase alloy, phase boundary, HDI stress, dislocation slip activity, mechanical properties

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Authors: Ehsan Alishahi, Chuang Deng

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Materials with microstructural heterogeneity have recently attracted dramatic attention in the materials science community. Although most of the metals are identified as crystalline, the new class of amorphous alloys, sometimes are known as metallic glasses (MGs), exhibited remarkable properties, particularly high mechanical strength and elastic limit. The unique properties of MGs led to the wide range of studies in developing and characterizing of new alloys or composites which met the commercial desires. In spite of applicable properties of MGs, commercializing of metallic glasses was limited due to a major drawback, the lack of ductility and sudden brittle failure mode. Hence, crystalline-amorphous (C-A) composites were introduced almost in 2000s as a toughening strategy to improve the ductility of MGs. Despite the considerable progress reported in previous studies, there are still challenges in both synthesis and characterization of metallic C-A composites. In this study, accumulative roll bonding (ARB) was used to synthesize bulk crystalline-amorphous composites starting from crystalline Cu-Zr multilayers. Due to the severe plastic deformation state, new CuZr phases were formed during the rolling process which was reflected in SEM-EDS analysis. EDS elemental analysis showed the variation in the composition of CuZr phases such as 38-62, 50-50 to 68-32 at Cu-Zr % respectively. Moreover, TEM with electron diffraction analysis indicated the presence of both crystalline and amorphous structures for the new formed CuZr phases. In addition to the microstructural analysis, the mechanical properties of the synthesized composites were studied using the nanoindentation technique. Hysitron Nanoindentation instrument was used to conduct nanoindentation tests with cube corner tip. The maximum load of 5000 µN was applied in load control mode to measure the elastic modulus and hardness of different phases. The trend of results indicated three distinct regimes of hardness and elastic modulus including pure Cu, pure Zr, and new formed CuZr phases. More specifically, pure Cu regions showed the lowest values for both nanoindentation hardness and elastic modulus while the CuZr phases take the highest values. Consequently, pure Zr was placed in the intermediate range which is harder than pure Cu but softer than CuZr phases. In overall, it was found that CuZr phases with higher hardness were nucleated during ARB process as a result of mechanical alloying phenomenon.

Keywords: ARB, crystalline-amorphous composites, mechanical alloying, nanoindentation hardness

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Authors: Luis Gimeno, Rosmeri da Rocha, Raquel Nieto, Tercio Ambrizzi, Alex Ramos, Anita Drumond

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The transport of moisture from oceanic sources to the continents represents the atmospheric branch of the water cycle, forming the connection between evaporation from the ocean and precipitation over the continents. In this regard two large scale dynamical/meteorological structures appear to play a key role, namely Low Level Jet (LLJ) systems and Atmospheric Rivers (ARs). The former are particularly important in tropical and subtropical regions; the latter is mostly confined to extratropical regions. A key question relates to the anomalies in the transport of moisture observed during natural hazards related to extremes of precipitation (i.e., drought or wet spells). In this study we will be focused on these two major atmospheric moisture transport mechanisms (LLJs and ARs) and its role in precipitation extreme events (droughts and wet spells) in the Amazonia paying particular attention to i) intensification (decreasing) of moisture transport by them and its role in wet spells (droughts), and ii) changes in their positions and occurrence with associated flooding and wet spells.

Keywords: droughts, wet spells, amazonia, LLJs, atmospheric rivers

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Authors: Marianne Simons, Sinan Kurt, Marjolein Stefens, Kai Karos, Johan Lataster

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As cultural diversity within older populations in European countries increases, the role of cultural background should be taken account of in aging studies. Bonding social capital (BSC), containing someone’s socio-emotional resources, is recognised as an important ingredient for wellbeing in old age and found to be associated with someone’s cultural background. The current study examined the association between BSC, loneliness and wellbeing in a sample including older Turkish migrants with a collectivistic cultural background and native Dutch older adults, both living in the Netherlands, characterised by an individualistic culture. A sample of 119 Turkish migrants (64.7% male; age 65-87, M(SD)=71.13(5.04) and 124 native Dutch adults (32.3% male, age 65-94, M(SD)= 71.9(5.32) filled out either an online or printed questionnaire measuring BSC, psychological, social and emotional well-being, loneliness and relevant demographic covariates. Regression analysis - including confounders age, gender, level of education, physical health and relationship - showed positive associations between BSC and respectively emotional, social and psychological well-being and a negative association with loneliness in both samples. Moderation analyses showed that these associations were significantly stronger for the Turkish older migrants than for their native peers. Measurement invariance analysis indicated partial metric invariance for the measurement of BSC and loneliness and non-invariance for wellbeing, calling for caution comparing means between samples. The results stress the importance of BSC for wellbeing of older migrants from collectivistic cultures living in individualistic countries. Previous research, shows a trend of older migrants displaying lower levels of BSC as well as associated variables, such as education, physical health, and financial income. This calls for more research of the interplay between demographic and psychosocial factors restraining mental wellbeing of older migrant populations. Measurement invariance analyses further emphasize the importance of taking cultural background into account in positive aging studies.

Keywords: positive aging, cultural background, wellbeing, social capital, loneliness

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Authors: Han-Qin Zheng, Yi-Fan Chiang-Hsieh, Chia-Hung Chien, Wen-Chi Chang

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As the most important non-vascular plants, algae have many research applications, including high species diversity, biofuel sources, adsorption of heavy metals and, following processing, health supplements. With the increasing availability of next-generation sequencing (NGS) data for algae genomes and transcriptomes, an integrated resource for retrieving gene expression data and metabolic pathway is essential for functional analysis and systems biology in algae. However, gene expression profiles and biological pathways are displayed separately in current resources, and making it impossible to search current databases directly to identify the cellular response mechanisms. Therefore, this work develops a novel AlgaePath database to retrieve gene expression profiles efficiently under various conditions in numerous metabolic pathways. AlgaePath, a web-based database, integrates gene information, biological pathways, and next-generation sequencing (NGS) datasets in Chlamydomonasreinhardtii and Neodesmus sp. UTEX 2219-4. Users can identify gene expression profiles and pathway information by using five query pages (i.e. Gene Search, Pathway Search, Differentially Expressed Genes (DEGs) Search, Gene Group Analysis, and Co-Expression Analysis). The gene expression data of 45 and 4 samples can be obtained directly on pathway maps in C. reinhardtii and Neodesmus sp. UTEX 2219-4, respectively. Genes that are differentially expressed between two conditions can be identified in Folds Search. Furthermore, the Gene Group Analysis of AlgaePath includes pathway enrichment analysis, and can easily compare the gene expression profiles of functionally related genes in a map. Finally, Co-Expression Analysis provides co-expressed transcripts of a target gene. The analysis results provide a valuable reference for designing further experiments and elucidating critical mechanisms from high-throughput data. More than an effective interface to clarify the transcript response mechanisms in different metabolic pathways under various conditions, AlgaePath is also a data mining system to identify critical mechanisms based on high-throughput sequencing.

Keywords: next-generation sequencing (NGS), algae, transcriptome, metabolic pathway, co-expression

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Authors: Andrei Bogdan Stanescu, Robert Stana

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Creating private and secure communication channels between employees has become a critical aspect in order to ensure organizational integrity and avoid leaks of sensitive information. With the widespread use of modern methods of disrupting communication between users, real use-cases of advanced encryption mechanisms have emerged to avoid cyber-attackers that are willing to intercept private conversations between critical employees in an organization. This paper aims to present a custom implementation of a messaging application named “Whisper” that uses end-to-end encryption (E2EE) mechanisms and blockchain-related components to protect sensitive conversations and mitigate the risks of information breaches inside organizations. The results of this research paper aim to expand the areas of applicability of E2EE algorithms and integrations with private blockchains in chat applications as a viable method of enhancing intra-organizational communication privacy.

Keywords: end-to-end encryption, mobile communication, cryptography, communication security, data privacy

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Authors: Aliyah Penn, Vasiliki Machairaki, Constance Smith-hicks, Sarven Sabunciyan, Lena Smirnova

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Rare neurodevelopmental disorders (RNDDs) encompass a spectrum of conditions affecting a minority of the global population yet pose significant challenges due to their heterogeneity and limited understanding. Among these disorders, SYNGAP1 mutations contribute to a range of cognitive impairments, autism spectrum disorder (ASD), and epilepsy. Despite its rarity, SYNGAP1-Intellectual Disability disorder manifests with varying severity, underscoring the need for improved insights into their underlying biological mechanisms. This research project aims to elucidate the molecular pathways driving the heterogeneous disease severity observed in individuals with SYNGAP1 mutations. Employing a multi-faceted approach, we first characterize SYNGAP1-induced pluripotent stem cells (iPSCs) and iPSC-derived brain organoids, comparing them with familial neurotypically-developed (NTD) controls. Subsequently, we identify molecular signatures of intellectual disability (ID) and epilepsy using RNA sequencing, shedding light on the pathological mechanisms underlying these conditions. Finally, we evaluate and establish a SYNGAP1 seizure model, leveraging MaxWell high-density micro-electrode array (HD-MEA) recordings to assess electrical activity and synaptic function in SYNGAP-ID patients with different intensity of seizures. This comprehensive approach aims to enhance our understanding of SYNGAP1-related disorders and pave the way for personalized treatment strategies tailored to individual patients.

Keywords: SYNGAP, autism, organoids, neurodevelopment

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Authors: Y. Landkocz, C. Lepers, P.J. Martin, B. Fougère, F. Roy Saint-Georges. A. Verdin, F. Cazier, F. Ledoux, D. Courcot, F. Sichel, P. Gosset, P. Shirali, S. Billet

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In 2013, the International Agency for Research on Cancer (IARC) classified air pollution and fine particles as carcinogenic to humans. Causal relationships exist between elevated ambient levels of airborne particles and increase of mortality and morbidity including pulmonary diseases, like lung cancer. However, due to a double complexity of both physicochemical Particulate Matter (PM) properties and tumor mechanistic processes, mechanisms of action remain not fully elucidated. Furthermore, because of several common properties between air pollution PM and tobacco smoke, like the same route of exposure and chemical composition, potential mechanisms of synergy could exist. Therefore, smoking could be an aggravating factor of the particles toxicity. In order to identify some mechanisms of action of particles according to their size, two samples of PM were collected: PM0.03 2.5 and PM0.33 2.5 in the urban-industrial area of Dunkerque. The overall cytotoxicity of the fine particles was determined on human bronchial cells (BEAS-2B). Toxicological study focused then on the metabolic activation of the organic compounds coated onto PM and some genetic and epigenetic changes induced on a co-culture model of BEAS-2B and alveolar macrophages isolated from bronchoalveolar lavages performed in smokers and non-smokers. The results showed (i) the contribution of the ultrafine fraction of atmospheric particles to genotoxic (eg. DNA double-strand breaks) and epigenetic mechanisms (eg. promoter methylation) involved in tumor processes, and (ii) the influence of smoking on the cellular response. Three main conclusions can be discussed. First, our results showed the ability of the particles to induce deleterious effects potentially involved in the stages of initiation and promotion of carcinogenesis. The second conclusion is that smoking affects the nature of the induced genotoxic effects. Finally, the in vitro developed cell model, using bronchial epithelial cells and alveolar macrophages can take into account quite realistically, some of the existing cell interactions existing in the lung.

Keywords: air pollution, fine and ultrafine particles, genotoxic and epigenetic alterations, smoking

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Authors: Linda Frazer

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A pluralistic methodology focuses on promoting an understanding that an alternative juridical framework for the regulation of transnational business negotiations (TBN) between private business parties is fundamentally required. This paper deals with the evolving assessment of the doctoral research of the author which demonstrated that due to insufficient juridical tools, negotiations are commonly misunderstood within the complexity of pluralistic and conflicting legal regimes. This inadequacy causes uncertainty in the enforcement of legal remedies, leaving business parties surprised. Consequently, parties cannot sufficiently anticipate when and how legal rights and obligations are created, often counting on oral or incomplete agreements which may lead to the misinterpretation of the extent of their legal rights and obligations. This uncertainty causes threats to business parties for fear of creating unintended legal obligations or, conversely, that law will not enforce intended agreements for failure to pass the tests of contractual validity. A need to find a manner to set default standards of communications and standards of conduct to monitor our evolving global trade would aid law to provide the security, predictability and foreseeability during alternative dispute resolution required by TBN parties. The conclusion of this study includes a proposal of new trade mechanisms, termed 'Bills of Negotiations' (BON) to enhance party autonomy and promote the ability for TBN parties to self-regulate within the boundaries of law. BON will be guided by a secure juridical institutionalized setting that caters to guiding communications during TBN and resolving disputes that arise along the negotiation processes on a fast track basis.

Keywords: alternative resolution disputes, ADR, good faith, good faith, juridical security, legal regulation, trade mechanisms, transnational business negotiations

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Authors: Nurul-Akidah M. Yusak, Rahmah Mohamed, Noor Zuhaira Abd Aziz

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The introduction of degradable plastic materials into agricultural sectors has represented a promising alternative to promote green agriculture and environmental friendly of modern farming practices. Major challenges of developing degradable agricultural films are to identify the most feasible types of degradation mechanisms, composition of degradable polymers and related processing techniques. The incorrect choice of degradable mechanisms to be applied during the degradation process will cause premature losses of mechanical performance and strength. In order to achieve controlled process of agricultural film degradation, the compositions of degradable agricultural film also important in order to stimulate degradation reaction at required interval of time and to achieve sustainability of the modern agricultural practices. A set of photodegradable polyethylene based agricultural film was developed and produced, following the selective optimization of processing parameters of the agricultural film manufacturing system. Example of agricultural films application for oil palm seedlings cultivation is presented.

Keywords: photodegradable polyethylene, plasticulture, processing schemes

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Authors: Omar Ali, Adesh Ramsubhag, Jayaraj Jayaraman

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Seaweed extracts have been reported as plant biostimulants which could be a safer, organic alternative to harsh pesticides. The incentive to use seaweed-based biostimulants is becoming paramount in sustainable agriculture. The current study, therefore, screened a commercial extract of A. nodosum in tomatoes, cultivated in Trinidad to showcase the multiple beneficial effects. Foliar treatment with an A. nodosum commercial extract led to significant increases in fruit yield and a significant reduction of incidence of bacterial spots and early blight diseases under both greenhouse and field conditions. Investigations were carried out to reveal the possible mechanisms of action of this biostimulant through defense enzyme assays and transcriptome profiling via RNA sequencing of tomato. Studies into disease control mechanisms by A. nodosum showed that the extract stimulated the activity of enzymes such as peroxidase, phenylalanine ammonia-lyase, chitinase, polyphenol oxidase, and β-1,3-glucanase. Additionally, the transcriptome survey revealed the upregulation and enrichment of genes responsible for the biosynthesis of growth hormones, defense enzymes, PR proteins and defense-related secondary metabolites, as well as genes involved in the nutrient mobilization, photosynthesis and primary and secondary metabolic pathways. The results of the transcriptome study also demonstrated the cross-talks between growth and defense responses, confirming the bioelicitor and biostimulant value of seaweed extracts in plants. These effects could potentially implicate the benefits of seaweed extract and validate its usage in sustainable crop production.

Keywords: A. nodosum, biostimulants, elicitor, enzymes, growth responses, seaweeds, tomato, transcriptome analysis

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Authors: Bernt O. Myrvold

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Lignosulfonates (LS) find widespread use as dispersants, binders, anti-oxidants, and fillers. In most of these applications LS is used in formulation together with a number of other components. To better understand the interactions between LS and water and possibly other components in a formulation, the Hansen solubility parameters have been determined for some LS. The Hansen solubility parameter splits the total solubility parameter into three components, the dispersive, polar and hydrogen bonding part. The Hansen solubility parameter was determined by comparing the solubility in a number of solvents and solvent mixtures. We have found clear differences in the solubility parameters, with softwood LS being closer to water than hardwood LS.

Keywords: Hansen solubility parameter, lignosulfonate (LS), solubility, solvent

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Authors: Ernest Nweke

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This paper examines the changing trend in ownership of Mongolian companies and how this trend has influenced corporate governance mechanisms in Mongolian companies. A study of this magnitude is essential as it x-rays the systematic transformation of Mongolia’s corporate world from the public to private ownership and the tremendous impact it has had on firm governance mechanisms. Owing to Mongolia’s Soviet past, much of the companies in Mongolia were state-owned, state-directed and state-controlled resulting in serious inefficiencies in these companies. This scenario is antithetical to the economic growth and development of any nation as it is grossly at variance with the fundamental principles of good corporate governance that drive prosperity. Consequently, the Mongolian government has in the past decades fine-tuned government policy to prioritize private ownership, establishing various frameworks that will strengthen corporate governance structures in Mongolia. These efforts have paid off and gone a long way in changing the trend in the ownership of companies in Mongolia reversing the old order. The expectation locally and internationally is that companies in post-socialist Mongolia will be more closely aligned to generally accepted corporate governance mechanisms, generally improving company performance and ultimately returns to shareholders. To achieve the research objectives, the survey research method was employed utilizing a sample of seventy randomly selected listed companies representing 22% of Mongolian Stock Exchange listings. Research hypotheses formulated to guide the conduct of the study were tested using Chi-Square analysis, and results show that ownership trend has drastically changed in the post-socialist Mongolia leading to better corporate governance practices in Mongolian companies. This result has important policy implications.

Keywords: corporate disclosure, free market, private ownership, Mongolia

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Authors: Dante J. Dorantes-González, Aldrin Balsa-Yepes

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Existing learning techniques such as problem-based learning, project-based learning, or case study learning are learning techniques that focus mainly on technical details, but give no specific guidelines on learner’s experience and emotional learning aspects such as arousal salience and valence, being emotional states important factors affecting engagement and retention. Some approaches involving emotion in educational settings, such as social and emotional learning, lack neuroscientific rigorousness and use of specific neurobiological mechanisms. On the other hand, neurobiology approaches lack educational applicability. And educational approaches mainly focus on cognitive aspects and disregard conditioning learning. First, authors start explaining the reasons why it is hard to learn thoughtfully, then they use the method of neurobiological mapping to track the main limbic system functions, such as the reward circuit, and its relations with perception, memories, motivations, sympathetic and parasympathetic reactions, and sensations, as well as the brain cortex. The authors conclude explaining the major finding: The mechanisms of nonconscious learning and the triggers that guarantee long-term memory potentiation. Afterward, the educational framework for practical application and the instructors’ guidelines are established. An implementation example in engineering education is given, namely, the study of tuned-mass dampers for earthquake oscillations attenuation in skyscrapers. This work represents an original learning technique based on nonconscious learning mechanisms to enhance long-term memories that complement existing cognitive learning methods.

Keywords: emotion, emotion-enhanced memory, learning technique, STEM

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Authors: Mina Iskander, Mina Melad, Mourad Yasser, Waleed Abdel Rahim, Amr Mosa, Mohamed El Lahamy, Ezzeldin Sayed-Ahmed, Mohamed Abou-Zeid

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Strengthening of reinforced concrete beams in flexure using externally bonded composite laminate of high tensile strength is easy and of the minimum cost compared to traditional methods such as increasing the concrete section depth or reinforcement that requires formwork and curing which affect the structure usability. One of the main limitations of this technique is debonding of the externally bonded laminate, either by end delamination or by mid-span flexural crack-induced debonding. ACI 440.2-08 suggests that using side-bonded FRP laminate in the flexural strengthening of RC beams may serve to limit the extent and width of flexural cracks. Consequently, this technique may decrease the effect of flexural cracks on initiating the mid-span debonding; i.e. delays the flexural crack-induced debonding. Furthermore, bonding the FRP strips to the side of the beam may offer an attractive, practical solution when the soffit of this beam is not accessible. This paper presents an experimental programme designed to investigate the effect of using externally bonded CFRP laminate on the sides of reinforced concrete beams and compares the results to those of bonding the CFRP laminate to the soffit of the beams. In addition, the paper discusses the effect of using end anchorage by U-wrapping the CFRP strips at their end zones with CFRP sheets for beams strengthened with soffit-bonded and side-bonded CFRP strips. Thus, ten rectangular reinforced concrete beams were tested to failure in order to study the effect of changing the location of the externally bonded laminate on the flexural capacity and ductility of the strengthened beams. Pultruded CFRP strips were bonded to the soffit of the beams or their sides to check the possibility of limiting the flexural cracking in mid-span region, which is the main reason for mid-span debonding. Pre-peg CFRP sheets were used near the support as U-wrap for the beam to act as an end-anchorage for the externally bonded strips in order to delay/prevent the end delamination. Strength gains of 38% and 43% were recorded for the soffit-bonded and the side-bonded composite strips with end U-wrapped sheets, respectively. Furthermore, beams with end sheets applied as an end anchorage showed higher ductility than those without these sheets.

Keywords: flexural strengthening, externally bonded CFRP, side-bonded CFRP, CFRP laminates

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Authors: Ernest Nweke

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The work of Professional Accountants and Corporate governance are synonymous and cannot be divorced from each other. Organizations, profit and non-profit alike cannot implement sound corporate practices without inputs from Professional Accountants. In today’s dynamic corporate world, good corporate governance practice is a sine qua non. More so, following the corporate failures of the past decades like Enron and WorldCom, governments around the world, including Mongolia are becoming more proactive in ensuring sound corporate governance mechanisms. In the past fifteen years, the Mongolian government has taken several measures to establish and strengthen internal corporate governance structures in firms. This paper highlights the role of professional accountants and auditors play in ensuring that good corporate governance mechanisms are entrenched in listed companies in Mongolia. Both primary and secondary data are utilized in this research. In collection of primary data, Delphi method was used, securing responses from only knowledgeable senior employees, top managers, and some CEOs. Using this method, a total of 107 top-level company employees and executives randomly selected from 22 companies were surveyed; maximum of 5 and minimum of 4 from each company. These companies cut across several sectors. It was concluded that Professional Accountants play key roles in setting and maintaining firm governance. They do this by ensuring full compliance with all the requirements of good and sound corporate governance, establishing reporting, monitoring and evaluating standards, assisting in the setting up of proper controls, efficient and effective audit systems, sound fraud risk management and putting in place an overall vision for the enterprise. Companies with effective corporate governance mechanisms are usually strong and fraud-resilient. It was also discovered that companies with big 4 audit firms tend to have better governance structures in Mongolia.

Keywords: accountants, corporate disclosure, corporate failure, corporate governance

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Authors: Sima Majnooni

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This paper discusses the Green Climate Fund's environmental and social management framework (GCF). The environmental and social management framework ensures the accredited entity considers the GCF's accreditation standards and effectively implements each of the GCF-funded projects. The GCF requires all accredited entities to meet basic transparency and accountability standards as well as environmental and social safeguards (ESMS). In doing so, the accredited entity sets up different independent units. One of these units is called the Grievance Mechanism. When allegations of environmental and social harms are raised in association with GCF-funded activities, affected parties can contact the entity’s grievance unit. One of the most challenging things about the accredited entity's grievance unit is the lack of available information and resources on the entities' websites. Many AEs have anti-corruption or anti-money laundering unit, but they do not have the environmental and social unit for affected people. This paper will argue the effectiveness of environmental and social grievance mechanisms of AEs by using a qualitative approach to indicate how many of AEs have a poor or an effective GRM. Some ESMSs seem highly effective. On the other hand, other mechanisms lack basic requirements such as a clear, transparent, uniform procedure and a definitive timetable. We have looked at each AE mechanism not only in light of how the website goes into detail regarding the process of grievance mechanism but also in light of their risk category. Many mechanisms appear inadequate for the lower level risk category entities (C) and, even surprisingly, for many higher-risk categories (A). We found; in most cases, the grievance mechanism of AEs seems vague.

Keywords: grievance mechanism, vague environmental and social policies, green climate fund, international climate finance, lower and higher risk category

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Authors: Jiwuer Jilili, Ulrich Eckern, Udo Schwingenschlogl

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We present first principles results for the electronic, magnetic, and optical properties of the BiFeO3 /La2/3Sr1/3MnO3 heterostructure as obtained by spin polarized calculations using density functional theory. The electronic states of the heterostructure are compared to those of the bulk compounds. Structural relaxation turns out to have only a minor impact on the chemical bonding, even though the oxygen octahedra in La2/3Sr1/3MnO3 develop some distortions due to the interface strain. While a small charge transfer affects the heterointerfaces, our results demonstrate that the half-metallic character of La2/3Sr1/3MnO3 is fully maintained.

Keywords: BiFeO3, La2/3Sr1/3MnO3, superlattice, half-metallicity

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Authors: Guenther Schuh, Michael Riesener, Jan Kantelberg

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Due to the fugacity of markets and the reduction of product lifecycles, manufacturing companies from high-wage countries are nowadays faced with the challenge to place more innovative products within even shorter development time on the market. At the same time, volatile customer requirements have to be satisfied in order to successfully differentiate from market competitors. One potential approach to address the explained challenges is provided by agile values and principles. These agile values and principles already proofed their success within software development projects in the form of management frameworks like Scrum or concrete procedure models such as Extreme Programming or Crystal Clear. Those models lead to significant improvements regarding quality, costs and development time and are therefore used within most software development projects. Motivated by the success within the software industry, manufacturing companies have tried to transfer agile mechanisms of action to the development of hardware products ever since. Though first empirical studies show similar effects in the agile development of hardware products, no comprehensive procedure model for the design of development iterations has been developed for hardware development yet due to different constraints of the domains. For this reason, this paper focusses on the design of agile product development processes by transferring mechanisms of action used in agile software development towards product development. This is conducted by decomposing the individual systems 'product development' and 'agile software development' into relevant elements and symbiotically composing the elements of both systems in respect of the design of agile product development processes afterwards. In a first step, existing product development processes are described following existing approaches of the system theory. By analyzing existing case studies from industrial companies as well as academic approaches, characteristic objectives, activities and artefacts are identified within a target-, action- and object-system. In partial model two, mechanisms of action are derived from existing procedure models of agile software development. These mechanisms of action are classified in a superior strategy level, in a system level comprising characteristic, domain-independent activities and their cause-effect relationships as well as in an activity-based element level. Within partial model three, the influence of the identified agile mechanism of action towards the characteristic system elements of product development processes is analyzed. For this reason, target-, action- and object-system of the product development are compared with the strategy-, system- and element-level of agile mechanism of action by using the graph theory. Furthermore, the necessity of existence of activities within iteration can be determined by defining activity-specific degrees of freedom. Based on this analysis, agile product development processes are designed in form of different types of iterations within a last step. By defining iteration-differentiating characteristics and their interdependencies, a logic for the configuration of activities, their form of execution as well as relevant artefacts for the specific iteration is developed. Furthermore, characteristic types of iteration for the agile product development are identified.

Keywords: activity-based process model, agile mechanisms of action, agile product development, degrees of freedom

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Authors: Ifeyinwa Victor-Uadiale, Georgina Pearson, Sophie Witter, D. Reidpath

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Introduction: Smoking, alcohol misuse, unhealthy diet, and physical inactivity are the primary drivers of noncommunicable diseases (NCD), including cardiovascular diseases, cancers, respiratory diseases, and diabetes, worldwide. Collectively, these diseases are the leading cause of all global deaths, most of which are premature, affecting people between 30 and 70 years. Empirical evidence suggests that these risk behaviors can be modified by community-based interventions (CBI). However, there is little insight into the mechanisms and contextual factors of successful community interventions that impact risk behaviours for chronic diseases. This study examined “Under what circumstances, for whom, and how, do community-based interventions modify smoking, alcohol use, unhealthy diet, and physical inactivity among adults”. Adopting the Capability (C), Opportunity (O), Motivation (M), Behavior (B) (COM-B) framework for behaviour change, it sought to: (1) identify the mechanisms through which CBIs could reduce tobacco use and alcohol consumption and increase physical activity and the consumption of healthy diets and (2) examine the contextual factors that trigger the impact of these mechanisms on these risk behaviours among adults. Methods: Pawson’s realist review method was used to examine the literature. Empirical evidence and theoretical understanding were combined to develop a realist program theory that explains how CBIs influence NCD risk behaviours. Documents published between 2002 and 2020 were systematically searched in five electronic databases (CINAHL, Cochrane Library, Medline, ProQuest Central, and PsycINFO). They were included if they reported on community-based interventions aimed at cardiovascular diseases, cancers, respiratory diseases, and diabetes in a global context; and had an outcome targeted at smoking, alcohol, physical activity, and diet. Findings: Twenty-nine scientific documents were retrieved and included in the review. Over half of them (n = 18; 62%) focused on three of the four risk behaviours investigated in this review. The review identified four mechanisms: capability, opportunity, motivation, and social support that are likely to change the dietary and physical activity behaviours in adults given certain contexts. There were weak explanations of how the identified mechanisms could likely change smoking and alcohol consumption habits. In addition, eight contextual factors that may affect how these mechanisms impact physical activity and dietary behaviours were identified: suitability to work and family obligations, risk status awareness, socioeconomic status, literacy level, perceived need, availability and access to resources, culture, and group format. Conclusion: The findings suggest that CBIs are likely to improve the physical activity and dietary habits of adults if the intervention function seeks to educate, incentivize, change the environment, and model the right behaviours. The review applies and advances theory, realist research, and the design and implementation of community-based interventions for NCD prevention.

Keywords: community-based interventions, noncommunicable disease, realist program theory, risk behaviors

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Authors: Antonio Sepúlveda, Camila Marques, Carlos Bolonha, Igor De Lazari, Henrique Rangel

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The judicial practice faces a tension between normative discretion and institutional capacities. There are clarity graduations of the statutory text that might induce different specialization levels of the judges. A major problem stemming from that tension is a greater discretion without a proportional specialization. The normative clarity, although its absence can be overcome through specialization, avoids problems related to disproportionate discretion and judicial dissonance. When judicial interpretation deals with the lack of legal clarity, a significant juridical insecurity frame is verified. Decisional uniformity mechanisms are created in order to surpass these problems. Brazil brings great examples, such as the súmulas, the enunciados, and the súmulas vinculantes. Despite of the resistance presented to the latter, mainly based on judges’ independence, even countries of the Common Law tradition develop such mechanisms. The British Guidelines face the lack of legal clarity problem and promote a decisional consonance system.

Keywords: generalist judges, institutional capacities, normative clarity, normative discretion

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