Search results for: eXtreme gradient boosting

Authors: Sundaresan Soundararajan, George Ezekiel Silvananthan, Chor Ngee Tan

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Introduction: Transforaminal Interbody Fusion (TLIF) has been adopted for many decades now, however, XLIF, still in relative infancy, has grown to be accepted as a new Minimally Invasive Surgery (MIS) option. There is a paucity of reports directly comparing lateral approach surgery to other MIS options such as TLIF in the treatment of lumbar degenerative disc diseases. Aims/Objectives: The objective of this study was to compare the efficacy and clinical outcomes between Minimally Invasive Transforaminal Interbody Fusion (TLIF) and Minimally Invasive Lateral Interbody Fusion (XLIF) in the treatment of patients with degenerative disc disease of the lumbar spine. Methods: A single center, retrospective cohort study involving a total of 38 patients undergoing surgical intervention between 2010 and 2013 for degenerative disc disease of lumbar spine at single L4/L5 level. 18 patients were treated with MIS TLIF, and 20 patients were treated with XLIF. Results: The XLIF group showed shorter duration of surgery compared to the TLIF group (176 mins vs. 208.3 mins, P = 0.03). Length of hospital stay was also significantly shorter in XLIF group (5.9 days vs. 9 days, p = 0.03). Intraoperative blood loss was favouring XLIF as 85% patients had blood loss less than 100cc compared to 58% in the TLIF group (P = 0.03). Radiologically, disc height was significantly improved post operatively in the XLIF group compared to the TLIF group (0.56mm vs. 0.39mm, P = 0.01). Foraminal height increment was also higher in the XLIF group (0.58mm vs. 0.45mm , P = 0.06). Clinically, back pain and leg pain improved in 85% of patients in the XLIF group and 78% in the TLIF group. Post op hip flexion weakness was more common in the XLIF group (40%) than in the TLIF group (0%). However, this weakness resolved within 6 months post operatively. There was one case of dural tear and surgical site infection in the TLIF group respectively and none in the XLIF group. Visual Analog Scale (VAS) score 6 months post operatively showed comparable reduction in both groups. TLIF group had Owsterty Disability Index (ODI) improvement on 67% while XLIF group showed improvement of 70% of its patients. Conclusions: Lateral approach surgery shows comparable clinical outcomes in resolution of back pain and radiculopathy to conventional MIS techniques such as TLIF. With significantly shorter duration of surgical time, minimal blood loss and shorter hospital stay, XLIF seems to be a reasonable MIS option compared to other MIS techniques in treating degenerative lumbar disc diseases.

Keywords: extreme lateral interbody fusion, lateral approach, minimally invasive, XLIF

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Authors: T. Al-Alawi, N. Shorbaji, E. Rashaidi, M.Alidrisi

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Purpose/Objective(s): The main purpose of this study is to analyze the planning of SBRT treatments for localized prostate cancer with 6FFF and 10FFF energies to see if there is a dosimetric difference between the two energies and how we can increase the plan efficiency and reduce its complexity. Also, to introduce a planning method in our department to treat prostate cancer by utilizing high energy photons without increasing patient toxicity and fulfilled all dosimetric constraints for OAR (an organ at risk). Then toevaluate the target 95% coverage PTV95, V5%, V2%, V1%, low dose volume for OAR (V1Gy, V2Gy, V5Gy), monitor unit (beam-on time), and estimate the values of homogeneity index HI, conformity index CI a Gradient index GI for each treatment plan.Materials/Methods: Two treatment plans were generated for15 patients with localized prostate cancer retrospectively using the CT planning image acquired for radiotherapy purposes. Each plan contains two/three complete arcs with two/three different collimator angle sets. The maximum dose rate available is 1400MU/min for the energy 6FFF and 2400MU/min for 10FFF. So in case, we need to avoid changing the gantry speed during the rotation, we tend to use the third arc in the plan with 6FFF to accommodate the high dose per fraction. The clinical target volume (CTV) consists of the entire prostate for organ-confined disease. The planning target volume (PTV) involves a margin of 5 mm. A 3-mm margin is favored posteriorly. Organs at risk identified and contoured include the rectum, bladder, penile bulb, femoral heads, and small bowel. The prescription dose is to deliver 35Gyin five fractions to the PTV and apply constraints for organ at risk (OAR) derived from those reported in references. Results: In terms of CI=0.99, HI=0.7, and GI= 4.1, it was observed that they are all thesame for both energies 6FFF and 10FFF with no differences, but the total delivered MUs are much less for the 10FFF plans (2907 for 6FFF vs.2468 for 10FFF) and the total delivery time is 124Sc for 6FFF vs. 61Sc for 10FFF beams. There were no dosimetric differences between 6FFF and 10FFF in terms of PTV coverage and mean doses; the mean doses for the bladder, rectum, femoral heads, penile bulb, and small bowel were collected, and they were in favor of the 10FFF. Also, we got lower V1Gy, V2Gy, and V5Gy doses for all OAR with 10FFF plans. Integral dosesID in (Gy. L) were recorded for all OAR, and they were lower with the 10FFF plans. Conclusion: High energy 10FFF has lower treatment time and lower delivered MUs; also, 10FFF showed lower integral and meant doses to organs at risk. In this study, we suggest usinga 10FFF beam for SBRTprostate treatment, which has the advantage of lowering the treatment time and that lead to lessplan complexity with respect to 6FFF beams.

Keywords: FFF beam, SBRT prostate, VMAT, prostate cancer

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Authors: Moien Mojabi, Aurelien Hospital, Daniel Potts, Chris Young, Albert Leung

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The wave analysis is an integral part of the hydrotechnical assessment carried out during the permitting and design phases for coastal structures, such as marinas. This analysis aims in quantifying: i) the Suitability of the coastal structure design against Small Craft Harbour wave tranquility safety criterion; ii) Potential environmental impacts of the structure (e.g., effect on wave, flow, and sediment transport); iii) Mooring and dock design and iv) Requirements set by regulatory agency’s (e.g., WSA section 11 application). While a complex three-dimensional hydrodynamic modelling approach can be applied on large-scale projects, the need for an efficient and reliable wave analysis method suitable for smaller scale marina projects was identified. As a result, Tetra Tech has developed and applied an integrated analysis framework (hereafter TT approach), which takes the advantage of the state-of-the-art numerical models while preserving the level of simplicity that fits smaller scale projects. The present paper aims to describe the TT approach and highlight the key advantages of using this integrated framework in lake marina projects. The core of this methodology is made by integrating wind, water level, bathymetry, and structure geometry data. To respond to the needs of specific projects, several add-on modules have been added to the core of the TT approach. The main advantages of this method over the simplified analytical approaches are i) Accounting for the proper physics of the lake through the modelling of the entire lake (capturing real lake geometry) instead of a simplified fetch approach; ii) Providing a more realistic representation of the waves by modelling random waves instead of monochromatic waves; iii) Modelling wave-structure interaction (e.g. wave transmission/reflection application for floating structures and piles amongst others); iv) Accounting for wave interaction with the lakebed (e.g. bottom friction, refraction, and breaking); v) Providing the inputs for flow and sediment transport assessment at the project site; vi) Taking in consideration historical and geographical variations of the wind field; and vii) Independence of the scale of the reservoir under study. Overall, in comparison with simplified analytical approaches, this integrated framework provides a more realistic and reliable estimation of wave parameters (and its spatial distribution) in lake marinas, leading to a realistic hydrotechnical assessment accessible to any project size, from the development of a new marina to marina expansion and pile replacement. Tetra Tech has successfully utilized this approach since many years in the Okanagan area.

Keywords: wave modelling, wind-wave, extreme value analysis, marina

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Authors: Zheng Wang, Zhenhong Li, Jon Mills

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Ground-based synthetic aperture radar (GBSAR) represents a powerful remote sensing tool for deformation monitoring towards various geohazards, e.g. landslides, mudflows, avalanches, infrastructure failures, and the subsidence of residential areas. Unlike spaceborne SAR with a fixed revisit period, GBSAR data can be acquired with an adjustable temporal resolution through either continuous or discontinuous operation. However, challenges arise from processing high temporal-resolution continuous GBSAR data, including the extreme cost of computational random-access-memory (RAM), the delay of displacement maps, and the loss of temporal evolution. Moreover, repositioning errors between discontinuous campaigns impede the accurate measurement of surface displacements. Therefore, a versatile package with two complete chains is developed in this study in order to process both continuous and discontinuous GBSAR data and address the aforementioned issues. The first chain is based on a small-baseline subset concept and it processes continuous GBSAR images unit by unit. Images within a window form a basic unit. By taking this strategy, the RAM requirement is reduced to only one unit of images and the chain can theoretically process an infinite number of images. The evolution of surface displacements can be detected as it keeps temporarily-coherent pixels which are present only in some certain units but not in the whole observation period. The chain supports real-time processing of the continuous data and the delay of creating displacement maps can be shortened without waiting for the entire dataset. The other chain aims to measure deformation between discontinuous campaigns. Temporal averaging is carried out on a stack of images in a single campaign in order to improve the signal-to-noise ratio of discontinuous data and minimise the loss of coherence. The temporal-averaged images are then processed by a particular interferometry procedure integrated with advanced interferometric SAR algorithms such as robust coherence estimation, non-local filtering, and selection of partially-coherent pixels. Experiments are conducted using both synthetic and real-world GBSAR data. Displacement time series at the level of a few sub-millimetres are achieved in several applications (e.g. a coastal cliff, a sand dune, a bridge, and a residential area), indicating the feasibility of the developed GBSAR data processing package for deformation monitoring of a wide range of scientific and practical applications.

Keywords: ground-based synthetic aperture radar, interferometry, small baseline subset algorithm, deformation monitoring

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Authors: Omar Romero-Hernandez, Federico Castillo, Armando Sanchez, Sergio Romero, Andrea Romero, Michael Mitchell

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Environmental policies for resource conservation in rural areas include subsidies on services and social programs to cover living expenses. Government's expectation is that rural communities who benefit from social programs, such as payment for ecosystem services, are provided with an incentive to conserve natural resources and preserve natural sinks for greenhouse gases. At the same time, global climate change has affected the lives of people worldwide. The capability to adapt to global warming depends on the available resources and the standard of living, putting rural communities at a disadvantage. This paper explores whether rural entrepreneurship can represent a solution to resource conservation and global warming adaptation in rural communities. The research focuses on a sample of two coffee communities in Oaxaca, Mexico. Researchers used geospatial information contained in aerial photographs of the geographical areas of interest. Households were identified in the photos via the roofs of households and georeferenced via coordinates. From the household population, a random selection of roofs was performed and received a visit. A total of 112 surveys were completed, including questions of socio-demographics, perception to climate change and adaptation activities. The population includes two groups of study: entrepreneurs and non-entrepreneurs. Data was sorted, filtered, and validated. Analysis includes descriptive statistics for exploratory purposes and a multi-regression analysis. Outcomes from the surveys indicate that coffee farmers, who demonstrate entrepreneurship skills and hire employees, are more eager to adapt to climate change despite the extreme adverse socioeconomic conditions of the region. We show that farmers with entrepreneurial tendencies are more creative in using innovative farm practices such as the planting of shade trees, the use of live fencing, instead of wires, and watershed protection techniques, among others. This result counters the notion that small farmers are at the mercy of climate change and have no possibility of being able to adapt to a changing climate. The study also points to roadblocks that farmers face when coping with climate change. Among those roadblocks are a lack of extension services, access to credit, and reliable internet, all of which reduces access to vital information needed in today’s constantly changing world. Results indicate that, under some circumstances, funding and supporting entrepreneurship programs may provide more benefit than traditional social programs.

Keywords: entrepreneurship, global warming, rural communities, climate change adaptation

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Authors: Maher Z. Mohammed, Barry G. Clarke

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As an alternative to stone column in fine grained soils, it is possible to create stiffened columns of soils using electroosmosis (electroosmotic piles). This program of this research is to establish the effectiveness and efficiency of the process in different soils. The aim of this study is to assess the capability of electroosmosis treatment in a range of composite soils. The combined electroosmotic and preloading equipment developed by Nizar and Clarke (2013) was used with an octagonal array of anodes surrounding a single cathode in a nominal 250mm diameter 300mm deep cylinder of soil and 80mm anode to cathode distance. Copper coiled springs were used as electrodes to allow the soil to consolidate either due to an external vertical applied load or electroosmosis. The equipment was modified to allow the temperature to be monitored during the test. Electroosmotic tests were performed on China Clay Grade E kaolin and calcium bentonite (Bentonex CB) mixed with sand fraction C (BS 1881 part 131) at different ratios by weight; (0, 23, 33, 50 and 67%) subjected to applied voltages (5, 10, 15 and 20). The soil slurry was prepared by mixing the dry soil with water to 1.5 times the liquid limit of the soil mixture. The mineralogical and geotechnical properties of the tested soils were measured before the electroosmosis treatment began. In the electroosmosis cell tests, the settlement, expelled water, variation of electrical current and applied voltage, and the generated heat was monitored during the test time for 24 osmotic tests. Water content was measured at the end of each test. The electroosmotic tests are divided into three phases. In Phase 1, 15 kPa was applied to simulate a working platform and produce a uniform soil which had been deposited as a slurry. 50 kPa was used in Phase 3 to simulate a surcharge load. The electroosmotic treatment was only performed during Phase 2 where a constant voltage was applied through the electrodes in addition to the 15 kPa pressure. This phase was stopped when no further water was expelled from the cell, indicating the electroosmotic process had stopped due to either the degradation of the anode or the flow due to the hydraulic gradient exactly balanced the electroosmotic flow resulting in no flow. Control tests for each soil mixture were carried out to assess the behaviour of the soil samples subjected to only an increase of vertical pressure, which is 15kPa in Phase 1 and 50kPa in Phase 3. Analysis of the experimental results from this study showed a significant dewatering effect on the soil slurries. The water discharged by the electroosmotic treatment process decreased as the sand content increased. Soil temperature increased significantly when electrical power was applied and drops when applied DC power turned off or when the electrode degraded. The highest increase in temperature was found in pure clays at higher applied voltage after about 8 hours of electroosmosis test.

Keywords: electrokinetic treatment, electrical conductivity, electroosmotic consolidation, electroosmosis permeability ratio

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Authors: Mia Bahar, Özlem Bozkurt

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Obsessive-compulsive disorder (OCD) is a typical, persistent, and long-lasting mental health condition in which a person experiences uncontrollable, recurrent thoughts (or "obsessions") and/or activities (or "compulsions") that they feel compelled to engage in repeatedly. Obsessive-compulsive disorder is both underdiagnosed and undertreated. It frequently manifests in a variety of medical settings and is persistent, expensive, and burdensome. Obsessive-compulsive neurosis was long believed to be a condition that offered valuable insight into the inner workings of the unconscious mind. Obsessive-compulsive disorder is now recognized as a prime example of a neuropsychiatric condition susceptible to particular pharmacotherapeutic and psychotherapy therapies and mediated by pathology in particular neural circuits. An obsessive-compulsive disorder which is called OCD, usually has two components, one cognitive and the other behavioral, although either can occur alone. Obsessions are often repetitive and intrusive thoughts that invade consciousness. These obsessions are incredibly hard to control or dismiss. People who have OCD often engage in rituals to reduce anxiety associated with intrusive thoughts. Once the ritual is formed, the person may feel extreme relief and be free from anxiety until the thoughts of contamination intrude once again. These thoughts are strengthened through a manifestation of negative reinforcement because they allow the person to avoid anxiety and obscurity. These thoughts are described as autogenous, meaning they most likely come from nowhere. These unwelcome thoughts are related to actions which we can describe as Thought Action Fusion. The thought becomes equated with an action, such as if they refuse to perform the ritual, something bad might happen, and so people perform the ritual to escape the intrusive thought. In almost all cases of OCD, the person's life gets extremely disturbed by compulsions and obsessions. Studies show OCD is an estimated 1.1% prevalence, making it a challenging issue with high co-morbidities with other issues like depressive episodes, panic disorders, and specific phobias. The first to reveal brain anomalies in OCD were numerous CT investigations, although the results were inconsistent. A few studies have focused on the orbitofrontal cortex (OFC), anterior cingulate gyrus (AC), and thalamus, structures also implicated in the pathophysiology of OCD by functional neuroimaging studies, but few have found consistent results. However, some studies have found abnormalities in the basal ganglion. There have also been some discussions that OCD might be genetic. OCD has been linked to families in studies of family aggregation, and findings from twin studies show that this relationship is somewhat influenced by genetic variables. Some Research has shown that OCD is a heritable, polygenic condition that can result from de novo harmful mutations as well as common and unusual variants. Numerous studies have also presented solid evidence in favor of a significant additive genetic component to OCD risk, with distinct OCD symptom dimensions showing both common and individual genetic risks.

Keywords: compulsions, obsessions, neuropsychiatric, genetic

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Authors: M. Szechynska-Hebda, M. Sobczak, E. Rozanska, J. Troczynska, Z. Banaszak, N. Hordyńska, M. Dyda, M. Wedzony

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Chloroplasts, as essential organelles for photosynthesis, play a critical role in plant development. However, disturbances in the proper functioning of chloroplasts, in the extreme case manifesting as albinism of tissues and whole plants, are a phenomenon often occurring in conditions deviating from natural (e.g., in vitro cultures applied in breeding programs). Using whole-transcriptome analysis (RNA-Seq) together with light, fluorescent and electron microscopy, it was shown, that development of chloroplasts and formation of green or albino plants in the androgenesis process are genotype-dependent; however, they could be modulated by sub-optimal temperature treatment. The reprogramming of the microspore development from gametophytic to sporophytic, and then regeneration of green plant can be positively regulated by cold stress (4 ⁰C). A high temperature stress (32 ⁰C) can induce androgenesis, but it is a factor negatively influencing green plant regeneration (promoting albinism). A similar effect on microspores, androgenesis, and subsequent chloroplast formation, is elicited as a result of postponing the date of spike collection from spring to summer in field conditions (natural temperature rise). It is determined in both environmental or genotypic manner. The delay of the sowing date (environmental effect) or growing of late genotypes (genotypic effect) result in spike maturation at higher temperatures and significantly enhance albino plant formation in androgenesis process. Such a temperature system (4 ⁰C vs. 32 ⁰C) was used to study the chloroplast biogenesis process in wheat and triticale. It was shown, that efficiency of physiological processes differentiates microspore development during cold reprograming in genotypes susceptible and resistant to androgenesis. Moreover, a great variation in developmental stages of the microspores in one anther is observed for susceptible genotypes. Microspores that are more physiologically active under cold conditions can activate signaling pathways and processes, which provide an appropriate supply of metabolites to cell compartments. This, in turn, fully correlates with the genotype-dependent efficiency of chloroplast formation (or different types of plastid) at particular steps of androgenesis. The effect obtained after applying a high temperature stress is different. High temperature causes a significant acceleration of microspore development and less variation in developmental stages at the end of the treatment. Therefore, the developmental diversity of the microspores in one anther seems to be a critical factor for subsequent cell and chloroplast differentiation. The work was financed by Ministry of Agriculture and Rural Development within Program: 'Biological Progress in Plant Production', project no HOR.hn.802.15.2018

Keywords: androgenesis, chloroplast biogenesis, temperature stress, wheat

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Authors: Virginia Venturini, Elisabet Walker, Aylen Carrasco-Millan

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Latin America stands at the front of climate change impacts, with forecasts projecting accelerated temperature and sea level rises compared to the global average. These changes are set to trigger a cascade of effects, including coastal retreat, intensified droughts in some nations, and heightened flood risks in others. In Argentina, wildfires historically affected forests, but since 2004, wetland fires have emerged as a pressing concern. By 2021, the wetlands of the Paraná River faced a dangerous situation. In fact, during the year 2021, a high-risk scenario was naturally formed in the wetlands of the Paraná River, in Argentina. Very low water levels in the rivers, and excessive standing dead plant material (fuel), triggered most of the fires recorded in the vast wetland region of the Paraná during 2020-2021. During 2008 fire events devastated nearly 15% of the Paraná Delta, and by late 2021 new fires burned more than 300,000 ha of these same wetlands. Therefore, the goal of this work is to explore remote sensing tools to monitor environmental conditions and the severity of prescribed burns in the Paraná River wetlands. Thus, two prescribed burning experiments were carried out in the study area (31°40’ 05’’ S, 60° 34’ 40’’ W) during September 2023. The first experiment was carried out on Sept. 13th, in a plot of 0.5 ha which dominant vegetation were Echinochloa sp., and Thalia, while the second trial was done on Sept 29th in a plot of 0.7 ha, next to the first burned parcel; here the dominant vegetation species were Echinochloa sp. and Solanum glaucophyllum. Field campaigns were conducted between September 8th and November 8th to assess the severity of the prescribed burns. Flight surveys were conducted utilizing a DJI® Inspire II drone equipped with a Sentera® NDVI camera. Then, burn severity was quantified by analyzing images captured by the Sentera camera along with data from the Sentinel 2 satellite mission. This involved subtracting the NDVI images obtained before and after the burn experiments. The results from both data sources demonstrate a highly heterogeneous impact of fire within the patch. Mean severity values obtained with drone NDVI images of the first experience were about 0.16 and 0.18 with Sentinel images. For the second experiment, mean values obtained with the drone were approximately 0.17 and 0.16 with Sentinel images. Thus, most of the pixels showed low fire severity and only a few pixels presented moderated burn severity, based on the wildfire scale. The undisturbed plots maintained consistent mean NDVI values throughout the experiments. Moreover, the severity assessment of each experiment revealed that the vegetation was not completely dry, despite experiencing extreme drought conditions.

Keywords: prescribed-burn, severity, NDVI, wetlands

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Authors: Saiyed M Ishtiaque, Priyal Dixit

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Objectives: An approach is being suggested to design the filter media to maximize the filtration efficiency with minimum possible pressure drop of composite nonwoven by incorporating the layers of different packing densities induced by fibre of different deniers and punching parameters by using the concept of sequential punching technique in specific order in layered composite nonwoven structure. X-ray computed tomography technique is used to measure the packing density along the thickness of layered nonwoven structure composed by placing the layer of differently oriented fibres influenced by fibres of different deniers and punching parameters in various combinations to minimize the pressure drop at maximum possible filtration efficiency. Methodology Used: This work involves preparation of needle punched layered structure with batts 100g/m2 basis weight having fibre denier, punch density and needle penetration depth as variables to produce 300 g/m2 basis weight nonwoven composite. X-ray computed tomography technique is used to measure the packing density along the thickness of layered nonwoven structure composed by placing the layers of differently oriented fibres influenced by considered variables in various combinations. to minimize the pressure drop at maximum possible filtration efficiencyFor developing layered nonwoven fabrics, batts made of fibre of different deniers having 100g/m2 each basis weight were placed in various combinations. For second set of experiment, the composite nonwoven fabrics were prepared by using 3 denier circular cross section polyester fibre having 64 mm length on needle punched nonwoven machine by using the sequential punching technique to prepare the composite nonwoven fabrics. In this technique, three semi punched fabrics of 100 g/m2 each having either different punch densities or needle penetration depths were prepared for first phase of fabric preparation. These fabrics were later punched altogether to obtain the overall basis weight of 300 g/m2. The total punch density of the composite nonwoven fabric was kept at 200 punches/ cm2 with a needle penetration depth of 10 mm. The layered structures so formed were subcategorised into two groups- homogeneous layered structure in which all the three batts comprising the nonwoven fabric were made from same denier of fibre, punch density and needle penetration depth and were placed in different positions in respective fabric and heterogeneous layered structure in which batts were made from fibres of different deniers, punch densities and needle penetration depths and were placed in different positions. Contributions: The results concluded that reduction in pressure drop is not derived by the overall packing density of the layered nonwoven fabric rather sequencing of layers of specific packing density in layered structure decides the pressure drop. Accordingly, creation of inverse gradient of packing density in layered structure provided maximum filtration efficiency with least pressure drop. This study paves the way for the possibility of customising the composite nonwoven fabrics by the incorporation of differently oriented fibres in constituent layers induced by considered variablres for desired filtration properties.

Keywords: filtration efficiency, layered nonwoven structure, packing density, pressure drop

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Authors: Xiaoling Ren, Guidong Yang

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Ammonia, as one of the largest-volume industrial chemicals, is mostly produced by century-old Haber-Bosch process with extreme conditionsand high-cost. Under the circumstance, researchersarededicated in finding new ways to replace the Haber-Bosch process. Photocatalytic nitrogen fixation is a promising sustainable, clear and green strategy for ammonia synthesis, butit is still a big challenge due to the high activation energy for nitrogen. It is essential to develop an efficient photocatalyst for making this approach industrial application. Constructing chemisorption active sites through defect engineering can be defined as an effective and reliable means to improve nitrogen activation by forming the extraordinary coordination environment and electronic structure. Besides, the construction of three-dimensionally orderdmacroporous (3DOM) structured photocatalyst is considered to be one of effectivestrategiesto improve the activity due to it canincrease the diffusion rate of reactants in the interior, which isbeneficial to the mass transfer process of nitrogen molecules in photocatalytic nitrogen reduction. Herein, Fe doped 3DOM WO₃(Fe-3DOM WO₃) without noble metal cocatalysts is synthesized by a polystyrene-template strategy, which is firstly used for photocatalytic nitrogen fixation. To elucidate the chemical nature of the dopant, the X-ray diffraction (XRD) analysiswas conducted. The pure 3DOM WO₃ has a monoclinic type crystal structure. And no additional peak is observed in Fe doped 3DOM WO₃, indicating that the incorporation of Fe atoms did not result in a secondary phase formation. In order to confirm the morphologies of Fe-3DOM WO₃and 3DOM WO₃, scanning electron microscopy (SEM) was employed. The synthesized Fe-3DOM WO₃and 3DOM WO₃ both exhibit a highly ordered three dimensional inverse opal structure with interconnected pores. From high-resolution TEM image of Fe-3DOM WO₃, the ordered lattice fringes with a spacing of 3.84 Å can be assigned to the (001) plane of WO₃, which is consistent with the XRD results. Finally, the photocatalytic nitrogen reduction performance of 3DOM WO₃ and Fe doped 3DOM WO₃with various Fe contents were examined. As a result, both Fe-3DOM WO₃ samples achieve higher ammonia production rate than that of pure 3DOM WO₃, indicating that the doped Fe plays a critical role in the photocatalytic nitrogen fixation performance. To verify the reaction process upon N2 reduction on the Fe-3DOM WO₃, in-situ diffuse reflectance infrared Fourier-transform spectroscopy was employed to monitor the intermediates. The in-situ DRIFTS spectra of Fe-3DOM WO₃ exhibit the increased signals with the irradiation time from 0–60min in the N2 atmosphere. The above results prove that nitrogen is gradually hydrogenated to produce ammonia over Fe-3DOM WO₃. Thiswork would enrich our knowledge in designing efficient photocatalystsfor photocatalytic nitrogen reduction.

Keywords: ammonia, photocatalytic, nitrogen fixation, Fe doped 3DOM WO₃

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Authors: Evelyn Bilias-Lolis, Emily Louise Winter

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Schools have a responsibility to implement school-wide frameworks that actively prevent, detect, and support all aspects of child development and learning. Such efforts can range from individual or classroom-level supports to school-wide primary prevention practices for the school’s infrastructure or climate. This study assessed the perceptions of educators across a variety of disciplines in Connecticut (i.e., elementary and secondary education, special education, school psychology, and school social work) on the perceived impact of their beliefs, language, and behavior about food and body consciousness on student self-image and school climate. Participants (N=50) completed a short electronic questionnaire measuring perceptions of how their behavior can influence their students’ opinions about themselves, their emerging self-image, and the overall climate of the school community. Secondly, the beliefs that were directly assessed in the first portion of the survey were further measured through the use of applied social vignettes involving students directly or as bystanders. Preliminary findings are intriguing. When asked directly, 100% of the respondents reported that what they say to students directly could influence student opinions about themselves and 98% of participants further agreed that their behavior both to and in front of students could impact a student’s developing self-image. Likewise, 82% of the sample agreed that their personal language and behavior affect the overall climate of a school building. However, when the above beliefs were assessed via applied social vignettes depicting routine social exchanges, results were significantly more widespread (i.e., results were evenly dispersed among levels of agreement and disagreement across participants in all areas). These preliminary findings offer humble but critical implications for informing integrated school wellness frameworks that aim to create body-sensitive school communities. Research indicates that perceptions about body image, attitudes about eating, and the onset of disordered eating practices surface in school-aged years. Schools provide a natural setting for instilling foundations for child wellness as a natural extension of existing school climate reform efforts. These measures do not always need to be expansive or extreme. Rather, educators have a ripe opportunity to become champions for health and wellness through increased self-awareness and subtle shifts in language and behavior. Future psychological research needs to continue to explore this line of inquiry using larger and more varied samples of educators in order to identify needs in teacher training and development that can yield positive and preventative health outcomes for children.

Keywords: body-sensitive schools, integrated school health, school climate reform, teacher awareness

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Authors: Alexandru-Ion Marinescu

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There exist a plethora of methods in the scientific literature which tackle the well-established task of credit score evaluation. In its most abstract form, a credit scoring algorithm takes as input several credit applicant properties, such as age, marital status, employment status, loan duration, etc. and must output a binary response variable (i.e. “GOOD” or “BAD”) stating whether the client is susceptible to payment return delays. Data imbalance is a common occurrence among financial institution databases, with the majority being classified as “GOOD” clients (clients that respect the loan return calendar) alongside a small percentage of “BAD” clients. But it is the “BAD” clients we are interested in since accurately predicting their behavior is crucial in preventing unwanted loss for loan providers. We add to this whole context the constraint that the algorithm must yield an actual, tractable mathematical formula, which is friendlier towards financial analysts. To this end, we have turned to genetic algorithms and genetic programming, aiming to evolve actual mathematical expressions using specially tailored mutation and crossover operators. As far as data representation is concerned, we employ a very flexible mechanism – LINQ expression trees, readily available in the C# programming language, enabling us to construct executable pieces of code at runtime. As the title implies, they model trees, with intermediate nodes being operators (addition, subtraction, multiplication, division) or mathematical functions (sin, cos, abs, round, etc.) and leaf nodes storing either constants or variables. There is a one-to-one correspondence between the client properties and the formula variables. The mutation and crossover operators work on a flattened version of the tree, obtained via a pre-order traversal. A consequence of our chosen technique is that we can identify and discard client properties which do not take part in the final score evaluation, effectively acting as a dimensionality reduction scheme. We compare ourselves with state of the art approaches, such as support vector machines, Bayesian networks, and extreme learning machines, to name a few. The data sets we benchmark against amount to a total of 8, of which we mention the well-known Australian credit and German credit data sets, and the performance indicators are the following: percentage correctly classified, area under curve, partial Gini index, H-measure, Brier score and Kolmogorov-Smirnov statistic, respectively. Finally, we obtain encouraging results, which, although placing us in the lower half of the hierarchy, drive us to further refine the algorithm.

Keywords: expression trees, financial credit scoring, genetic algorithm, genetic programming, symbolic evolution

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Authors: Efe Mary Isike

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The variety of relationships between migrants and host communities is an enduring theme of migration studies. On one extreme, there are numerous examples of hostility towards ‘strangers’ who are either ejected from society or denied access to jobs, housing, education, healthcare and other aspects of normal life. More moderate treatments of those identified as different include expectations of assimilation in which host communities expect socially marginalized groups to conform to norms that they define. Both exclusion and assimilation attempt to manage the problem of difference by removing it. South Africa experienced great influx of African immigrants who worked in mines and farms under harsh and exploitative conditions before and after the institutionalization of apartheid. Although these labour migrants contributed a great deal to the economic development of South Africa, they were not given citizenship status. The formal democratization in 1994 came with dreams and expectations of a more inclusive South Africa, where black South Africans hoped to maximize their potential in a more free, fair and equal society. In the same vein, it also opened spaces for an influx of especially African immigrants into the country which set the stage for a new form of contest for belonging between South African citizens and African migrant settlers. One major manifestation of this contest was the violent xenophobic attacks against African immigrants which predate that of May 2008 and has continued with lower intensity across the country since then. While it is doubtless possible to find abundant evidence of antagonism in the relations between South Africans and African immigrants, the purpose of this study is to investigate the everyday realities of migrants in ordinary places who interact with a variety of people through their livelihood activities, marriages and social relationships, moving around towns and cities, in their residential areas, in faith-based organizations and other elements of everyday life. Rather than assuming all relations are hostile, this study intends to look at the breadth of everyday relationships within a specific context. Based on the foregoing, the main task of this study is to holistically examine and explain the nature of interactions between African migrants and South African citizens by analysing the social network ties that connect them in the specific case of Umhlathuze municipality. It will also investigate the variety of networks that exists between African migrants and South Africans and examine the nature of the linkages in the various networks identified between these two groups in Umhlathuze Municipality. Apart from a review of relevant literature, policies and other official documents, this paper will employ a purposive sample survey and in-depth interview of African immigrants and South Africans within their networks in selected suburbs in KwaZulu-Natal.

Keywords: migration, networks, development, host communities

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Authors: Maha Atout, Pippa Hemingway, Jane Seymour

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A preliminary systematic review shows that health professionals experience a tension when communicating with the parents and family members of children with life-threatening and life-limiting conditions. On the one hand, they want to promote open and honest communication, while on the other, they are apprehensive about fostering an unrealistic sense of hope. Defining the boundaries between information that might offer reasonable hope versus that which results in false reassurance is challenging. Some healthcare providers worry that instilling a false sense of hope could motivate parents to seek continued aggressive treatment for their child, which in turn might cause the patient further unnecessary suffering. To date, there has been a lack of research in the Middle East regarding how healthcare providers do or should communicate bad news; in particular, the issue of hope in the field of paediatric palliative care has not been researched thoroughly. This study aims to explore, from the perspective of patients’ mothers, physicians, and nurses, the experience of communicating and receiving bad news in the care of children with palliative care needs. Data were collected using a collective qualitative case study approach across three paediatric units in a Jordanian hospital. Two data collection methods were employed: participant observation and semi-structured interviews. The overall number of cases was 15, with a total of 56 interviews with mothers (n=24), physicians (n=12), and nurses (n=20) completed, as well as 197 observational hours logged. The findings demonstrate that mothers wanted their doctors to provide them with hopeful information about the future progression of their child’s illness. Although some mothers asked their doctors to provide them with honest information regarding the condition of their child, they still considered a sense of hope to be essential for coping with caring for their child. According to mothers, hope was critical to treatment as it helped them to stay committed to the treatment and protected them to some extent from the extreme emotional suffering that would occur if they lost hope. The health professionals agreed with the mothers on the importance of hope, so long as it was congruent with the stage and severity of each patient’s disease. The findings of this study conclude that while parents typically insist on knowing all relevant information when their child is diagnosed with a severe illness, they considered hope to be an essential part of life, and they found it very difficult to handle suffering without any glimmer of it. This study finds that using negative terms has extremely adverse effects on the parents’ emotions. Hence, although the mothers asked the doctors to be as honest as they could, they still wanted the physicians to provide them with a positive message by communicating this information in a sensitive manner including hope.

Keywords: health professionals, children, communication, hope, information, mothers, palliative care

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Authors: G. Yanay-Ventura, H. Desivilya Syna, K. Michael

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Social businesses are based on the idea that an enterprise can be established for the sake of profit and, at the same time, with the aim of fulfilling social goals. Yet, the question of how these goals can be integrated in practice to derive parallel benefit in both realms still needs to be examined. Particularly notable in this context is the ‘governance challenge’ of social businesses, meaning the danger of the mission drifts from the social goal in the pursuit of good business. This study is based on an evaluation study of a social business that operates as a restaurant providing professional training to at-risk youth. The evaluation was based on the collection of a variety of data through interviews with stakeholders in the enterprise (directors and managers, business partners, social partners, and position holders in the restaurant and the social enterprise), a focus group consisting of the youth receiving the professional training, observations of the restaurant’s operation, and analysis of the social enterprise’s primary documents. The evaluation highlighted significant strengths of the social enterprise, including reaching relatively fast business sustainability, effective management of the restaurant, stable employment of the restaurant staff, and effective management of the social project. The social enterprise and business management have both enjoyed positive evaluations from a variety of stakeholders. Clearly, the restaurant was deemed by all a promising young business. However, the social project suffered from a 90% dropout rate among the youth entering its ranks, extreme monthly fluctuation in the number of youths participating, and a distinct minority of the youth who have succeeded in completing their training period. Possible explanations of the high dropout rate included the small number of cooks, which impeded the effectiveness of the training process and the provision of advanced cooking skills; lack of clarity regarding the essence and the elements of training; and lack of a meaningful peer group for the youth engaged in the program. Paradoxically, despite the stakeholders’ great appreciation for the social enterprise, the challenge of governability was also formidable, revealing a tangible risk of mission drift in the reduction of the social enterprise’s target population and a breach of the commitment made to the youth with regard to practical training. The risk of mission drifts emerged as a hidden and evasive issue for the stakeholders, who revealed a deep appreciation for the management and the outcomes of the social enterprise. The challenge of integration, therefore, requires an in-depth examination of how to maintain a successful business without hindering the achievement of the social goal. The study concludes that clear conceptualization of the training process and its aims, increased cooks’ participation in the social project, and novel conceptions with regard to the evaluation of success could serve to benefit the youth and impede mission drift.

Keywords: evaluation study, management, mission drift, social business

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Authors: Shaurya Chauhan, Sagar Gupta

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Prominent urbanizing centres across the globe like Delhi, Dhaka, or Manila have exhibited that development often faces a challenge in bridging the gap among the top-down collective requirements of the city and the bottom-up individual aspirations of the ever-diversifying population. When this exclusion is intertwined with rapid urbanization and diversifying urban demography: unplanned sprawl, poor planning, and low-density development emerge as automated responses. In parallel, new ideas and methods of densification and public participation are being widely adopted as sustainable alternatives for the future of urban development. This research advocates a collaborative design method for future development: one that allows rapid application with its prototypical nature and an inclusive approach with mediation between the 'user' and the 'urban', purely with the use of empirical tools. Building upon the concepts and principles of 'open-sourcing' in design, the research establishes a design framework that serves the current user requirements while allowing for future citizen-driven modifications. This is synthesized as a 3-tiered model: user needs – design ideology – adaptive details. The research culminates into a context-responsive 'open source project development framework' (hereinafter, referred to as OSPDF) that can be used for on-ground field applications. To bring forward specifics, the research looks at a 300-acre redevelopment in the core of a rapidly urbanizing city as a case encompassing extreme physical, demographic, and economic diversity. The suggestive measures also integrate the region’s cultural identity and social character with the diverse citizen aspirations, using architecture and urban design tools, and references from recognized literature. This framework, based on a vision – feedback – execution loop, is used for hypothetical development at the five prevalent scales in design: master planning, urban design, architecture, tectonics, and modularity, in a chronological manner. At each of these scales, the possible approaches and avenues for open- sourcing are identified and validated, through hit-and-trial, and subsequently recorded. The research attempts to re-calibrate the architectural design process and make it more responsive and people-centric. Analytical tools such as Space, Event, and Movement by Bernard Tschumi and Five-Point Mental Map by Kevin Lynch, among others, are deep rooted in the research process. Over the five-part OSPDF, a two-part subsidiary process is also suggested after each cycle of application, for a continued appraisal and refinement of the framework and urban fabric with time. The research is an exploration – of the possibilities for an architect – to adopt the new role of a 'mediator' in development of the contemporary urbanity.

Keywords: open source, public participation, urbanization, urban development

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Authors: Samuele Viaro, Pierre Ricco

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Görtler instabilities generate in boundary layers from an unbalance between pressure and centrifugal forces caused by concave surfaces. Their spatial streamwise evolution influences transition to turbulence. It is therefore important to understand even the early stages where perturbations, still small, grow linearly and could be controlled more easily. This work presents a rigorous theoretical framework for compressible flows using the linearized unsteady boundary region equations, where only the streamwise pressure gradient and streamwise diffusion terms are neglected from the full governing equations of fluid motion. Boundary and initial conditions are imposed through an asymptotic analysis in order to account for the interaction of the boundary layer with free-stream turbulence. The resulting parabolic system is discretize with a second-order finite difference scheme. Realistic flow parameters are chosen from wind tunnel studies performed at supersonic and subsonic conditions. The Mach number ranges from 0.5 to 8, with two different radii of curvature, 5 m and 10 m, frequencies up to 2000 Hz, and vortex spanwise wavelengths from 5 mm to 20 mm. The evolution of the perturbation flow is shown through velocity, temperature, pressure profiles relatively close to the leading edge, where non-linear effects can still be neglected, and growth rate. Results show that a global stabilizing effect exists with the increase of Mach number, frequency, spanwise wavenumber and radius of curvature. In particular, at high Mach numbers curvature effects are less pronounced and thermal streaks become stronger than velocity streaks. This increase of temperature perturbations saturates at approximately Mach 4 flows, and is limited in the early stage of growth, near the leading edge. In general, Görtler vortices evolve closer to the surface with respect to a flat plate scenario but their location shifts toward the edge of the boundary layer as the Mach number increases. In fact, a jet-like behavior appears for steady vortices having small spanwise wavelengths (less than 10 mm) at Mach 8, creating a region of unperturbed flow close to the wall. A similar response is also found at the highest frequency considered for a Mach 3 flow. Larger vortices are found to have a higher growth rate but are less influenced by the Mach number. An eigenvalue approach is also employed to study the amplification of the perturbations sufficiently downstream from the leading edge. These eigenvalue results are compared with the ones obtained through the initial value approach with inhomogeneous free-stream boundary conditions. All of the parameters here studied have a significant influence on the evolution of the instabilities for the Görtler problem which is indeed highly dependent on initial conditions.

Keywords: compressible boundary layers, Görtler instabilities, receptivity, turbulence transition

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Authors: Katarzyna Drela, Miroslaw Wielgos, Mikolaj Wrobel, Barbara Lukomska

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Mesenchymal stem cells (MSCs) have a great potential in regenerative medicine. Since the initial number of isolated MSCs is limited, in vitro propagation is often required to reach sufficient numbers of cells for therapeutic applications. During long-term culture MSCs may undergo genetic or epigenetic alterations that subsequently increase the probability of spontaneous malignant transformation. Thus, factors that influence genomic stability of MSCs following long-term expansions need to be clarified before cultured MSCs are employed for clinical application. The aim of our study was to investigate the potential for spontaneous transformation of human neonatal cord blood (HUCB-MSCs) and adult bone marrow (BM-MSCs) derived MSCs. Materials and Methods: HUCB-MSCs and BM-MSCs were isolated by standard Ficoll gradient centrifugations method. Isolated cells were initially plated in high density 106 cells per cm2. After 48 h medium were changed and non-adherent cells were removed. The malignant transformation of MSCs in vitro was evaluated by morphological changes, proliferation rate, ability to enter cell senescence, the telomerase expression and chromosomal abnormality. Proliferation of MSCs was analyzed with WST-1 reduction method and population doubling time (PDT) was calculated at different culture stages. Then the expression pattern of genes characteristic for mesenchymal or epithelial cells, as well as transcriptions factors were examined by RT-PCR. Concomitantly, immunocytochemical analysis of gene-related proteins was employed. Results: Our studies showed that MSCs from all bone marrow isolations ultimately entered senescence and did not undergo spontaneous malignant transformation. However, HUCB-MSCs from one of the 15 donors displayed an increased proliferation rate, failed to enter senescence, and exhibited an altered cell morphology. In this sample we observed two different cell phenotypes: one mesenchymal-like exhibited spindle shaped morphology and express specific mesenchymal surface markers (CD73, CD90, CD105, CD166) with low proliferation rate, and the second one with round, densely package epithelial-like cells with significantly increased proliferation rate. The PDT of epithelial-like populations was around 1day and 100% of cells were positive for proliferation marker Ki-67. Moreover, HUCB-MSCs showed a positive expression of human telomerase reverse transcriptase (hTERT), cMYC and exhibit increased number of CFU during the long-term culture in vitro. Furthermore, karyotype analysis revealed chromosomal abnormalities including duplications. Conclusions: Our studies demonstrate that HUCB-MSCs are susceptible to spontaneous malignant transformation during long-term culture. Spontaneous malignant transformation process following in vitro culture has enormous effect on the biosafety issues of future cell-based therapies and regenerative medicine regimens.

Keywords: mesenchymal stem cells, spontaneous, transformation, long-term culture

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Authors: Rafał Szmajser, Katarzyna Świetla, Mariusz Andrzejewski

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Robotic process automation (RPA) is a technology of repeatable business processes performed using computer programs, robots that simulate the work of a human being. This approach assumes replacing an existing employee with the use of dedicated software (software robots) to support activities, primarily repeated and uncomplicated, characterized by a low number of exceptions. RPA application is widespread in modern business services, particularly in the areas of Finance, Accounting and Human Resources Management. By utilizing this technology, the effectiveness of operations increases while reducing workload, minimizing possible errors in the process, and as a result, bringing measurable decrease in the cost of providing services. Regardless of how the use of modern information technology is assessed, there are also some doubts as to whether we should replace human activities in the implementation of the automation in business processes. After the initial awe for the new technological concept, a reflection arises: to what extent does the implementation of RPA increase the efficiency of operations or is there a Business Case for implementing it? If the business case is beneficial, in which business processes is the greatest potential for RPA? A closer look at these issues was provided by in this research during which the respondents’ view of the perceived advantages resulting from the use of robotization and automation in financial and accounting processes was verified. As a result of an online survey addressed to over 500 respondents from international companies, 162 complete answers were returned from the most important types of organizations in the modern business services industry, i.e. Business or IT Process Outsourcing (BPO/ITO), Shared Service Centers (SSC), Consulting/Advisory and their customers. Answers were provided by representatives of the positions in their organizations: Members of the Board, Directors, Managers and Experts/Specialists. The structure of the survey allowed the respondents to supplement the survey with additional comments and observations. The results formed the basis for the creation of a business case calculating tangible benefits associated with the implementation of automation in the selected financial processes. The results of the statistical analyses carried out with regard to revenue growth confirmed the correctness of the hypothesis that there is a correlation between job position and the perception of the impact of RPA implementation on individual benefits. Second hypothesis (H2) that: There is a relationship between the kind of company in the business services industry and the reception of the impact of RPA on individual benefits was thus not confirmed. Based results of survey authors performed simulation of business case for implementation of RPA in selected Finance and Accounting Processes. Calculated payback period was diametrically different ranging from 2 months for the Account Payables process with 75% savings and in the extreme case for the process Taxes implementation and maintenance costs exceed the savings resulting from the use of the robot.

Keywords: automation, outsourcing, business process automation, process automation, robotic process automation, RPA, RPA business case, RPA benefits

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Authors: João Pedro Zanella, Michel J. O. Fagundes

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Introduction: Drug use has been practised by humans universally for millennia, not excluding any population from these habits, however, the rampant drug use is a global concern due to the harm that affects the health of the world population. In this sense, it is observed the reduction of lasting and effective public policies for the resolution, increasing the demand for treatment services. With this comes ibogaine, an alkaloid derived from the root of an African bush (Tabernanthe Iboga), found mostly in Gabon and used widely by the native Bwiti population in rituals, and also other social groups, which demonstrates efficacy against chemical dependence, psychic and emotional disorders, opioid withdrawal was first confirmed by a study in rats done by Michailo Dzoljic and associates in 1988 and again in 1994. Methods: A brief description of the plant, its neurohumoral potential and the effects caused by ingested doses, in a simplified and objective way, will be discussed in the course of this abstract. Results: Ibogaine is not registered or passed by Anvisa, regarding safety and efficacy, and cannot be sold in Brazil. Its illegal trade reaches R$ 5 thousand for a session with the proceeds of the root, and its effect can last up to 72 hours, attributing Iboga's psychoactive effects to the alkaloid called ibogaine. The shrub where Ibogaine is located has pink and yellow flowers, and its fruit produced does not have psychoactive substances, but its root bark contains 6 to 7% indolic alkaloids. Besides extraction from the iboga plant, ibogaine hydrochloride can be semisynthesized from voacangine, another plant alkaloid that acts as a precursor. Its potential has the ability to perform multiple interactions with the neurotransmitter system, which are closely associated with addiction, including nicotinic, opioid and serotoninergic systems. Studies carried out by Edwards found that the doses administered of Iboga should be determined by a health professional when its purpose is to treat individuals for dependence on other drugs. Its use in small doses may cause an increase in sensibility, impaired vision and motor alterations; in moderate quantities, hallucinations, motor and neurological alterations and impaired vision; in high quantities it may cause hallucinations with personal events at a deeper level lasting up to 24 hours or more, followed by motor and visual alterations. Conclusion: The product extracted from the Iboga plant is of great importance in controlling addiction, reducing the need for the use of narcotics by patients, thus gaining a space of extreme importance in the treatment of users of psychoactive substances. It is remarkable the progress of the latest’s research about the usefulness of Ibogaine, and its benefits for certain treatments, even with the restriction of its sale in Brazil. Besides this, Ibogaine has an additional benefit of helping the patient to gain self-control over their destructive behaviours.

Keywords: alkaloids, dependence, Gabon, ibogaine

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Authors: Salwa Mohamed Salah Eldin, Howida Kamal Ibrahim

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Introduction: Major depressive disorder affects high proportion of the world’s population presenting cost load in health care. Extended release venlafaxine is more convenient and could reduce discontinuation syndrome. The once daily dosing also reduces the potential for adverse events such as nausea due to reduced Cmax. Venlafaxine is an effective first-line agent in the treatment of depression. A once daily formulation was designed to enhance patient compliance. Complexing with a resin was suggested to improve loading of the water soluble drug. The formulated systems were thoroughly evaluated in vitro to prove superiority to previous trials and were compared to the commercial extended release product in experimental animals. Materials and Methods: Venlafaxine-resinates were prepared using Dowex®50WX4-400 and Dowex®50WX8-100 at drug to resin weight ratio of 1: 1. The prepared resinates were evaluated for their drug content, particle shape and surface properties and in vitro release profile in gradient pH. The release kinetics and mechanism were evaluated. Venlafaxine-Dowex® resinates were encapsulated using O/W solvent evaporation technique. Poly-ε-caprolactone, Poly(D, L-lactide-co-glycolide) ester, Poly(D, L-lactide) ester and Eudragit®RS100 were used as coating polymers alone and in combination. Drug-resinate microcapsules were evaluated for morphology, entrapment efficiency and in-vitro release profile. The selected formula was tested in rabbits using a randomized, single-dose, 2-way crossover study against Effexor-XR tablets under fasting condition. Results and Discussion: The equilibrium time was 30 min for Dowex®50WX4-400 and 90 min for Dowex®50WX8-100. The percentage drug loaded was 93.96 and 83.56% for both resins, respectively. Both drug-Dowex® resintes were efficient in sustaining venlafaxine release in comparison to the free drug (up to 8h.). Dowex®50WX4-400 based venlafaxine-resinate was selected for further encapsulation to optimize the release profile for once daily dosing and to lower the burst effect. The selected formula (coated with a mixture of Eudragit RS and PLGA in a ratio of 50/50) was chosen by applying a group of mathematical equations according to targeted values. It recorded the minimum burst effect, the maximum MDT (Mean dissolution time) and a Q24h (percentage drug released after 24 hours) between 95 and 100%. The 90% confidence intervals for the test/reference mean ratio of the log-transformed data of AUC0–24 and AUC0−∞ are within (0.8–1.25), which satisfies the bioequivalence criteria. Conclusion: The optimized formula could be a promising extended release form of the water soluble, short half lived venlafaxine. Being a multiple unit formulation, it lowers the probability of dose dumping and reduces the inter-subject variability in absorption.

Keywords: biodegradable polymers, cation-exchange resin, microencapsulation, venlafaxine hcl

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Authors: Anjali Singh, Ashwani Raju, Vandana Devi, Mohmad Mohsin Atique, Satyendra Singh, Munendra Singh

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India is the biggest consumer of mercury and, consequently, a major emitter too. The increasing mercury contamination in India’s water resources has gained widespread attention and, therefore, atmospheric deposition is of critical concern. However, little emphasis was placed on the role of precipitation in the aquatic mercury cycle of the Ganga Alluvial Plain which provides drinking water to nearly 7% of the world’s human population. A majority of the precipitation here occurs primarily in 10% duration of the year in the monsoon season. To evaluate the sources and transportation of mercury, water sample analysis has been conducted from two selected sites near Lucknow, which have a strong hydraulic gradient towards the river. 31 groundwater samples from Jehta village (26°55’15’’N; 80°50’21’’E; 119 m above mean sea level) and 31 river water samples from the Behta Nadi (a tributary of the Gomati River draining into the Ganga River) were collected during the monsoon season on every alternate day between 01 July to 30 August 2019. The total mercury analysis was performed by using Flow Injection Atomic Absorption Spectroscopy (AAS)-Mercury Hybride System, and daily rainfall data was collected from the India Meteorological Department, Amausi, Lucknow. The ambient groundwater and river-water concentrations were both 2-4 ng/L as there is no known geogenic source of mercury found in the area. Before the onset of the monsoon season, the groundwater and the river-water recorded mercury concentrations two orders of magnitude higher than the ambient concentrations, indicating the regional transportation of the mercury from the non-point source into the aquatic environment. Maximum mercury concentrations in groundwater and river-water were three orders of magnitude higher than the ambient concentrations after the onset of the monsoon season characterizing the considerable mobilization and redistribution of mercury by monsoonal precipitation. About 50% of both of the water samples were reported mercury below the detection limit, which can be mostly linked to the low intensity of precipitation in August and also with the dilution factor by precipitation. The highest concentration ( > 1200 ng/L) of mercury in groundwater was reported after 6-days lag from the first precipitation peak. Two high concentration peaks (>1000 ng/L) in river-water were separately correlated with the surface flow and groundwater outflow of mercury. We attribute the elevated mercury concentration in both of the water samples before the precipitation event to mercury originating from the extensive use of agrochemicals in mango farming in the plain. However, the elevated mercury concentration during the onset of monsoon appears to increase in area wetted with atmospherically deposited mercury, which migrated down from surface water to groundwater as downslope migration is a fundamental mechanism seen in rivers of the alluvial plain. The present study underscores the significance of monsoonal precipitation in the transportation of mercury to drinking water resources of the Ganga Alluvial Plain. This study also suggests that future research must be pursued for a better understand of the human health impact of mercury contamination and for quantification of the role of Ganga Alluvial Plain in the Global Mercury Cycle.

Keywords: drinking water resources, Ganga alluvial plain, india, mercury

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Authors: Justine Kiiza, Xu Jiafang

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The world’s demand for energy is increasing rapidly due to population growth and a reduction in shallow conventional oil and gas reservoirs, resorting to deeper and mostly unconventional reserves like shale oil and gas. Most shale formations contain a large amount of expansive sodium montmorillonite (Na-Mnt), due to high water adsorption, hydration, and when the drilling fluid filtrate enters the formation with high Mnt content, the wellbore wall can be unstable due to hydration and swelling, resulting to shrinkage, sticking, balling, time wasting etc., and well collapse in extreme cases causing complex downhole accidents and high well costs. Recently, polyamines like 1, 6 – hexane diamine (HEDA) have been used as typical drilling fluid shale inhibitors to minimize and/or cab clay mineral swelling and maintain the wellbore stability. However, their application is limited to shallow drilling due to their sensitivity to elevated temperature and pressure. Inorganic potassium salts i.e., KCl, have long been applied for restriction of shale formation hydration expansion in deep wells, but their use is limited due to toxicity. Understanding the adsorption behaviour of HEDA on Na-Mnt surfaces in present of organo-salts, organic K-salts e.g., HCO₂K - main component of organo-salt drilling fluid, is of great significance in explaining the inhibitory performance of polyamine inhibitors. Molecular dynamic simulations (MD) were applied to investigate the influence of HCO₂K and KCl on the adsorption mechanism of HEDA on the Na-Mnt surface. Simulation results showed that adsorption configurations of HEDA are mainly by terminal amine groups with a flat-lying alkyl hydrophobic chain. Its interaction with the clay surface decreased the H-bond number between H₂O-clay and neutralized the negative charge of the Mnt surface, thus weakening the surface hydration ability of Na-Mnt. The introduction of HCO₂K greatly improved inhibition ability, coordination of interlayer ions with H₂O as they were replaced by K+, and H₂O-HCOO- coordination reduced H₂O-Mnt interactions, mobility and transport capability of H₂O molecules were more decreased. While KCl showed little ability and also caused more hydration with time, HCO₂K can be used as an alternative for offshore drilling instead of toxic KCl, with a maximum concentration noted in this study as 1.65 wt%. This study provides a theoretical elucidation for the inhibition mechanism and adsorption characteristics of HEDA inhibitor on Na-Mnt surfaces in the presence of K+-salts and may provide more insight into the evaluation, selection, and molecular design of new clay-swelling high-performance WBDF systems used in oil and gas complex offshore drilling well sections.

Keywords: shale, hydration, inhibition, polyamines, organo-salts, simulation

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Authors: Loveline Ambo Angwah

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The processing of cassava from tubers or roots into food using crude and rudimentary method (hand peeling, grating, frying and to sun drying) is a very cumbersome and difficult process. The crude methods are time consuming and labour intensive. While on the other hand, modern processing method, that is using machines to perform the various processes as washing, peeling, grinding, oven drying, fermentation and frying is easier, less time consuming, and less labour intensive. Rudimentarily, cassava roots are processed into numerous products and utilized in various ways according to local customs and preferences. For the people of Ngwo village, cassava is transformed locally into flour or powder form called ‘cumcum’. It is also sucked into water to give a kind of food call ‘water fufu’ and fried to give ‘garri’. The leaves are consumed as vegetables. Added to these, its relative high yields; ability to stay underground after maturity for long periods give cassava considerable advantage as a commodity that is being used by poor rural folks in the community, to fight poverty. It plays a major role in efforts to alleviate the food crisis because of its efficient production of food energy, year-round availability, tolerance to extreme stress conditions, and suitability to present farming and food systems in Africa. Improvement of cassava processing and utilization techniques would greatly increase labor efficiency, incomes, and living standards of cassava farmers and the rural poor, as well as enhance the-shelf life of products, facilitate their transportation, increase marketing opportunities, and help improve human and livestock nutrition. This paper presents a general overview of crude ways in cassava processing and utilization methods now used by subsistence and small-scale farmers in Ngwo village of the North West region in Cameroon, and examine the opportunities of improving processing technologies. Cassava needs processing because the roots cannot be stored for long because they rot within 3-4 days of harvest. They are bulky with about 70% moisture content, and therefore transportation of the tubers to markets is difficult and expensive. The roots and leaves contain varying amounts of cyanide which is toxic to humans and animals, while the raw cassava roots and uncooked leaves are not palatable. Therefore, cassava must be processed into various forms in order to increase the shelf life of the products, facilitate transportation and marketing, reduce cyanide content and improve palatability.

Keywords: cassava roots, crude ways, food system, poverty

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Authors: Gema M. Rodado, Jose M. Olavarrieta

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Hydrogen fuel cell technologies have experienced a great boost in the last decades, significantly increasing the production of these devices for both stationary and portable (mainly automotive) applications; these are influenced by two main factors: environmental pollution and energy shortage. A fuel cell is an electrochemical device that converts chemical energy directly into electricity by using hydrogen and oxygen gases as reactive components and obtaining water and heat as byproducts of the chemical reaction. Fuel cells, specifically those of Proton Exchange Membrane (PEM) technology, are considered an alternative to internal combustion engines, mainly because of the low emissions they produce (almost zero), high efficiency and low operating temperatures (< 373 K). The introduction and use of fuel cells in the automotive market requires the development of standardized and validated procedures to test and evaluate their performance in different environmental conditions including vibrations and freeze-thaw cycles. These situations of vibration and extremely low/high temperatures can affect the physical integrity or even the excellent operation or performance of the fuel cell stack placed in a vehicle in circulation or in different climatic conditions. The main objective of this work is the development and validation of vibration and freeze-thaw cycling test procedures for fuel cell stacks that can be used in a vehicle in order to consolidate their safety, performance, and durability. In this context, different experimental tests were carried out at the facilities of the National Hydrogen Centre (CNH2). The experimental equipment used was: A vibration platform (shaker) for vibration test analysis on fuel cells in three axes directions with different vibration profiles. A walk-in climatic chamber to test the starting, operating, and stopping behavior of fuel cells under defined extreme conditions. A test station designed and developed by the CNH2 to test and characterize PEM fuel cell stacks up to 10 kWe. A 5 kWe PEM fuel cell stack in off-operation mode was used to carry out two independent experimental procedures. On the one hand, the fuel cell was subjected to a sinusoidal vibration test on the shaker in the three axes directions. It was defined by acceleration and amplitudes in the frequency range of 7 to 200 Hz for a total of three hours in each direction. On the other hand, the climatic chamber was used to simulate freeze-thaw cycles by defining a temperature range between +313 K and -243 K with an average relative humidity of 50% and a recommended ramp up and rump down of 1 K/min. The polarization curve and gas leakage rate were determined before and after the vibration and freeze-thaw tests at the fuel cell stack test station to evaluate the robustness of the stack. The results were very similar, which indicates that the tests did not affect the fuel cell stack structure and performance. The proposed procedures were verified and can be used as an initial point to perform other tests with different fuel cells.

Keywords: climatic chamber, freeze-thaw cycles, PEM fuel cell, shaker, vibration tests

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Authors: J. D. Temperman

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Introduction: In particular, in relation to religion, the meaning and scope of freedom of expression have been tested in recent times. This paper investigates the legal justifications for restrictions that have been suggested in this area and asks whether they are sustainable from an international human rights perspective. The universal human rights instruments, particularly the UN International Covenant on Civil and Political Rights (ICCPR), are increasingly geared towards eradicating ‘incitement’ to contingent harms like violence or discrimination, whilst forms of extreme speech that fall short of such incitement are to be protected rather than countered by states. Human Rights Committee’s draft-General Comment on freedom of expression, adopted in 2011, provides another strong indication that this is the envisaged way forward: repealing anti-blasphemy and anti-religious defamation laws, whilst simultaneously increasing efforts to combat ‘incitement’. Within regional human rights frameworks, notably the European Convention system, judgments have in fact supported legal restrictions on both hate speech, holocaust denial, and blasphemy or religious defamation. Major contributions to scholarship: This paper proposes an actus reus for the offense of ‘advocacy of religious hatred that constitutes incitement to discrimination or violence’, as enshrined in Article 20(2) of the UN ICCPR. In underscoring the high threshold of ‘incitement’, the author distinguishes this offense from such notions as ‘blasphemy’ or ‘defamation of religions’. In addition to treating the said provision as a sui generis prohibition, the question is addresses whether a ‘right to be protected against incitement’ may be distilled from the ICCPR. Furthermore, the author will discuss the question of how to judge incitement; notably, is mens rea required to convict someone of incitement, and if so, what degree of mens rea? This analysis also includes the question how to balance content and context factors when addressing alleged instances of incitement, notably what factors make provide for a likelihood that imminent acts of violence or discrimination will ensue from an inciteful speech act? Methodology: This paper takes a double comparative approach: (i) it endeavours to compare and contrast monitoring bodies’ approach to incitement (notably, the UN Human Rights Committee, but also the UN Committee on the Elimination of Racial Discrimination which monitors states’ compliance with Article 4 of ICERD on incitement); and (ii) it endeavours to chart and compare and analyse from an international human rights perspective recent forms of state practice in the field of dealing with incitement (i.e. a comparative legal analysis and vertical human rights analysis of newly emerging incitement legislation in the light of the said international standards). Conclusion: This paper conceptualizes a legal notion – ‘incitement’ – encapsulated in international human rights law that may have a profound bearing on contemporary challenges of radicalization and religious strife.

Keywords: incitement, international human rights law, religious hatred, violence

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Authors: Afsheen Aman, Zainab Bibi, Shah Ali Ul Qader

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Introduction: Xylan is a heteropolysaccharide composed of xylose monomers linked together through 1,4 linkages within a complex xylan network. Owing to wide applications of xylan hydrolytic products (xylose, xylobiose and xylooligosaccharide) the researchers are focusing towards the development of various strategies for efficient xylan degradation. One of the most important strategies focused is the use of heat tolerant biocatalysts which acts as strong and specific cleaving agents. Therefore, the exploration of microbial pool from extremely diversified ecosystem is considerably vital. Microbial populations from extreme habitats are keenly explored for the isolation of thermophilic entities. These thermozymes usually demonstrate fast hydrolytic rate, can produce high yields of product and are less prone to microbial contamination. Another possibility of degrading xylan continuously is the use of immobilization technique. The current work is an effort to merge both the positive aspects of thermozyme and immobilization technique. Methodology: Geobacillus stearothermophilus was isolated from soil sample collected near the blast furnace site. This thermophile is capable of producing thermostable endo-β-1,4-xylanase which cleaves xylan effectively. In the current study, this thermozyme was immobilized within a synthetic and a non-synthetic matrice for continuous production of metabolites using entrapment technique. The kinetic parameters of the free and immobilized enzyme were studied. For this purpose calcium alginate and polyacrylamide beads were prepared. Results: For the synthesis of immobilized beads, sodium alginate (40.0 gL-1) and calcium chloride (0.4 M) was used amalgamated. The temperature (50°C) and pH (7.0) optima of immobilized enzyme remained same for xylan hydrolysis however, the enzyme-substrate catalytic reaction time raised from 5.0 to 30.0 minutes as compared to free counterpart. Diffusion limit of high molecular weight xylan (corncob) caused a decline in Vmax of immobilized enzyme from 4773 to 203.7 U min-1 whereas, Km value increased from 0.5074 to 0.5722 mg ml-1 with reference to free enzyme. Immobilized endo-β-1,4-xylanase showed its stability at high temperatures as compared to free enzyme. It retained 18% and 9% residual activity at 70°C and 80°C, respectively whereas; free enzyme completely lost its activity at both temperatures. The Immobilized thermozyme displayed sufficient recycling efficiency and can be reused up to five reaction cycles, indicating that this enzyme can be a plausible candidate in paper processing industry. Conclusion: This thermozyme showed better immobilization yield and operational stability with the purpose of hydrolyzing the high molecular weight xylan. However, the enzyme immobilization properties can be improved further by immobilizing it on different supports for industrial purpose.

Keywords: immobilization, reusability, thermozymes, xylanase

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Authors: Djeddi Mabrouk

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The slow coming together between the Afro-Eurasia plates seems to be the main cause of the active deformation in the whole of North Africa which in consequence come true in Algeria with a large zone of deformation in an enough large limited band, southern through Saharan atlas and northern through tell atlas. Maghrebin and Atlassian Chain along North Africa are the consequence of this convergence. In junction zone, we have noticed a compressive regime NW-SE with a creases-faults structure and structured overthrust. From a geological point of view the north part of Algeria is younger then Saharan platform, it’s changing so unstable and constantly in movement, it’s characterized by creases openly reversed, overthrusts and reversed faults, and undergo perpetually complex movement vertically and horizontally. On structural level the north of Algeria it's a part of erogenous alpine peri-Mediterranean and essentially the tertiary age It’s spread from east to the west of Algeria over 1200 km.This oogenesis is extended from east to west on broadband of 100 km.The alpine chain is shaped by 3 domains: tell atlas in north, high plateaus in mid and Saharan atlas in the south In extreme south we find the Saharan platform which is made of Precambrian bedrock recovered by Paleozoic practically not deformed. The Algerian north and the Saharan platform are separated by an important accident along of 2000km from Agadir (Morocco) to Gabes (Tunisian). The seismic activity is localized essentially in a coastal band in the north of Algeria shaped by tell atlas, high plateaus, Saharan atlas. Earthquakes are limited in the first 20km of the earth's crust; they are caused by movements along faults of inverted orientation NE-SW or sliding tectonic plates. The center region characterizes Strong Earthquake Activity who locates mainly in the basin of Mitidja (age Neogene).The southern periphery (Atlas Blidéen) constitutes the June, more Important seism genic sources in the city of Algiers and east (Boumerdes region). The North East Region is also part of the tellian area, but it is characterized by a different strain in other parts of northern Algeria. The deformation is slow and low to moderate seismic activity. Seismic activity is related to the tectonic-slip earthquake. The most pronounced is that of 27 October 1985 (Constantine) of seismic moment magnitude Mw = 5.9. North-West region is quite active and also artificial seismic hypocenters which do not exceed 20km. The deep seismicity is concentrated mainly a narrow strip along the edge of Quaternary and Neogene basins Intra Mountains along the coast. The most violent earthquakes in this region are the earthquake of Oran in 1790 and earthquakes Orléansville (El Asnam in 1954 and 1980).

Keywords: alpine chain, seismicity north Algeria, earthquakes in Algeria, geophysics, Earth

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Authors: Vladimir Berezin, Andrey Bogoyavlenskiy, Pavel Alexyuk, Madina Alexyuk, Aizhan Turmagambetova, Irina Zaitseva, Nadezhda Sokolova, Elmira Omirtaeva

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Introduction: Triterpene saponins of plant origin are one of the most promising candidates for elaboration of novel adjuvants. Due to the combination of immunostimulating activity and the capacity interact with amphipathic molecules with formation of highly immunogenic nanocomplexes, triterpene saponins could serve as a good adjuvant/delivery system for vaccine use. In the research presented adjuvants on the base of nanocomplexes contained triterpene saponins isolated from Glycyrrhiza glabra and Saponaria officinalis plants indigenous to Kazakhstan were elaborated for influenza vaccine use. Methods: Purified triterpene saponins 'Glabilox' and 'SO1' with low toxicity and high immunostimulatory activity were isolated from plants Glycyrrhiza glabra L. and Saponaria officinalis L. by high-performance liquid chromatography (HPLC) and identified using electrospray ionization mass spectrometry (ESI-MS). Influenza virus A/St-Petersburg/5/09 (H1N1) propagated in 9-days old chicken embryos was concentrated and purified by centrifugation in sucrose gradient. Nanocomplexes contained lipids, and triterpene saponins Glabilox or SO1 were prepared by dialysis technique. Immunostimulating activity of experimental vaccine preparations was studied in vaccination/challenge experiments in mice. Results: Humoral and cellular immune responses and protection against influenza virus infection were examined after single subcutaneous and intranasal immunization. Mice were immunized subunit influenza vaccine (HA+NA) or whole virus inactivated influenza vaccine in doses 3.0/5.0/10.0 µg antigen/animal mixed with adjuvant in dose 15.0 µg/animal. Sera were taken 14-21 days following single immunization and mice challenged by A/St-Petersburg/5/09 influenza virus in dose 100 EID₅₀. Study of experimental influenza vaccine preparations in animal immunization experiments has shown that subcutaneous and intranasal immunization with subunit influenza vaccine mixed with nanocomplexes contained Glabilox or SO1 saponins stimulated high levels of humoral immune response (IgM, IgA, IgG1, IgG2a, and IgG2b antibody) and cellular immune response (IL-2, IL-4, IL-10, and IFN-γ cytokines) and resulted 80-90% protection against lethal influenza infection. Also, single intranasal and single subcutaneous immunization with whole virus inactivated influenza vaccine mixed with nanoparticulated adjuvants stimulated high levels of humoral and cellular immune responses and provided 100% protection against lethal influenza infection. Conclusion: The results of study have shown that nanocomplexes contained purified triterpene saponins Glabilox and SO1 isolated from plants indigenous to Kazakhstan can stimulate a broad spectrum of humoral and cellular immune responses and induce protection against lethal influenza infection. Both elaborated adjuvants are promising for incorporation to influenza vaccine intended for subcutaneous and intranasal routes of immunization.

Keywords: influenza vaccine, adjuvants, triterpene saponins, immunostimulating activity

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