bluuebunny/crossref_metadata_2025 huggingface dataset:
Exploring the Variability of Tropical Savanna Tree Structural Allometry with Terrestrial Laser Scanning
Authors: Luck Linda , Hutley Lindsay B. , Calders Kim , Levick Shaun R.
Published: November 2020

Individual tree carbon stock estimates typically rely on allometric scaling relationships established between field-measured stem diameter (DBH) and destructively harvested biomass. The use of DBH-based allometric equations to estimate the carbon stored over larger areas therefore, assumes that tree architecture, including branching and crown structures, are consistent for a given DBH, and that minor variations cancel out at the plot scale. We aimed to explore the degree of structural variation present at the individual tree level across a range of size-classes. We used terrestrial laser scanning (TLS) to measure the 3D structure of each tree in a 1 ha savanna plot, with coincident field-inventory. We found that stem reconstructions from TLS captured both the spatial distribution pattern and the DBH of individual trees with high confidence when compared with manual measurements (R2 = 0.98, RMSE = 0.0102 m). Our exploration of the relationship between DBH, crown size and tree height revealed significant variability in savanna tree crown structure (measured as crown area). These findings question the reliability of DBH-based allometric equations for adequately representing diversity in tree architecture, and therefore carbon storage, in tropical savannas. However, adoption of TLS outside environmental research has been slow due to considerable capital cost and monitoring programs often continue to rely on sub-plot monitoring and traditional allometric equations. A central aspect of our study explores the utility of a lower-cost TLS system not generally used for vegetation surveys. We discuss the potential benefits of alternative TLS-based approaches, such as explicit modelling of tree structure or voxel-based analyses, to capture the diverse 3D structures of savanna trees. Our research highlights structural heterogeneity as a source of uncertainty in savanna tree carbon estimates and demonstrates the potential for greater inclusion of cost-effective TLS technology in national monitoring programs.
Formation Mechanism for Upland Low-Relief Surface Landscapes in the Three Gorges Region, China
Authors: Lv Lingyun , Wang Lunche , Li Chang’an , Li Hui , Wang Xinsheng , Wang Shaoqiang
Published: November 2020

Extensive areas with low-relief surfaces that are almost flat surfaces high in the mountain ranges constitute the dominant geomorphic feature of the Three Gorges area. However, their origin remains a matter of debate, and has been interpreted previously as the result of fluvial erosion after peneplain uplift. Here, a new formation mechanism for these low-relief surface landscapes has been proposed, based on the analyses of low-relief surface distribution, swath profiles, χ mapping, river capture landform characteristics, and a numerical analytical model. The results showed that the low-relief surfaces in the Three Gorges area could be divided into higher elevation and lower elevation surfaces, distributed mainly in the highlands between the Yangtze River and Qingjiang River. The analyses also showed that the rivers on both sides of the drainage divide have not yet reached equilibrium, with actively migrating drainage divides and river basins in the process of reorganizing. It was concluded that the low-relief surfaces in the Three Gorges area did not share a common uplift history, and neither were they peneplain relicts, but rather that the effect of “area-loss feedback” caused by river capture has promoted the formation of upland low-relief surface landscapes. A future work aims to present the contribution of accurate dating of low-relief surface landscapes.
A Simple Spatio–Temporal Data Fusion Method Based on Linear Regression Coefficient Compensation
Authors: Bai Bingxin , Tan Yumin , Donchyts Gennadii , Haag Arjen , Weerts Albrecht
Published: November 2020

High spatio–temporal resolution remote sensing images are of great significance in the dynamic monitoring of the Earth’s surface. However, due to cloud contamination and the hardware limitations of sensors, it is difficult to obtain image sequences with both high spatial and temporal resolution. Combining coarse resolution images, such as the moderate resolution imaging spectroradiometer (MODIS), with fine spatial resolution images, such as Landsat or Sentinel-2, has become a popular means to solve this problem. In this paper, we propose a simple and efficient enhanced linear regression spatio–temporal fusion method (ELRFM), which uses fine spatial resolution images acquired at two reference dates to establish a linear regression model for each pixel and each band between the image reflectance and the acquisition date. The obtained regression coefficients are used to help allocate the residual error between the real coarse resolution image and the simulated coarse resolution image upscaled by the high spatial resolution result of the linear prediction. The developed method consists of four steps: (1) linear regression (LR), (2) residual calculation, (3) distribution of the residual and (4) singular value correction. The proposed method was tested in different areas and using different sensors. The results show that, compared to the spatial and temporal adaptive reflectance fusion model (STARFM) and the flexible spatio–temporal data fusion (FSDAF) method, the ELRFM performs better in capturing small feature changes at the fine image scale and has high prediction accuracy. For example, in the red band, the proposed method has the lowest root mean square error (RMSE) (ELRFM: 0.0123 vs. STARFM: 0.0217 vs. FSDAF: 0.0224 vs. LR: 0.0221). Furthermore, the lightweight algorithm design and calculations based on the Google Earth Engine make the proposed method computationally less expensive than the STARFM and FSDAF.
Analysis of the Suitability of High-Resolution DEM Obtained Using ALS and UAS (SfM) for the Identification of Changes and Monitoring the Development of Selected Geohazards in the Alpine Environment—A Case Study in High Tatras, Slovakia
Authors: Kovanič Ľudovít , Blistan Peter , Urban Rudolf , Štroner Martin , Blišťanová Monika , Bartoš Karol , Pukanská Katarína
Published: November 2020

The current trend in the use of remote sensing technologies is their use as a tool for monitoring hard-to-reach areas, objects or phenomena in the alpine environment. Remote sensing technology is also effectively used to monitor geohazards and the development of human-made changes in the country. Research presented in this study demonstrates the results for the usability of the publicly available national digital elevation model DEM 5.0 obtained by utilizing the airborne laser scanning (ALS) survey to monitor the development of erosion, morphological changes of talus cones, or the dynamics of movement of rock blocks between stages of measurement in the alpine environment of the High Tatras mountains. The reference methods for this study are the terrestrial laser scanning (TLS) and structure-from-motion (SfM) photogrammetric approach using unmanned aerial systems (UASs). By comparing the created DEMs, the ALS point cloud’s accuracy on mostly rocky areas of different sizes was verified. The results show that the standard deviation of the ALS point cloud ranges from 19 to 46 mm depending on the area’s size and characteristics. The maximum difference ranges from 100 to 741 mm. The value of systematic displacement of data obtained by different technologies ranges from 1 to 29 mm. This research confirms the suitability of the ALS method with its advantages and limits for the detection of movement of rock blocks or change of position of any natural or anthropogenic objects with a size from approximately 1 m2.
Marine Robots Mapping the Present and the Past: Unraveling the Secrets of the Deep
Authors: Kapetanović Nadir , Vasilijević Antonio , Nađ Đula , Zubčić Krunoslav , Mišković Nikola
Published: November 2020

Underwater cultural heritage sites are subject to constant change, whether due to natural forces such as sediments, waves, currents or human intervention. Until a few decades ago, the documentation and research of these sites was mostly done manually by diving archaeologists. This paper presents the results of the integration of remote sensing technologies with autonomous marine vehicles in order to make the task of site documentation even faster, more accurate, more efficient and more precisely georeferenced. It includes the integration of multibeam sonar, side scan sonar and various cameras into autonomous surface and underwater vehicles, remotely operated vehicle and unmanned aerial vehicle. In total, case studies for nine underwater cultural heritage sites around the Mediterranean region are presented. Each case study contains a brief archaeological background of the site, the methodology of using autonomous marine vehicles and sensors for their documentation, and the results in the form of georeferenced side-scan sonar mosaics, bathymetric models or reconstructed photogrammetric models. It is important to mention that this was the first time that any of the selected sites were documented with sonar technologies or autonomous marine vehicles. The main objective of these surveys was to document and assess the current state of the sites and to establish a basis on which future monitoring operations could be built and compared. Beyond the mere documentation and physical preservation, examples of the use of these results for the digital preservation of the sites in augmented and virtual reality are presented.
Pearson Correlation-Based Feature Selection for Document Classification Using Balanced Training
Authors: Nasir Inzamam Mashood , Khan Muhammad Attique , Yasmin Mussarat , Shah Jamal Hussain , Gabryel Marcin , Scherer Rafał , Damaševičius Robertas
Published: November 2020

Documents are stored in a digital form across several organizations. Printing this amount of data and placing it into folders instead of storing digitally is against the practical, economical, and ecological perspective. An efficient way of retrieving data from digitally stored documents is also required. This article presents a real-time supervised learning technique for document classification based on deep convolutional neural network (DCNN), which aims to reduce the impact of adverse document image issues such as signatures, marks, logo, and handwritten notes. The proposed technique’s major steps include data augmentation, feature extraction using pre-trained neural network models, feature fusion, and feature selection. We propose a novel data augmentation technique, which normalizes the imbalanced dataset using the secondary dataset RVL-CDIP. The DCNN features are extracted using the VGG19 and AlexNet networks. The extracted features are fused, and the fused feature vector is optimized by applying a Pearson correlation coefficient-based technique to select the optimized features while removing the redundant features. The proposed technique is tested on the Tobacco3482 dataset, which gives a classification accuracy of 93.1% using a cubic support vector machine classifier, proving the validity of the proposed technique.
Bio- and Biomimetic Receptors for Electrochemical Sensing of Heavy Metal Ions
Authors: Stortini Angela Maria , Baldo Maria Antonietta , Moro Giulia , Polo Federico , Moretto Ligia Maria
Published: November 2020

Heavy metals ions (HMI), if not properly handled, used and disposed, are a hazard for the ecosystem and pose serious risks for human health. They are counted among the most common environmental pollutants, mainly originating from anthropogenic sources, such as agricultural, industrial and/or domestic effluents, atmospheric emissions, etc. To face this issue, it is necessary not only to determine the origin, distribution and the concentration of HMI but also to rapidly (possibly in real-time) monitor their concentration levels in situ. Therefore, portable, low-cost and high performing analytical tools are urgently needed. Even though in the last decades many analytical tools and methodologies have been designed to this aim, there are still several open challenges. Compared with the traditional analytical techniques, such as atomic absorption/emission spectroscopy, inductively coupled plasma mass spectrometry and/or high-performance liquid chromatography coupled with electrochemical or UV–VIS detectors, bio- and biomimetic electrochemical sensors provide high sensitivity, selectivity and rapid responses within portable and user-friendly devices. In this review, the advances in HMI sensing in the last five years (2016–2020) are addressed. Key examples of bio and biomimetic electrochemical, impedimetric and electrochemiluminescence-based sensors for Hg2+, Cu2+, Pb2+, Cd2+, Cr6+, Zn2+ and Tl+ are described and discussed.
Near-Field Measurement of Six Degrees of Freedom Mining-Induced Tremors in Lower Silesian Copper Basin
Authors: Fuławka Krzysztof , Pytel Witold , Pałac-Walko Bogumiła
Published: November 2020

The impact of seismicity on structures is one of the key problems of civil engineering. According to recent knowledge, the reliable analysis should be based on both rotational and translational components of the seismic wave. To determine the six degrees of freedom (6-DoF) characteristic of mining-induced seismicity, two sets of seismic posts were installed in the Lower Silesian Copper Basin, Poland. Long-term continuous 6-DoF measurements were conducted with the use of the R-1 rotational seismometer and EP-300 translational seismometer. In result data collection, the waveforms generated by 39 high-energy seismic events were recorded. The characteristic of the rotational component of the seismic waves were described in terms of their amplitude and frequency characteristics and were compared with translational measurements. The analysis indicated that the characteristic of the rotational component of the seismic wave differs significantly in comparison to translational ones, both in terms of their amplitude and frequency distribution. Also, attenuation of rotational and translational components was qualitatively compared. Finally, the empirical formulas for seismic rotation prediction in the Lower Silesian Copper Basin were developed and validated.
Grounded Theory as an Approach for Exploring the Effect of Cultural Memory on Psychosocial Well-Being in Historic Urban Landscapes
Authors: Hussein Fatmaelzahraa , Stephens John , Tiwari Reena
Published: November 2020

Although grounded theory (GT) has emerged as a popular research approach across multiple areas of social science, it has been less widely taken up by researchers working in the fields of urban planning and design. The application of GT enables uniquely innovative insights to be gained from qualitative data, but it has attracted criticism and brings its own challenges. This paper proposes a methodology that could be applied by other researchers in the field of urban research. Utilising constructivist GT as a qualitative approach, this research investigates how cultural memory impacts the psychosocial well-being and quality of life (QoL) of users of, and visitors to, historic urban landscapes (HULs). Based on the findings, it can be posited that the application of GT yields a rich and nuanced understanding of how users of HULs experience the settings in which they live, and the impact and significance on human psychosocial well-being of the cultural memories incarnated within such settings. The current paper also contends that GT enables researchers studying the built environment to construct inductively based theories. Lastly, the practical implications of developing GT for application to HUL management are discussed, both in regard to how users experience the contexts in which they live and the impact of such contexts on well-being and quality of life.
Assessment of Sustainable Mobility by MCDM Methods in the Science and Technology Parks of Vilnius, Lithuania
Authors: Zapolskytė Simona , Vabuolytė Vaida , Burinskienė Marija , Antuchevičienė Jurgita
Published: November 2020

The development of science and technology parks (STPs) has become a trendy tool for promoting the economy, innovation, and technology for more than 30 years worldwide. However, STPs poses challenges for urban planners seeking a vision of sustainable urban development. These places become an object of attraction for many highly skilled workers who create daily traffic flows. The proper accessibility and provision of transport infrastructure and services become the challenge for the development of such places because the availability of services influences the choice of travel mode and the possible employees’ travel behaviour. The authors of the research aim to assess the level of development of infrastructure and transport services conducive to the sustainable mobility of science and technology park staff in Vilnius city. Changing mobility behaviour into a more sustainable way is of interest to many scientists and practitioners, so the authors think that STP staff can represent a group of educated, working-age stakeholders within the city population, who has an interest in sustainable mobility travel options and can set an example of sustainable travel. Besides, recommendations for the planning and sustainable development from the sustainable urban mobility point of view of science and technology parks and similar institutions are provided. To achieve this goal, the authors use scientific empirical and theoretical research as well as multi-criteria decision-making (MCDM) methods. The results show the link between the distance from the developed STP site to the city centre and the more sustainable mobility of workers. Therefore, it is suggested to develop STPs closer to the urban centre as it often does not require large-scale development, nor do they engage in the polluting industry. Moreover, the authors suggest the key criteria that should be considered for STP development.
The Influence of Database Selection on Environmental Impact Results. Life Cycle Assessment of Packaging Using GaBi, Ecoinvent 3.6, and the Environmental Footprint Database
Authors: Pauer Erik , Wohner Bernhard , Tacker Manfred
Published: November 2020

This research analyses the differences in impact assessment results depending on the choice of a certain software-database combination. Six packaging systems were modelled in three software-database combinations (GaBi database in GaBi software, ecoinvent 3.6 database in openLCA, Environmental Footprint database in openLCA). The chosen Life Cycle Impact Assessment (LCIA) method is EF 2.0. Differences and errors in the implementation of the LCIA method are a possible source of deviations. We compared the published characterisation factors with the factors implemented in the software-database combinations. While results for the climate change category are similar between the different databases, this is not the case for the other impact categories. In most cases, the use of the ecoinvent 3.6 database leads to higher results compared to GaBi. This is partly due to the fact, that ecoinvent datasets often include more background processes than the corresponding GaBi datasets. We found striking discrepancies in LCIA implementation, including the lack of regionalisation for water use in ecoinvent. A meaningful communication of LCIA results requires an excellent knowledge of the analysed product system, as well as of database quality issues and LCIA methodology. We fully acknowledge the constant efforts of database providers to improve their databases.
Contributions from Social Theory to Sustainability for All
Authors: Flecha Ramon
Published: November 2020

The sustainability of societies is an issue of utmost importance for humankind. This is reflected in the 17 Sustainable Development Goals, which highlight the main challenges that citizens face, including underserved groups, and set the path for finding solutions to overcome them. The achievement of the SDGs for 2030 is setting not only the political agenda, but also the scientific one. From the field of social sciences, an issue that remains underexplored is the contributions (or lack thereof, in some occasions) from social theory to the consolidation of more sustainable societies, including the underserved groups. In this vein, the aim of this article is to provide robust evidence on how social theory has contributed to such improvement and is still doing it. To this end, it provides an analysis of how the advancements made from social theory with social impact have contributed to the achievement of the SDGs. Alongside, this article also presents how some theories that never had social impact at their core have hindered the improvement of societies. This dual approach provides a clear picture of the role that social theory can play in the achievement of the SDGs, as well as evidence towards the overcoming of exclusionary theories with no scientific basis.
Cost–Benefit Analysis of Municipal Sludge as a Low-Grade Nutrient Source: A Case Study from South Africa
Authors: Tesfamariam Eyob Habte , Ogbazghi Zekarias Mihreteab , Annandale John George , Gebrehiwot Yemane
Published: November 2020

Municipal sludge has economic value as a low-grade fertilizer as it consists of appreciable amounts of the macro and micronutrients. When using sludge as fertilizer, the economic aspect should be taken into account. In this study, the following specific objectives were identified: (a) to investigate the economic feasibility of using sludge as a fertilizer; (b) to estimate the maximum economic distance sludge can be transported as a fertilizer; and (c) to test the economic feasibility of selling sludge using commercial inorganic fertilizer as a bench mark. The study showed that for anaerobically digested, paddy dried, municipal sludge consisting of 3% N, 2% P, and 0.3% K the economic feasibility of transporting the sludge was limited to a diameter of 20 km in the arid zone, 28 km in the semi-arid zone, 51 km in the sub humid zone, 66 km in the humid zone, and 75 km in the super-humid zone. Therefore, the economic feasibility of using sludge as a substitute for or complementary to commercial inorganic fertilizer is dictated by the distance between the wastewater care work and the farm, sludge nutrient concentration, agro-ecological zone (rain and temperature), and the real-time commercial inorganic fertilizer price.
Is Knowledge of Circular Economy, Pro-Environmental Behavior, Satisfaction with Life, and Beliefs a Predictor of Connectedness to Nature in Rural Children and Adolescents? A Pilot Study
Authors: Solano-Pinto Natalia , Garrido Dunia , Gértrudix-Barrio Felipe , Fernández-Cézar Raquel
Published: November 2020

Sustainable development (SD) is crucial to maintaining and preserving the planet we live on. The new paradigm of circular economy (CE) corresponds to the sustainable development goals and includes environmental, economic, and social dimensions. The United Nations has set quality education and the search for good health and well-being in the long term as tools for achieving SD. This study aims to identify the predictors of connectedness to nature in children and adolescents using knowledge of CE, pro-environmental behavior, beliefs about caring for the environment, and satisfaction with life as possible predictive variables. The exploration of the influence of these predictors on connectedness to nature, taking sex and age as covariates, was performed using a binary logistic regression model. We found that low scores on pro-environmental behavior, satisfaction with life, knowledge of waste management and CE, and beliefs about environmental behavior were related to a low degree of connectedness to nature. Thus, our findings suggest that the educational system must promote not only the assimilation of knowledge and beliefs but also satisfaction with life given its relationship with connectedness to nature.
Innovative Methodologies in a Pandemic: The VESS Model
Authors: Romero-Esquinas María Helena , Muñoz-González Juan Manuel , Hidalgo-Ariza María Dolores
Published: November 2020

The VESS (Meaningful Life with Balance and Wisdom) model is considered to be a learning method based on the construction of knowledge through critical and visible thinking, with a neuroeducational base. The aim of the present work is to conduct a psychometric study of a measurement scale about the learning of the VESS model created for teachers-in-training. This article presents two survey-based descriptive studies conducted at the University of Cordoba (Spain). The data were subjected to descriptive, correlational, reliability and validity analysis through exploratory and confirmatory analyses, respectively. It is an instrument with high goodness-of-fit indices and suitable validity and reliability values. This instrument is applicable to similar study contexts.
A multi-Criteria Wetland Suitability Index for Restoration across Ontario’s Mixedwood Plains
Authors: Medland Sally J. , Shaker Richard R. , Forsythe K. Wayne , Mackay Brian R. , Rybarczyk Greg
Published: November 2020

Significant wetland loss (~72%; 1.4 million hectares) in the Province of Ontario, Canada, has resulted in damage to important ecosystem services that mitigate the effects of global change. In response, major agencies have set goals to halt this loss and work to restore wetlands to varying degrees of function and area. To aid those agencies, this study was guided by four research questions: (i) Which physical and ecological landscape criteria represent high suitability for wetland reconstruction? (ii) Of common wetland suitability metrics, which are most important? (iii) Can a multi-criteria wetland suitability index (WSI) effectively locate high and low wetland suitability across the Ontario Mixedwood Plains Ecozone? (iv) How do best sites from the WSI compare and contrast to both inventories of presettlement wetlands and current existing wetlands? The WSI was created based on seven criteria, normalized from 0 (low suitability) to 10 (high suitability), and illustrated through a weighted composite raster. Using an Analytical Hierarchy Process (AHP) and importance determined from a scoping review of relevant literature, soil drainage had the greatest meaning and weight within the WSI (48.2%). The Getis-Ord Gi* index charted statistically significant “hot spots” and “cold spots” of wetland suitability. Last, the overlay analysis revealed greater similarity between high suitability sites and presettlement wetlands supporting the severity of historic wetland cannibalization. In sum, this transferable modeling approach to regional wetland restoration provides a prioritization tool for improving ecological connectivity, services, and resilience.
Strongly Lensed Supernovae in Well-Studied Galaxy Clusters with the Vera C. Rubin Observatory
Authors: Petrushevska Tanja
Published: November 2020

Strong lensing by galaxy clusters can be used to significantly expand the survey reach, thus allowing observation of magnified high-redshift supernovae that otherwise would remain undetected. Strong lensing can also provide multiple images of the galaxies that lie behind the clusters. Detection of strongly lensed Type Ia supernovae (SNe Ia) is especially useful because of their standardizable brightness, as they can be used to improve either cluster lensing models or independent measurements of cosmological parameters. The cosmological parameter, the Hubble constant, is of particular interest given the discrepancy regarding its value from measurements with different approaches. Here, we explore the feasibility of the Vera C. Rubin Observatory Legacy Survey of Space and Time (LSST) of detecting strongly lensed SNe in the field of five galaxy clusters (Abell 1689 and Hubble Frontier Fields clusters) that have well-studied lensing models. Considering the 88 systems composed of 268 individual multiple images in the five cluster fields, we find that the LSST will be sensitive to SNe Ia (SNe IIP) exploding in 41 (23) galaxy images. The range of redshift of these galaxies is between 1.01<z<3.05. During its 10 years of operation, LSST is expected to detect 0.2±0.1 SN Ia and 0.9±0.3 core collapse SNe. However, as LSST will observe many more massive galaxy clusters, it is likely that the expectations are higher. We stress the importance of having an additional observing program for photometric and spectroscopic follow-up of the strongly lensed SNe detected by LSST.
Unexpected Encapsulation of Selected Polycyclic Aromatic Hydrocarbons by β-Cyclodextrin Studied Using UV-Vis Spectrophotometry, Micro-Planar Chromatography and Temperature Dependent Inclusion Chromatography
Authors: Kaleniecka Aleksandra , Włodarczyk Elżbieta , Piaskowski Krzysztof , Lewandowska Lucyna , Zarzycki Paweł K.
Published: November 2020

This research communication significantly extends our previous studies focusing on the temperature effects related to the unexpected chromatographic behavior of 1-acenaphthenol in the presence of native β-cyclodextrin (β-CD) additive, working under thin-layer chromatographic (TLC) conditions. We have applied complementary and orthogonal techniques including (i) temperature-controlled ultraviolet-visible (UV-VIS) spectroscopy, (ii) thermostated microplanar high-performance chromatography (micro-HPTLC) and (iii) temperature-dependent inclusion chromatography based on high-performance liquid chromatography (HPLC) to investigate the retention behavior of related host molecules. Particularly, various symmetric and asymmetric molecules were tested, such as: naphthalene and its derivatives including acenaphthylene, acenaphthene and selected dimethynaphthalenes: 1,8-DMN, 1,5-DMN, 2,3-DMN and 2,6-DMN. Reported raw experimental data, particularly performed in liquid phase and detected by UV-Vis spectrophotometry, may suggest that solubility changes of the supramolecular complexes studied and differences in total analysis time between TLC and HPLC separation can trigger strong retention of target components in planar chromatographic systems. This was also supported by principal component analysis (PCA) of the multi-source data obtained. It is hoped that the reported analyses enable the adjustment of phenomenological models describing liquid chromatography retention and the solubility behavior of low-molecular mass guest molecules, controlled by supramolecular interactions with selected macrocycles. It should be noted that the reported phenomenon, specifically supramolecular complexes precipitation, may have a number of practical applications. This can be used to improve the efficiency and selectivity of planar and/or microfluidic systems. On the other hand, precipitation via host-guest interactions may be applied for highly selective water purification technological processes that will be designed for the removal of given organic micropollutants.
Gymnodimine A and 13-desMethyl Spirolide C Alter Intracellular Calcium Levels via Acetylcholine Receptors
Authors: Nieva Joyce A. , Krock Bernd , Tillmann Urban , Tebben Jan , Zurhelle Christian , Bickmeyer Ulf
Published: November 2020

Gymnodimines and spirolides are cyclic imine phycotoxins and known antagonists of nicotinic acetylcholine receptors (nAChRs). We investigated the effect of gymnodimine A (GYM A) and 13-desmethyl spirolide C (SPX 1) from Alexandrium ostenfeldii on rat pheochromocytoma (PC12) cells by monitoring intracellular calcium levels ([Ca]i). Using whole cells, the presence of 0.5 µM of GYM A or SPX 1 induced an increase in [Ca]i mediated by acetylcholine receptors (AChRs) and inhibited further activation of AChRs by acetylcholine (ACh). To differentiate the effects of GYM A or SPX 1, the toxins were applied to cells with pharmacologically isolated nAChRs and muscarinic AChRs (mAChRs) as mediated by the addition of atropine and tubocurarine, respectively. GYM A and SPX 1 activated nAChRs and inhibited the further activation of nAChRs by ACh, indicating that both toxins mimicked the activity of ACh. Regarding mAChRs, a differential response was observed between the two toxins. Only GYM A activated mAChRs, resulting in elevated [Ca]i, but both toxins prevented a subsequent activation by ACh. The absence of the triketal ring system in GYM A may provide the basis for a selective activation of mAChRs. GYM A and SPX 1 induced no changes in [Ca]i when nAChRs and mAChRs were inhibited simultaneously, indicating that both toxins target AChRs.
Relative Frequency of Blastocystis Subtypes 1, 2, and 3 in Urban and Periurban Human Populations of Arequipa, Peru
Authors: Ascuña-Durand Kasandra , Salazar-Sánchez Renzo S. , Castillo-Neyra Ricardo , Ballón-Echegaray Jorge
Published: November 2020

Blastocystis is one of the most common protozoa found in the human gut and are genetically diverse and widely distributed around the world. Nonspecific and inconsistent symptoms have been associated with this protozoon; thus, its clinical importance remains controversial. Our aim was to estimate the relative frequency of Blastocystis subtypes 1, 2, and 3, which are the predominant subtypes reported in South America, based on conserved regions of SSU rDNA sequences and determine the factors associated with them. A total of 116 Blastocystis-positive stool samples were processed using conventional PCR with Blastocystis-specific primers. We identified subtype 1 (10.3%), subtype 2 (7.8%), subtype 3 (25.0%), and mixed subtype infections (8.7%). However, we could not identify any Blastocystis subtypes in 48.3% of the samples; therefore, it is likely that other subtypes were present in the area. No association was found between any gastrointestinal symptom and single or mixed Blastocystis subtypes. We found a statistically significant association between Blastocystis subtype 2 and irritable bowel syndrome (OR = 17.8, 95% CI = 1.5–408.4, p = 0.039); however, the number of samples with IBS was small (n= 4). There was no association between the Blastocystis subtypes and any epidemiological variable studied. In rural populations, we only identified subtype 1, while in urban and periurban populations, we identified subtypes 1, 2, and 3.
Neutrino-Mass Sensitivity and Nuclear Matrix Element for Neutrinoless Double Beta Decay
Authors: Ejiri Hiroyasu
Published: November 2020

Neutrinoless double beta decay (DBD) is a useful probe to study neutrino properties such as the Majorana nature, the absolute neutrino mass, the CP phase and the others, which are beyond the standard model. The nuclear matrix element (NME) for DBD is crucial to extract the neutrino properties from the experimental transition rate. The neutrino-mass sensitivity, i.e., the minimum neutrino-mass to be measured by the DBD experiment, is very sensitive to the DBD NME. Actually, the NME is one of the key elements for designing the DBD experiment. Theoretical evaluation for the DBD NME, however, is very hard. Recently experimental studies of charge-exchange nuclear and leptonic reactions have shown to be used to get single-β NMEs associated with the DBD NME. Critical discussions are made on the neutrino-mass sensitivity and the NME for the DBD neutrino-mass study and on the experimental studies of the single-β NMEs and nuclear structures associated with DBD NMEs.
The Lipid Transfer Protein 1 from Nicotiana benthamiana Assists Bamboo mosaic virus Accumulation
Authors: Chiu Ling-Ying , Chen I-Hsuan , Hsu Yau-Heiu , Tsai Ching-Hsiu
Published: November 2020

Host factors play a pivotal role in regulating virus infection. Uncovering the mechanism of how host factors are involved in virus infection could pave the way to defeat viral disease. In this study, we characterized a lipid transfer protein, designated NbLTP1 in Nicotiana benthamiana, which was downregulated after Bamboo mosaic virus (BaMV) inoculation. BaMV accumulation significantly decreased in NbLTP1-knockdown leaves and protoplasts compared with the controls. The subcellular localization of the NbLTP1-orange fluorescent protein (OFP) was mainly the extracellular matrix. However, when we removed the signal peptide (NbLTP1/ΔSP-OFP), most of the expressed protein targeted chloroplasts. Both NbLTP1-OFP and NbLTP1/ΔSP-OFP were localized in chloroplasts when we removed the cell wall. These results suggest that NbLTP1 may have a secondary targeting signal. Transient overexpression of NbLTP1 had no effect on BaMV accumulation, but that of NbLTP1/ΔSP significantly increased BaMV expression. NbLTP1 may be a positive regulator of BaMV accumulation especially when its expression is associated with chloroplasts, where BaMV replicates. The mutation was introduced to the predicted phosphorylation site to simulate the phosphorylated status, NbLTP/ΔSP/P(+), which could still assist BaMV accumulation. By contrast, a mutant lacking calmodulin-binding or simulates the phosphorylation-negative status could not support BaMV accumulation. The lipid-binding activity of LTP1 was reported to be associated with calmodulin-binding and phosphorylation, by which the C-terminus functional domain of NbLTP1 may play a critical role in BaMV accumulation.
Numerical Study of the Interaction between a Collapsing Bubble and a Movable Particle in a Free Field
Authors: Zheng Yuxin , Chen Linya , Liang Xiaoyu , Duan Hangbo
Published: November 2020

This study numerically investigates the interactions between a collapsing bubble and a movable particle with a comparable size in a free field, which is associated with the microscopic mechanisms of the synergetic effects of cavitation erosion and particle abrasion on the damages of materials in fluid machineries. A new solver on OpenFOAM based on direct numerical simulations with the volume of fluid (VOF) method capturing the interface of a bubble and with the overset grid method handling the motion of the particle was developed to achieve the fluid–structure interaction (FSI). The results show that bubbles in cases with stand-off parameter χ (defined as (d0−Rp)/R0), where d0 is the initial distance between the centers of the bubble and particle, and Rp,R0 are the particle’s radius and the initial radius of the bubble respectively >1, experience spherical-shaped collapse under the influence of the approaching particle, which is attracted by the collapsing bubble. The bubbles in these cases no longer present non-spherical collapse. Additionally, a force balance model to account for the particle dynamics was established, in which the particle velocity inversely depends on the size of the particle, and approximately on the second power of the initial distance from the bubble. This analytical result accords with the numerical results and is valid for cases with χ>1 only, since it is based on the theory of spherical bubbles. These conclusions are important for further study of the interactions between a bubble and a movable particle near a rigid wall.
Assessment of the Effluents of Basra City Main Water Treatment Plants for Drinking and Irrigation Purposes
Authors: Almuktar Suhad , Hamdan Ahmed Naseh Ahmed , Scholz Miklas
Published: November 2020

A severe water scarcity challenge is facing Iraq, which is predominantly due to the absence of water management policies, negatively impacting the water quantity and quality provision from the Tigris and Euphrates Rivers. Moreover, these practices have led to the intrusion of the Arabian Gulf salinity wedge into the Shatt Al-Arab River (SAR), which is the main water source for most water treatment plants (WTPs) in Basra city. In addition, the inadequate management and operation for most WTPs is another reason for the deterioration of water quality provided to Basra province. Accordingly, the aim of this study is to evaluate the performance of the main WTP within Basra province and to subsequently make recommendations for decision-makers to come up with new management strategies and policies. The effluents from eight WTPs were selected to study the quality of water supply for Basra city during the period between January 2018 and December 2018. The results showed that all WTPs were inadequate to treat raw water for drinking or irrigation purposes mainly due to the very bad raw water quality provided by the SAR as well as the lack of maintenance for such plants, resulting in very low removal efficiencies for various water contaminants.
Deficit Irrigation as a Suitable Strategy to Enhance the Nutritional Composition of HydroSOS Almonds
Authors: Gutiérrez-Gordillo Saray , Lipan Leontina , Durán Zuazo Víctor Hugo , Sendra Esther , Hernández Francisca , Hernández-Zazueta Martín Samuel , Carbonell-Barrachina Ángel A. , García-Tejero Iván Francisco
Published: November 2020

The Mediterranean region is one of the most water-scarce areas worldwide and is considered a climate-change hotspot. To assure the viability and competitiveness of irrigated agriculture, it is vital to implement strategies that can maximize water saving without compromising yield. Deficit irrigation (DI) for cultivating drought-tolerant species such as almond (Prunus dulcis (Mill.) D.A. Webb) can help in achieving this goal, while at the same time improving fruit chemical composition. This work evaluated the effect of DI techniques and cultivars on the chemical composition of almonds (cvs. Marta, Guara, and Lauranne) in order to elucidate the most suitable irrigation dose under water-scarcity scenarios. Three irrigation regimes were imposed: a control treatment (FI), which was fully irrigated, receiving 100% of the irrigation requirement (IR), and two sustained-deficit irrigation (SDI) strategies that received 75% (SDI75) and 65% (SDI65) of IR. Significant differences among cultivars and irrigation treatments were observed for antioxidant activity and organic acid, sugar, and fatty acid content, which were increased by the SDI strategies. In addition, highly significant correlations were found between leaf-water potential and components such as fumaric acid, sugars, and fatty acids. In terms of the cultivars, cv. Marta showed the highest antioxidant activity, cv. Guara was the richest in organic acids, and cv. Lauranne had the highest fatty acid content. Consequently, SDI strategies improved almond quality parameters related to their nutritional and sensory composition, with significant water savings (reductions of 25–35%) and without important yield loss.
Mycobacterium avium Complex (MAC) in Water Distribution Systems and Household Plumbing in the United States
Authors: Falkinham Joseph O.
Published: November 2020

Members of the Mycobacterium avium complex (MAC) are waterborne, opportunistic pathogens whose characteristics make urban water distribution systems and household plumbing ideal habitats for their survival, persistence and growth. Rather than contaminants, MAC are colonists of drinking water systems. MAC are normal inhabitants of natural soils and water, and enter drinking water treatment systems through surface sources. A proportion of MAC survive transmission through the treatment plant, and regrow in the distribution system and household plumbing. Once within household plumbing, MAC adhere to surfaces and form biofilms, thus preventing their washout. The thermal tolerance of MAC leads to growth in water heating systems. Stagnation does not reduce MAC numbers, as MAC can grow at low oxygen levels. MAC present challenges to current water monitoring approaches as their numbers do not correlate with E. coli, fecal coliforms or heterotrophic plate count bacteria.
Influence of Erodible Beds on Shallow Water Hydrodynamics during Flood Events
Authors: Santillán David , Cueto-Felgueroso Luis , Sordo-Ward Alvaro , Garrote Luis
Published: November 2020

Flooding has become the most common environmental hazard, causing casualties and severe economic losses. Mathematical models are a useful tool for flood control, and current computational resources let us simulate flood events with two-dimensional (2D) approaches. An open question is whether bed erosion must be accounted for when it comes to simulating flood events. In this paper we answer this question through numerical simulations using the 2D depth-averaged shallow-water equations. We analyze the effect of mobile beds on the flow patterns during flood events. We focus on channel confluences where water flow and sediment mobilization have a marked 2D behavior. We validate our numerical simulations with laboratory experiments of erodible beds with satisfactory results. Moreover, our sensitivity analysis indicates that the bed roughness model has a great influence on the simulated erosion and deposition patterns. We simulate the sediment transport and its influence on the water flow in a real river confluence during flood events. Our simulations show that the erosion and deposition processes play an important role on the water depth and flow velocity patterns. Accounting for the mobile bed leads to smoother water depth and velocity fields, as abrupt fields for the non-erodible model emerge from the irregular bed topography. Our study highlights the importance of accounting for erosion in the simulation of flood events, and the impact on the water depth and velocity fields.
Effect of Oxyjun™ on Adipose Tissue Inflammation - A Randomized, Placebo-Controlled Clinical Study
Authors: Srivastava Shalini , Girandola Robert , Kokate Ankul Suresh
Published: November 2020

The aim of the study was to evaluate the effect of Oxyjun™ on cardiovascular fitness of overweight individuals by reducing obesity induced systemic inflammation. Male participants between the ages of 18 - 35 years and body mass index of 25 - 34.9 kg/m2 were recruited in the study. Change in neutrophil lymphocyte ratio (NLR), high density lipoprotein (HDL-c) and quality of life using 36-item Short form survey (SF-36) was assessed over a period of 8-weeks. Results demonstrated that NLR was reduced by 0.71 in Oxyjun™ and by 0.42 in the placebo group at the end of study period. Also, within group comparison was significant for Oxyjun™ group when compared from baseline; p<0.001. Further, HDL-c levels were increased in the OxyjunTM group by 4.04 mg/dL and reduced for the placebo group by 1.22 mg/dL when compared from baseline; p=0.09. For SF-36 quality of life assessments, the health concepts of fatigue, mental health, and social function showed significant improvement and no adverse or serious adverse events were reported for both groups during the course of the study. In conclusion, Oxyjun™ when consumed for 8-weeks reduced NLR of study volunteers thereby demonstrating its potential for lowering obesity induced systemic inflammation. Oxyjun™ also increased HDL levels that could further promote cardiovascular fitness and prevent the risk of cardiovascular events.
MTHFR rs1801133 polymorphism in Bangladeshi population – its prevalence and detection
Authors: Khan Sumaiya Farah , Akter Mahmuda , Shahriar Shayan , Hossain MD Amzad , Sajib Abu Ashfaqur
Published: November 2020

Methylenetetrahydrofolate reductase (MTHFR) has been reported as a key enzyme not only for intracellular folate homeostasis but also for metabolism. A particular variant (G677A) leads to an altered amino acid, which ultimately causes decreased enzyme activity and may modulate the risk of causing several chronic diseases. The purpose of this study was to detect the pervasiveness of this variant MTHFR rs1801133 G677A in the Bangladeshi population. We applied allele-specific polymerase chain reaction (AS-PCR) to determine the genotypes at the rs1801133 in the Bangladeshi population. We performed targeted sequencing of the AS-PCR product of randomly selected samples. Out of the 181 Bangladeshi individuals, 71.8% had homozygous 677GG genotype, while 28.2% comprised of heterozygous 677GA genotype. No individual with the homozygous 677AA genotype was found in this representative Bangladeshi population. The 677G alleles had higher frequency (0.856) compared to 677A alleles (0.144) at the rs1801133 locus. Though the more risky homozygous 677AA genotype at the rs1801133 locus is absent in the Bangladeshi population, further association studies can be performed to identify the role of MTHFR mutation in the susceptibility to different multifactorial diseases.