bluuebunny/crossref_metadata_2025 huggingface dataset:
Bridging Agents Optimization Based on Predicting Induced Fracture Model for Deviated Wells – A Case Study
Authors: Karimi Rad Mohammad Saeed , Kalhor Mohammadi Mojtaba , Tahmasbi Nowtarki Kourosh
Published: June 2021

Applying bridging agents to prevent seepage losses is a common practice during drilling reservoir sections which limits the invaded zone and reduces stuck pipe possibility. Unfortunately, the initial particle size distribution (PSD) design of bridging agents based on static models does not prevent actual seepage losses due to the induced fractures which have different sizes comparing to the initial reservoir pore sizes.

This paper reviews an actual case study with provided solutions in an offshore field located in the Middle East which had a seepage loss circulation problem through induced fractures. It also presents analyzing natural and induced fractures size of the reservoir layer to choose optimized possible bridging agents’ PSD to cure/prevent loss circulation problems. The maximum/average pore size of formation can be measured from routine core analyses. A geological method to estimate the induced fracture widths with geo-mechanical data were used. Finally, optimum blends of bridging agents for loss circulation pills or background treatment to prevent mentioned problems were designed.

Based on the laboratory testing on cores taken from previously-drilled wells in the mentioned field, the maximum size of pore throats was measured as 20 microns. Therefore, using the Ideal Packing Theory (IPT) method, the result for selecting bridging agents through pore throats (for seepage loss) indicates that optimum treatment is using of bridging agents with D50 and D90 6.5 and 16 microns, respectively.

Also, for improving the treatment selection through parameters such as PSD of bridging agents, investigation on behavior of fracture growth were done. As a result, induced fracture width in studied well, with provided geo-mechanical (such as Poisson's Ratio & Young Modulus) and drilling fluid data was calculated approximately to be 230 microns through the porous medium in the near-wellbore region. Therefore, optimization for bridging these new fractures while drilling was performed again and it was concluded that optimum bridging agent size distribution at the tip of these newly-created induced fractures is applying bridging agents with D50 and D90 of 64 and 170 microns respectively, which are approximately 10 times higher than normal treatment in size.

This paper describes the historical seepage circulation and related problems in the mentioned field and presents a methodology to prevent these issues by predicting induced fractures and optimizing bridging agent PSD to block them. Considering this methodology, the gap between the design and actual drilling is reduced and both rig downtime and related drilling and drilling fluids costs can be saved.
Improving Accuracy of Checkshot Time-Depth by Applying Advanced Model-Based Correction for Rig-Source Survey on a Highly Inclined Well
Authors: Nguyen The , Iamboon Jakkarin , Nampratchayakul Piyanuch , Tongpan Nirut , Yint Htun Ye , Tran Dong
Published: June 2021

In seismic exploration, checkshot survey is an important method to obtain accurate time-depth profile for depth-to-time or time-to-depth conversion. However, the standard geometry correction for a rig-source survey in a high-inclination well will not provide a reliable time-depth result due to ray-bending effect. The objective of this study was to enhance the accuracy of the time-depth velocity by utilizing an advanced technique called model-based correction or pseudo walk-above simulation.

To obtain model-based vertical times, a flat-layered velocity model was built by using the checkshot velocities as initial guess. The model was then inverted to match the observed checkshot travel times, which were the actual measurement of travel path from source to receivers. The model was iterated to minimize the residual between the observed and modeled travel times in a least-square sense. A pseudo walk-above checkshot simulation was run on the inverted model by positioning the sources exactly on top of the receivers to get the vertical times, which were used for the final time-depth relationship and further image processing.

The residual times of less than 1 millisecond (ms) were observed between the actual measured transit times and modeled travel times from a fixed source to the receivers in the inverted model. This demonstrated the inverted model was realiable to use for obtaining more accurate vertical time-depth through pseudo walk-above checkshot simulation. This optimal inverted model was considered as the best estimation of the true earth model in this case. A comparison of modeled vertical times estimated through the pseudo walk-above simulation and calculated vertical times using standard geometry correction were done. The difference between the two scenarios was 6 ms one-way time (OWT) demonstrated the reduction of 6 ms uncertainty of using the advanced model-based correction versus the standard geometry correction. In short, the advanced technique delivered more reliable time-depth velocity information to reduce depth uncertainties for drilling operation.

The walk-above or vertical incidence checkshot survey, which required boat and navigation system, was unable to acquire in a highly deviated well due to very bad weather conditions. The rig-source survey was carried out instead of employing the walk-above survey in this project. The standard geometry correction using simple trigonometry was not able to provide the correct vertical times. The advanced model-based correction was the optimal solution to improve the accuracy of checkshot time-depth velocity data.
Drilling Performance Improvement Through use of Artificial Intelligence in Bit and Bottom Hole Assembly Selection in Gulf of Thailand
Authors: Tortrakul Nichnita , Pochan Chatwit , Southland Steve , Mala Pimjai , Pichaichanlert Tawpath , Tangsawanich Yuranan
Published: June 2021

This paper describes a method of transforming legacy manual bit/BHA planning process into a digital solution to enhance drilling assembly selection efficiency and consistency. The solution presented improves overall capital stewardship thru an effective and semi-automated use of data to deliver high quality decisions and improve decision consistency across drilling applications and drive drilling performance.

Data science and machine learning is applied to streamline the data preparation process and present to the user a statistically sound drilling assembly solution for the drilling environment input. A large +6000 well database is used to explore alternatives and rank potential solutions using performance and directional compatibility characteristics unique to the Gulf of Thailand.

The digital project goal presented is two-fold. The first is to streamline all related data and decision processes in the office to improve work efficiency and information accessibility. The second goal is to improve field drilling performance by installation of a self-learning advisory tool.

There is a requirement for multiple sub-processes to work in parallel. The population of data in the database and quality checks must be automated to handle hourly/daily data updates. A system for auto-loading drilling data from rigsite was created. A second system containing data science and machine learning was created to identify similar wells, rank their respective performance and directional compatibility to a future well of interest, and offer a statistically relevant solution recommendation.

A benefit of such a system is a more efficient workflow with improved field drilling results while effectively capturing Chevron Thailand methods for many drilling engineers to use in the future.

Adopting agile concept during development phase is one of the keys to success for this project. Additionally, utilization of digital transformation technology is a key enabler to handle big data, data science and data foundation.
Comparison of International Federation of cervical pathology and colposcopy nomenclature (2011) and Swede score for assessment of cervical lesions
Authors: Gupta Bindiya , Shreya Rashmi , Rajaram Shalini , Singla Anshuja , Jain Sandhya , Prasad Bhavya
Published: June 2021

Purpose: Standardization of colposcopic evaluation is important as it is observer dependent.The aim of the study was to compare the strength of association of colposcopic findings by International Federation of Colposcopy and Cervical Pathology (IFCPC) nomenclature and Swede score. Methods: In the prospective study, 150 women aged 30 to 60 years with abnormal screening results underwent colposcopy, the findings were evaluated using both IFCPC and Swede score and biopsy was taken from abnormal areas. Performances by both the methods were calculated taking biopsy as gold standard. Results: Nineteen ≥ CIN2 lesions were detected. The sensitivity, specificity, positive predictive value and negative predictive value for detecting ≥ CIN2 lesion by IFCPC scoring was 63.6%, 96.0%, 78.7%, 91.9%. Using Swede score, sensitivity, specificity, positive predictive value and negative predictive value at cut off of 8 were 42.4, 95%, 96.6% and 81.8% while at cut-off of 5, these were 96%, 88.3%,76.7% and 93.6%. The agreement between IFCPC major lesion and Swede score ≥ 8 for ≥ CIN2 was 0.626 (p<0.01). Conclusion: Swede score is an easier and more objective method for colposcopic evaluation and a score >8 can be applied to the screen and treat programme.
A morphological and molecular survey of Neoconidiobolus reveals a new species and two new combinations
Authors: Nie Yong , Wang Zi-Min , Liu Xiao-Yong , Huang Bo
Published: June 2021

The genus Neoconidiobolus was recently established to accommodate all members of the Conidiobolus subgenus Conidiobolus. Based on mitochondrial small subunit (mtSSU), nuclear large subunit (nucLSU) of rDNA and translation elongation factor 1-alpha (TEF1), this study further resolved the genus Neoconidiobolus into three clades, with three new taxa being added. They are N. kunyushanensis B. Huang & Y. Nie, sp. nov., N. lamprauges (Drechsler) B. Huang & Y. Nie, comb. nov., and N. nanodes (Drechsler) B. Huang & Y. Nie, comb. nov. Meanwhile, a morphologial comparison among species in the three clades and a key to the species of the genus Neoconidiobolus are provided herein.
Distribution of butyltin compounds in the coastal environment of the Bahía Blanca estuary, Argentina
Authors: Quintas Pamela Yanina , Arias Andrés , Álvarez Mónica , Domini Claudia , Garrido Mariano , Marcovecchio Jorge
Published: June 2021

This study evaluates for the first time the distribution and accumulation of butyltin compounds (BTs) in different compartments as seawater, sediments, suspended particulate matter (SPM) and mussels (Brachidontes rodriguezii) in the Bahía Blanca estuary. The samples were collected from six sampling sites with different anthropogenic impact. A better visualization and interpretation of data were achieved using chemometric tools (Tucker4 model), which made it possible to reveal the main relationships between the variables. This analysis showed the presence of BTs in all environmental compartments along the estuary, even in sites with low human intervention. The relationships found between BTs levels, seasons and environmental matrices show the importance of biological processes such as phytoplankton blooms and remobilization of sediments (by tidal dynamics and/or periodic dredging) in the BTs distribution and degradation. In addition, partition coefficients showed that mussels mainly bioaccumulate tributyltin through sediment, water and, to a lesser extent, from SPM.
Climate Change and Ecological Engineering Jointly Induced Vegetation Greening in Global Karst Regions From 2001 to 2020
Authors: Huang Jing , Ge Zhongxi , Huang Yuqing , Tang Xuguang , Shi Zhan , Lai Peiyu , Song Zengjing , Hao Binfei , Yang Hong , Ma Mingguo
Published: June 2021

Backgrounds

Vegetation dynamic plays a dominant role in the global carbon cycle and climate, especially in vulnerable karst ecosystem. Many studies have examined past several decades changes in vegetation greenness and the associated with climate drivers. Yet, few studies have analyzed the vegetation change in global karst regions particularly in the last decades when climate change and anthropogenic disturbance widely occurred.
Methods

In this study, we investigated the spatio-temporal variations of vegetation dynamic using the Seasonally Integrated Normalized Difference Vegetation Index (SINDVI) and examined their relationship to climate changes by correlation analysis, the ordinary least squares method investigate the variation trends and the Mann-Kendal test to detect the turning point from 2001 to 2020.
Results

As expected, there have greening trend in global karst SINDVI from 2001 to 2020, with significant increasing trend in China (range = 0.836, P < 0.05), Europe (range = 0.456, P < 0.05) and many other regions. According to correlation analyses, SINDVI is water-limited in arid and semi-arid regions, such as Middle East and central Asia, and temperature-limited in northern high-latitude.
Conclusions

consistent with previous studies, our results suggest that anthropogenic activities are mainly responsible for increasing vegetation greenness in tailoring management measures (e.g., Ecological Engineering, the Grain to Green Project) of China and Europe, intensive farmed in Middle East. Coupling warming temperature and increasing precipitation, southeastern Asia and Russia showed an increasing trend in SINDVI. In general, climate factors were the dominant drivers of the variation in vegetation greenness in globally karst regions during research period.
The role of Resveratrol, Sirtuin1 and RXRα as prognostic markers in ovarian cancer
Authors: Chen Fangfang , Kolben Thomas , Meister Sarah , Czogalla Bastian , Kolben Theresa M , Hester Anna , Burges Alexander , Trillsch Fabian , Schmoeckel Eisa , Mayr Doris , Mayerhofer Artur , Mahner Sven , Jeschke Udo , Beyer Susanne
Published: June 2021

Objective: Ovarian cancer is the most lethal gynecologic cancer. Resveratrol (RSV) is known to alter metabolism in cancer. It affects the nuclear retinoid-X-receptor (RXR), which implies a modulating effect of RXR to gynecologic cancers. Furthermore, RSV targets Sirtuin1 (Sirt1), a histone deacetylase. Study design: 123 tissue samples of patients with serous or mucinous ovarian cancer were examined for expression of Sirt1 and RXR. Ovarian cell-lines were treated with RSV and consequences on viability and apoptosis were evaluated. The influence of RSV to Sirt1 and RXR expression was analyzed by western blotting. Results: A correlation of nuclear Sirt1 and RXRα expression could be detected (p=0.006). Co-expression of nuclear RXRα and cytoplasmic (p=0.026) or nuclear (p=0.041) Sirt1 was associated with significantly increased overall survival in advanced tumor stages. Viability was decreased in all cell-lines after stimulation with resveratrol, while cell apoptosis was increased. RSV treatment led to significant lower Sirt1 expression in A2780 cells (p=0.025) and significant increased RXR expression in cisA2780 cells (p=0.012). Conclusion: In order to use RSV as medical target, studies could be developed to improve the understanding of drug resistance mechanisms and consequently improve treatment outcome.
Climate policy and wealth distribution
Authors: Thang Dao Nguyen
Published: June 2021

We set up a model with inter-generational bequest transfers and a climate damage on the wealth of heterogeneous households. We show that, under the imperfections of credit markets and depending on the wealth distribution across households, a balanced budget climate policy may widen the wealth inequality between the rich and the poor class. A climate policy may create positive effects on the wealth of households but these effects are asymmetric across households in terms of both magnitudes and the transmissions of the gains from climate policy within households. The poor's gains from the climate policy are mainly transmitted into improving the living standard and then to invest in human capital because of the higher marginal return to education investment. In contrary, the rich's gains from the climate policy are transmitted biasedly into physical capital accumulation and enhance their monopoly position in producing intermediate inputs. We show that, for any climate policy, there exists a corresponding threshold of aggregate physical capital. When the aggregate physical capital of the economy exceeds this threshold then the corresponding climate policy may widen the inter-generational bequest transfers among heterogeneous households, therefore, contributing enlarge the wealth gap between the rich and the poor class in the long run.
Forest Structure and Anthropogenic Disturbances Regulate Plant Invasion in Urban Forests
Authors: Aryal Prakash Chandra , Aryal Chandramani , Bhusal Kiran , Chapagain Devendra , Dhamala Man Kumar , Maharjan Sanu Raja , Chhetri Parveen K
Published: June 2021

Urban forest ecosystems, the structure and functions therein, are subjected to anthropogenic disturbances. Native and sensitive species from those forests might be lost due to such disturbances. At the same time, supplemented anthropogenic resources might create opportunities for exotic and invasive species. Although, invasive species are considered as one of the major threats to the urban biodiversity and ecosystems, the researches on invasion dynamics in the Himalayas have mostly focused on the impacts of invasion on forest structure and productivity. This study aims to understand the influence of forest structure and anthropogenic factors in invasion success that are poorly covered in the existing literature. We selected 11 urban forest patches for the study considering the presence-absence of selected invasive species and structural attributes. We used Principal Component Analysis (PCA) to reduce co-linearity in the covariates and generalized linear mixed effects model (GLMM) to identify the factors affecting the invasion success. We found that the structural attributes of the forests and anthropogenic disturbances regulated invasion success in urban forests. This implies that maintaining urban forest structural attributes, especially maintaining the stands with large-sized trees, are essential to regulate and control invasion in the context of urbanization.
Past and Present Subjective Wellbeing: The Role of Contrast and Memory
Authors: Kollamparambil Umakrishnan
Published: June 2021

This study is an attempt to analyse the interrelationships between current, past and expected future subjective wellbeing (SWB) through the intermediating role of memory using the National Income Dynamics Study panel dataset for South Africa. The contribution of this study is in exploring the role of contrast (inter-temporal and social) in determining; a) the current levels of SWB and, b) the drivers of recall bias; within a causal framework in the context of a country with low average SWB and high SWB inequality. The results indicate significant presence of hedonic adaptation and reveals past and future contrast as important correlates of current subjective wellbeing. In addition, a perceived improvement in current happiness from the past, is associated with higher levels of current SWB, highlighting the intermediating role of memory. Memory, however, is observed to be biased with only 42% accuracy. Higher levels of current subjective wellbeing are found to enhance the probability of correct recall of past. An overall improvement bias is evident among those in the lower segment of the SWB distribution. The results reinforce the hypothesized simultaneous relationships between current SWB, inter-temporal contrast, and recall behaviour. Further the differences in our findings from European studies emphasise the relevance of context in driving these relationships.
Effect of Copper pretreatment on optical and electrical properties of camphor based graphene by chemical vapour deposition
Authors: Chaliyawala Harsh , Narasimman R. , Pati Ranjan K. , Mukhopadhyay Indrajit , Ray Abhijit
Published: June 2021

Polycrystalline copper (Cu) foil is widely used as catalytic substrate for graphene growth in chemical vapor deposition (CVD) technique. The surface properties of the Cu foil strongly affect the growth behavior and final quality of CVD-grown graphene. The effect of pretreatment of Cu foil using four different solutions (acetone, acetic acid, HCl and HNO3) on the graphene growth held in atmospheric pressure CVD and its subsequent impact on electrical and optical properties are investigated. Natural camphor is used as the solid carbon precursor. The surface characteristics before and after the growth are studied using scanning electron microscopy and atomic force microscopy. The pretreatment conditions of Cu and the growth of graphene from camphor were correlated using Raman spectroscopy, optical and electrical characteristics. Our findings suggest that HCl pretreated Cu foil exhibited large-domain, uniform coverage of the transferred graphene with excellent optical (> 93% at 550 nm) and electrical properties (sheet resistance of 861 ± 40 ohm/sq), with promisingly low RMS value of roughness (38 nm). The pretreatment process improved the quality of graphene by removing the surface impurity particles and surface native oxides. A Schottky junction diode of graphene/n-silicon is fabricated by transferring the graphene to SiO2/Si substrate under dark and illuminated conditions is also demonstrated to establish its potential in micro- and opto-electronics.
Clinical Utility of Oral Management in Allogeneic Hematopoietic Stem Cell Transplantation Recipients: Microbiological Evidence Based on Molecular Analysis of Oral Bacteria
Authors: Kawajiri Jumpei , Nagata Kokoro , Nakamura Akiko , Fujieda Atsushi , Ino Kazuko , Nomura Jouji , Arai Naoya , Ohishi Kohshi , Katayama Naoyuki , Nakase Kazunori
Published: June 2021

Purpose: This study aimed to clarify the clinical utility of oral management to prevent bloodstream infections by oral bacteria microbiologically in patients undergoing allogeneic hematopoietic stem cell transplantation (ASCT). Methods: Ten consecutive patients with hematological malignancies undergoing ASCT were enrolled in this study. We implemented dental treatments before transplantation, if required, and carried out oral hygiene instructions and oral management every other day after transplantation. Molecular analysis of bacterial DNA for seven oral species using a polymerase chain reaction (PCR) assay was performed for oral samples and peripheral blood once a week for 3 weeks after transplantation. Results: Periodontitis was found in all 10 patients (mild grade in 3 and middle grade in 7) for whom basic periodontal therapy was conducted. Necessary dental procedures, including tooth extraction of the tooth were performed in 5 patients. After transplantation, oral mucositis occurred in 10 patients (grade 1 in 3, grade 2 in 2, and grade 3 in 5) for whom oral hygiene instruction and oral care were continued every other day. PCR-identified three to six bacterial species in oral samples from nine patients, but none in peripheral blood from any patient during the observation period. Conclusions: Oral management prevented blood stream infections by oral bacteria in ASCT recipients despite the existence of periodontitis or oral mucositis. Its utility was confirmed by microbiological evidence based on molecular data.
Neuroanatomical correlates of poststroke complex regional pain syndrome: A voxel-based lesion symptom- mapping study
Authors: Lee Jae-Ik , Kwon Soon-Woo , Lee Ahry , Tae Woo-suk , Pyun Sung-Bom
Published: June 2021

Complex regional pain syndrome (CRPS) is a common poststroke complication. However, the neural substrates associated with CRPS remain unclear. We investigated the neural correlates associated with poststroke CRPS using voxel-based lesion‒symptom mapping (VLSM) analysis. Among 145 patients with ischemic stroke, 35 were diagnosed with CRPS and categorized into the poststroke CRPS group, and the remaining 110 into the control group. We compared the clinical characteristics between the groups. VLSM analysis was performed to identify the brain region associated with the development of poststroke CRPS. It suggested that damage to the caudate nucleus head, putamen, and white matter complexes in the corona radiata were significantly associated with poststroke CRPS development. The clinical findings suggested that the poststroke CRPS group had lower muscle strength; lower scores on Fugl‒Meyer assessment, Manual Function Test, Mini-Mental Status Examination; and higher incidence of absent somatosensory evoked potentials in the median nerve than the control group. The head of the caudate nucleus, putamen, and white matter complexes in the corona radiata were associated with poststroke CRPS development in ischemic stroke patients. These results facilitate an understanding of poststroke CRPS pathophysiology. Monitoring patients with lesions in these structures may aid the prevention and early treatment of poststroke CRPS.
An Effective Linear Precoding Scheme to Resolve High PAPR and High OOBE Problems of OFDM systems
Authors: Kawasaki Hikaru , Matsumura Takeshi , Kojima Fumihide
Published: June 2021

In the fifth-generation of mobile communications, the use of orthogonal frequency-division multiplexing is agreed by the Third Partnership Project as it was in the fourth-generation. On the other hand, the major problems of its transmitted signals are high out-of-band emission (OOBE) that causes strong interference to adjacent frequency bands and high peak power characteristics that limit device costs and power savings. For future communications, this paper proposes an effective method to resolve the problems based on linear precoding with the theoretical analyses. Numerical experiments show that compared with the usual OFDM, the proposed method can achieve 25 dB lower OOBE, 2 dB lower peak power, no error rate degradation with a practical computational complexity simultaneously.
Bibliometric analysis of global research on white rot fungi biotechnology for environmental application
Authors: Xiao Pengfei , Wu Dedong , Wang Jianqiao
Published: June 2021

In recent years, white rot fungi (WRF) have received tremendous attention as a biotechnological tool for environmental pollution control. Although there are a large number of research articles and reviews concerning WRF biotechnology in environmental application, to our knowledge no bibliometric research of this topic has been published. This study used bibliometric method to evaluated 3962 related publications collected from Web of Science Core Collection database published between 2003 and 2020. The results indicated that China was the most productive country, while the USA is the most active country in international cooperation. The closest international collaborative networks were evidenced between the USA and China. Most authors tend to cooperate within a small group, which leads to the lack of effective cooperation among different groups. The most prominent journals in this field were “International Biodeterioration & Biodegradation” and “Bioresource Technology”, and “Biotechnology Applied Microbiology” was the most popular subject category. The analysis of high-frequency keywords revealed that “laccase”, “biodegradation”, “decolorization” and “Phanerochaete chrysosporium” were the most cited terms among all publications, and that the hottest topics focus on pretreatment of biomass waste by WRF, decolorization of dye wastewater by WRF, and bioremediation of polluted environment by WRF, etc. Finally, the frontier topics and active authors in this research field were identified using burst detection. This bibliometric study promoted the future cooperative research and knowledge exchange by visualizing the recent developments and future trends in WRF biotechnology for environmental applications.
Hybrid Decoder with an Adaptive Fuzzy Logic Filter for Single-User Millimeter Wave Systems Under Impulsive Noise
Authors: Mulla Mustafa , Rizaner Ahmet , Ulusoy Ali Hakan
Published: June 2021

The conventional millimeter wave systems are mostly designed to operate only for the Gaussian noise model. Although this model simplifies the noise removal problem, recent research findings state that a mixture noise model with additive impulsive noise is a more realistic approximation for millimeter wave channels. In this paper, we propose a novel approach to eliminate the impulsive noise effects on single-user millimeter wave massive multiple-input-multiple-output system using an adaptive fuzzy logic filter. Hence, a fuzzy median filter is applied to the system and it is aimed to minimize the effects of the impulsive noise by ordering samples based on fuzzy rank. Simulation results show that the proposed filter successfully eliminates the impulsive noise effects and achieves a better bit error rate and spectral efficiency performance than the competing methods in the literature while also working efficiently in Gaussian noise.
Pipe Break Rate Assessment While Considering Physical and Operational Factors: A Methodology Based on Global Positioning System and Data Driven Techniques
Authors: Amiri-Ardakani Yaser , Najafzadeh Mohammad
Published: June 2021

Deterioration of urban Water Distribution Networks (WDNs) is one of the primary cases of water supply losses, leading to the huge expenditures on the replacement and rehabilitation of elements WDNs. An accurate prediction of pipes failure rate play a substantial role in the management of WDNs. In this study, a field study was conducted to register pipes break and relevant causes in the WDN of Yazd City, Iran. In this way, 851 water pipes were incepted and localized by the Global Positioning System (GPS) apparatus. Then, 1033 failure cases were reported in the eight zones of under study WDN during March-December 2014. Pipes break rate (BRP) was calculated using the depth of pipe installation (hP), number of failure (NP), pressure of water pipes in operation (P), and age of pipe (AP). After completing a pipe break database, robust Artificial Intelligence models, namely Multivariate Adaptive Regression Spline (MARS), Gene-Expression Programming (GEP), and M5 Model Tree were employed to extract precise formulation for the pipes break rate estimation. Results of the proposed relationships demonstrated that MARS model with Coefficient of Correlation (R) of 0.981 and Root Mean Square Error (RMSE) of 0.544 provided more satisfying efficiency than M5 model (R = 0.888 and RMSE = 1.096). Furthermore, statistical results indicated that MARS and GEP models had comparatively at the same accuracy level. Explicit equations by AI models were satisfactorily comparable with those obtained by literature review in terms of various conditions: physical, operational, and environmental factors and complexity of AI models. Through a probabilistic framework for the pipes break rate, the results of first-order reliability analysis that MARS technique had highly satisfying performance when MARS-extracted-equation was assigned as a limit state function.
LCR and AFD of the Products of Nakagami-m and Nakagami-m Squared Random Variables: Application to Wireless Communications Through Relays
Authors: Stefanovic Caslav , Milovanovic Ivan , Stefanovic Mihajlo
Published: June 2021

The paper considers level crossing rate (LCR) and average fade du- ration (AFD) of the product of independent and identically distributed (i.i.d) Nakagami-m (NM) and double NM squared (also known as gamma-gamma) random variables (RVs). The derived statistical results are than related to the radio-frequency (RF) - free space optical (FSO), dual-hop (DH), amplify- and forward (AF) relaying system over non turbulent-induced-fading channels (nTIFCs) and turbulent-induced-fading channels (TIFCs). The obtained re- sults of DH-AF, RF-FSO system over TIFCs and nTIFCs are numerically evaluated and graphically presented for all system model parameters.
Development of mathematical model for multi-user coded-cooperation based cognitive radio system and its outage probability analysis
Authors: Singh Garima , Kaur Gurjit
Published: June 2021

In this paper, single and multi-user coded-cooperation based cognitive radio system is developed by designing its mathematical model where both source and relay will communicate to a single destination with the help of each other. Then all possible multi-user scenarios are developed and their end-to-end outage probability (Pout) is calculated for underlay mode of cognitive radio. The performance of the system is analyzed in the form of channel gain and interference temperature constraint for Rayleigh fading channel. The proposed system concludes that the coded cooperation with cognitive radio outperform the available techniques in the form of bandwidth, diversity, spectrum utilization efficiency and also improves the quality of communication. Furthermore, the theoretical analysis of the outage probability for both system models is validated by asymptotic analysis. The proposed system can set as a standard for all those cognitive radio applications which requires better spectrum efficiency even if there is a scarcity of multiple physical antennas.
A Non-Stationary and Probabilistic Approach for Drought Characterization Using Trivariate and Pairwise Copula Construction (PCC) Model
Authors: Dixit Soumyashree , Jayakumar K V
Published: June 2021

Under the variable climatic conditions, the conventional Standardized Precipitation Index (SPI) and Reconnaissance Drought Index (RDI) are inadequate for predicting extreme drought characteristics. So in the present study, two indices namely, Non-stationary Standardized Precipitation Index (NSPI) and Non-stationary Reconnaissance Drought Index (NRDI) are developed by fitting non-stationary gamma (for precipitation series) and lognormal (for initial values,δ0) distributions. The Generalized Additive Model in Location, Scale and Shape (GAMLSS) framework, with time varying location parameters considering the external covariates, is used to fit the non-stationary distributions. This includes various large scale climate indices namely Multivariate ENSO Index (MEI), Southern Oscillation Index (SOI), Sea Surface Temperature (SST), and Indian Ocean Dipole (IOD) as external covariates for the non-stationary drought assessment. The performances of stationary and non-stationary models are compared based on the Akaika Information Criterion (AIC). Additionally, the drought characteristics are evaluated using Run theory analysis for both stationary and non-stationary drought indices. The study also concentrated on the trivariate copula as well as the Pairwise Copula Construction (PCC) models to estimate the drought recurrence intervals. The comparison of two copula models revealed that the PCC model performed better than the trivariate Student’s t copula model. The recurrence intervals arrived at for the drought events are different for trivariate copula model and PCC model. The area taken for the study is the Upper and Lower sub basins of the Godavari River basin. This study shows that non-stationary drought indices will be helpful in the accurate estimate of the drought characteristics under the changing climatic scenario.
Flavonoids Modulate Bacterial Endophyte Communities of Ginkgo Biloba Leaves
Authors: Lei Fangying , Huang Haonan , Yang Qin , Fu Shaodong , Guo Xue , Zhang Shuangfei , Xiao Yunhua , Liu Xueduan , Yin Huaqun , Zou Kai , Liang Yili
Published: June 2021

Plant-specialized secondary metabolites have ecological functions in mediating interactions between plants and their entophytes. Here, we aimed to reveal the interaction between flavonoid synthesis and endophytic bacterial communities in wild Ginkgo trees spanning 100-800 years. We found that flavonoids including quercetin, kaempferol and isorhamnetin decreased while the microbial diversity in leaves increased with the age of sampled trees. Older trees had more unique genera and shifted their endophytic bacterial community structure. Also, Mantel tests and correlation analysis indicated a generally significant (p < 0.05) negative correlation between endophytic bacterial communities and flavonoids. Additionally, both deterministic and stochastic processes could play roles in the assembly of endophytic bacterial communities in Ginkgo trees with a progressive increase in stochastic processes as flavonoid concentrations decreased. This study provides a mechanistic understanding of how flavonoids modulate the endophytic microbial community assembly.
Grain Yield Gains and Associated Traits in Tropical X Temperate Maize Germplasm Under High and Low Plant Density
Authors: Ndou Vince , Gasura Edmore , Chivenge Pauline , Derera John
Published: June 2021

Development of ideal breeding and crop management strategies that can improve maize grain yield under tropical environments is crucial. In the temperate regions, such yield improvements were achieved through use of genotypes that adapt high plant population density stress. However, tropical germplasm has poor tolerance to high plant population density stress, and thus it should be improved by temperate maize. The aim of this study was to estimate the genetic gains and identify traits associated with such gains in stable and high yielding temperate x tropical hybrids under low and high plant population densities. A total of 200 hybrids derived from a line x tester mating design of tropical x temperate germplasm were developed. These hybrids were evaluated for grain yield and allied traits under varied plant population densities. High yielding and stable hybrids, such as 15XH214, 15XH215 and 15XH121 were resistant to lodging and had higher number of leaves above the cob. The high genetic gains of 26% and desirable stress tolerance indices of these hybrids made them better performers over check hybrids under high plant population density. At high plant population density yield was correlated to stem lodging and number of leaves above the cob. Future gains in grain yield of these hybrids derived from temperate x tropical maize germplasm can be achieved by exploiting indirect selection for resistance to stem lodging and increased number of leaves above the cob under high plant density conditions.
Artificial Neural Networks for Resources Optimization in Energetic Environment
Authors: D'Angelo Gianni , Palmieri Francesco , Robustelli Antonio
Published: June 2021

Resource Planning Optimization (RPO) is a common task that many companies need to face to obtain several benefits, like budget improvements and run-time analyses. It is often addressed by using several software products and tools, based on sophisticated mathematical artifacts. However, these tools are not able to provide a practical solution because they are often expensive and time-consuming. On the other hand, Artificial Intelligence-based approaches have been increasingly used in many industrial and scientific fields in last decades, and have demonstrated to be a valid alternative to the classical mathematical-based methods. For this purpose, the following paper aims to investigate the use of multiple Artificial Neural Networks (ANNs) for solving a RPO problem related to the scheduling of different Combined Heat & Power (CHP) generators. The experimental results, carried out by using data extracted by considering a real Microgrid system, have confirmed the effectiveness of the proposed approach. Additionally, we show that multiple neural networks achieve up to a 6% improvement in average accuracy over Naive Bayes classifier, up to a 12% over Multi-Layer Perceptron classifier and up to a 13% over state-of-the-art ANNs in the presence of unbalanced training dataset.
Accumulation and Translocation of Eight Trace Metals by the Different Tissues of Abelmoschus Esculentus Moench. Irrigated With Untreated Wastewater
Authors: Ahmed Dalia Abd El-Azeem , Galal Tarek M. , Al-Yasi Hatim M. , Hassan Loutfy M. , Slima Dalia Fahmy
Published: June 2021

Usage of wastewater to irrigate crops increases in Egypt and the whole world as a result of water shortage. This study is conducted to explore the potential of Abelmoschus esculentus Moench. (Okra plant) to accumulate and translocate eight trace metals: lead: Pb, cadmium: Cd, chromium: Cr, copper: Cu, iron: Fe, manganese: Mn, nickel: Ni and zinc: Zn in its different tissues due to irrigation with untreated industrial wastewater. It extended to assess the effect of the irrigation with wastewater on the growth parameters, nutrients, pigments and organic contents of the cultivated okra plants.Two studied sites at South of Cairo was conducted, the first site (29°42'31.17" N and 31°15'11.56" E); represented by five cultivated fields irrigated with Nile water (control) and the second site (29°42'37.87" N and 31°17'14.53" E); fields irrigated with effluent receive untreated industrial wastewater. Three composite soil and irrigated water samples were collected from each site. A significant decrease in nutrients: nitrogen (N), Potassium (K) and Phosphorous (P) in soil and Plants were resulted due to irrigation with wastewater. Also, there was a significant increase in trace metals concentration in both soil and plants irrigated with wastewater. A significant decrement in okra growth parameters and leaves photosynthetic pigments (chlorophyll a and b and carotenoids) due to irrigation with wastewater. Iron was the highest accumulated metal in the plant's fruits (edible part) irrigated with wastewater. Also, the concentration of Cd, Cu, Fe, Mn, Ni and Zn (42.57, 140,67, 2756.67, 1293.33, 1326.67 and 877.83 mg kg− 1, respectively) was in the phytotoxic range. Wastewater irrigated okras accumulate all of the studied trace metals in their roots (Bioaccumulation factor: BF > 1). In contrast, okra plants had no accumulated trace metals strategy in their shoot, as translocation factor values were less than one. Authors recommended avoiding consuming okra plants cultivated in fields irrigated with wastewater due to high trace metals concentration in their edible part.
PiRNA MW557525 Promotes the Vitality and Pluripotency of Piwil2-iCSCs by Regulating NOP56.
Authors: Zhang Zhaoxia , Wang Zhang , Tan Xiaojun , Jin Liming , Wang Zhaoying , Shen Lianju , Long Chunlan , Wei Guanghui , He Dawei
Published: June 2021

Objective Cancer stem cells (CSCs) play an important role in tumor development. Some studies have demonstrated that P-element–induced wimpy testis (Piwi)–interacting ribonucleic acids (piRNAs) participate in the progression of various cancers. However, the detailed function of piRNAs in CSCs requires further investigation. The aim of the present study was to investigate the effect of the uknown upregulated piRNA MW557525 and its predicted target gene nucleolar protein 56 (NOP56) inPiwi-like protein 2 (Piwil2)–induced CSCs (Piwil2-iCSCs).Methods We screened differential piRNAs of Piwil2-iCSCs using high-throughput sequencing (HTS). Target genes were predicted by the miRanda algorithm and subjected to Gene Ontology (GO) analysis. One of the differential piRNAs, MW557525, and its target gene NOP56 were transfected and silenced in Piwil2-iCSCs, respectively. Quantitative real-time polymerase chain reaction (qRT-PCR) was conducted to detect expression levels of piRNA MW557525 and NOP56 in Piwil2-iCSCs after transfection. We measured protein levels of NOP56 in different groups via Western blot (WB), verified interactions using a dual luciferase reporter assay (LRA) and investigated the effect of piRNA MW557525 and NOP56 on Piwil2-iCSC proliferation using a Cell Counting Kit-8 (CCK-8). In addition, we evaluated cell migratory and invasive abilities via transwell assay and detected cell apoptotic ability via flow cytometry (FCM) assay. Protein levels of Cluster of Differentiation 24 (CD24), CD133, Krüppel-like factor 4 (KLF4) and sex-determining region Y–related high-mobility group (HMG) box 12 (SOX2) were measured to evaluate the change in Piwil2-iCSC pluripotency after transfection.Results Via HTS, we screened out 204 differential piRNAs, and miRanda predicted 77 target genes. GO analysis showed that the biological processes (BPs) of these target genes were mainly involved in regulating the calcium concentration of cells and their molecular functions (MFs) were mainly involved in ATPase activity.The expression of piRNA MW557525 and NOP56 were significantly upregulated,and piRNA MW557525 was negatively associated with NOP56 in Piwil2-iCSCs. PiRNA MW557525 promoted proliferation, migration, invasion and pluripotency and inhibited apoptosis, while NOP56 suppressed proliferation, migration, invasion and pluripotency and induced apoptosis, in Piwil2-iCSCs.Conclusion Taken together, these findings suggested that piRNA MW557525 promoted and maintained the vitality and pluripotency of Piwil2-iCSCs, while NOP56 inhibited these characteristics. Therefore, piRNA MW557525 might be a novel therapeutic target in Piwil2-iCSCs.
Design and Simulation of High-performance Planar npp+ Heterojunction CH3NH3PbI3 Based Perovskite Solar Cells Using BaSnO3 ETM and Cu2O HTM
Authors: Rahman Atowar
Published: June 2021

In recent years, organic-inorganic hybrid perovskite solar cells (PSCs) have received more and more attention due to their high photovoltaic (PV) performance, potentially high efficiency, simple cost-effective, scalable, and vacuum-free fabrication techniques. Concerned, but there are still stability issues in PSCs. The use of inorganic materials as photogenerated carrier transport layers can enhance the stability of PSC. In this report, we designed a PSC model with a novel npp+ heterojunction cell structure of Al/ITO/BaSnO3 /CH3NH3 PbI3 /Cu2O/(Cu or Mo) and analyzed the structure by varying the thickness and carrier concentration of each constituent layer, working temperature, and back-contact metal work function using SCAPS-1D solar cell simulator. The simulation addresses, in particular, the role of the BaSnO3 as electron transport materials (ETM) and Cu2O as hole transport materials (HTM) for the device performance. Using BaSnO3 and Cu2O as ETM and HTM, respectively, this article presents the optimization of cell parameters to improve device performance with a predicted power conversion efficiency (PCE) of 32% for the modeled PSC. The proposed novel structure for PSC showed very good PV performance stability on elevated temperature with the temperature coefficient of PCE of only - 0.112 %K-1.
A Pilot Study on Educational Workshops for Caregivers of Patients with Brain Tumors Called AGAPE Showed its Feasibility and the Maintain Caregiver’s Quality of Life Despite Patient’s Disease Progression.
Authors: Bourien Héloïse , Pelotte Elodie , Thébault Aurélie , Larible-Lefort Claire , Lebrun Frédérique , Vauléon Elodie
Published: June 2021

Background

Several studies have highlighted the difficulties faced by caregivers of patients with brain tumors. We created the educational workshops called AGAPE. Their aim is to explain precisely the medical aspects of brain tumors, describe resources available, and allow a moment of exchange between caregivers.
Purpose
To evaluate outcomes of AGAPE.
Methods

This was an observational uncontrolled pilot study. Feasibility was evaluated by the caregivers’ attendance of the 2 theoretical scheduled sessions and their satisfaction. Additional outcomes were the percentage of caregivers in favour of AGAPE sustainability and the impact on their quality of life according to CarGOQoL questionnaires (Caregiver Oncology Quality of Life) between baseline before the first workshop and after the last one.
Results

From February 2015 to March 2019, 12 three-month sessions were organized allowing 87 caregivers to participate. 84% of caregivers attended at least 2 theoretical sessions, the level of satisfaction was very high, and all caregivers were in favor of AGAPE sustainability. 36 caregivers submitted completed questionnaires at baseline and after the last workshop attended, separated by more than 2 months. The first workshop took place mostly during or after the adjuvant treatment of their loved ones. Two-thirds of their loved ones had a progressive disease after the first workshop and 21 died. Caregivers’ quality of life was stable between the first and last attended workshop.
Conclusion

Our study showed that AGAPE helped to maintain caregiver’s quality of life despite patient’s disease progression and its feasibility. Moreover, AGAPE may easily be run in other hospitals.