bluuebunny/crossref_metadata_2025 huggingface dataset:
Flow Cytometric Methods for the Detection of Intracellular Signaling Proteins and Transcription Factors Reveal Heterogeneity in Differentiating Human B Cell Subsets
Authors: Marsman Casper , Jorritsma Tineke , ten Brinke Anja , van Ham Marieke
Published: December 2020

Flow cytometric detection of intracellular (IC) signaling proteins and transcription factors (TFs) will help elucidate the regulation of B cell survival, proliferation and differentiation. However, simultaneous detection of signaling proteins or TFs, with membrane markers (MM) can be challenging as required fixation and permeabilization procedures can affect functionality of conjugated antibodies. Here, a phosphoflow method is presented for detection of activated NF-κB p65 and phosphorylated STAT1, STAT3, STAT5 and STAT6 together with B cell differentiation MM CD19, CD27 and CD38. Additionally, a TF-flow method is presented that allows detection of B cell TFs; PAX5, c-MYC, BCL6, AID and antibody-secreting cell (ASC) TFs BLIMP1 and XBP-1s together with MM. Applying these methods on in vitro induced human B cell differentiation cultures showed significantly different steady-state levels, and responses to stimulation, of phosphorylated signaling proteins in CD27-expressing B cell and ASC populations. The TF-flow protocol and UMAP analysis revealed heterogeneity in TF-expression within stimulated CD27 or CD38-expressing B cell subsets. The methods presented here allow for sensitive analysis of STAT and NF-κB p65 signaling and TFs together with B cell differentiation MM at single-cell resolution. This will aid further investigation of B cell responses in both health and disease.
Connectivity and Savings Propensity among Odisha Tribals
Authors: Viswanath P.V.
Published: December 2020

Economic sustainability of rural areas is a concern given the increasing trend towards urbanization globally and in India. Self-reliant strategies, including increased savings and investment are more valuable in this regard than external interventions. This paper uses the results of a survey to examine the factors affecting saving in a rural part of Odisha populated primarily by tribals. Our tentative findings are that savings propensity is determined partly by the extent to which individuals feel connected to the broader economy, and partly by cultural factors. One implication of these findings is that connecting rural areas to other, possibly urban, locations could elicit greater saving and this could lead to greater development, employment possibilities, economic betterment and all the consequent social welfare implications. This paper relates savings propensity to new sociological population characteristics, such as perceived connectivity and food consumption patterns, and hence provides hitherto unexplored clues for policy initiatives to increase savings.
A Pre-aggregation Fuzzy Collaborative Intelligence-based Fuzzy Analytic Hierarchy Process Approach for Selecting Alternative Suppliers amid the COVID-19 Pandemic
Authors: Chen Toly , Wu Hsin-Chieh
Published: December 2020

In the existing group decision-making fuzzy analytic hierarchy process (FAHP) methods, the consensus among experts has rarely been fully reached. To fill this gap, in this study, a pre-aggregation fuzzy collaborative intelligence (FCI)-based FAHP approach is proposed. In the proposed pre-aggregation FCI-based FAHP approach, fuzzy intersection is applied to aggregate experts’ pairwise comparison results if these pairwise comparison results overlap. The aggregation result is a matrix of polygonal fuzzy numbers. Subsequently, alpha-cut operations are applied to derive the fuzzy priorities of criteria from the aggregation result. The pre-aggregation FCI-based FAHP approach has been applied to select suitable alternative suppliers for a wafer foundry in Taiwan amid the COVID-19 pandemic. The experimental results revealed that the pre-aggregation FCI-based FAHP approach significantly reduced the uncertainty inherent in the decision-making process by deriving fuzzy priorities with very narrow ranges.
Effect of Ethics Seminar on Moral Sensitivity and Ethical Behavior of Clinical Nurses
Authors: Lee Chunbok , Kim Sunman , Choe Kwisoon , Kim Sunghee
Published: December 2020

While nursing is an ethical profession, unethical behavior among nurses is increasing worldwide. This study examined the effects of an ethics seminar on nurses' moral sensitivity and ethical behavior. A total of 37 nurses (17 experimental, 20 control) were recruited. The ethics seminar was held over a 6-month period from May to October, 2018, and comprised six sessions held once a month for two hours. Moral sensitivity and unethical behavior were measured at the start and end of the seminar. Moral sensitivity and unethical behavior showed a negative correlation (r= -.455, p<0.01). After the ethics seminar, the experimental group's moral sensitivity was significantly increased (t = -1.039, p = 0.314). The mean scores of unethical behavior at pre and post-test in the experimental group were 12.59 and 9.47, respectively. This was a statistically significant difference (t = 3.118, p = 0.004). There was no statistically significant difference in the mean score in both moral sensitivity and unethical behavior in the control group. We conclude that ethics seminars can enhance moral sensitivity and reduce the risk of unethical behavior among nurses. Regular ethics seminars and training must be provided to nurses as a matter of policy.
Analisis potensi sabut kelapa serta strategi penggunaanya sebagai bahan baku pakan ternak ruminansia
Authors: Muzaki Mochamad Denta Risman , Sunarso Sunarso , Setiadi Agus
Published: December 2020

Tujuan: Tujuan dari penelitian mengkaji dan menganalisis potensi serta strategi penggunaan sabut kelapa sebagai bahan pakan pada complete feed dan konsentrat. Manfaat penelitian ini diharapkan dapat memberikan informasi kepada peternak atau perusahaan pakan ternak ruminansia dalam pemanfaatan limbah sabut kelapa sebagai campuran pada complete feed dan konsentrat. Lokasi penelitian berada di wilayah Kabupaten Batang, Kabupaten Jepara, Kabupaten Pati dan Kabupaten Rembang.

Metode: Metode yang digunakan dalam penelitian ini adalah metode survei. Data yang dikumpulkan berupa data primer didapat langsung dari petani kelapa, pedagang buah kelapa, setiap wilayah diambil sebanyak 10 responden. Data sekunder didapat dari Badan Pusat Statistik dan Dinas Perkebunan Kabupaten Batang, Kabupaten Jepara, Kabupaten Pati dan Kabupaten Rembang. Data yang sudah diperoleh diolah secara deskriptif analisis. Analisis Data menggunakan Analisis Locationt Quotient (LQ), Analisis SWOT dan Analisis Trend untuk memprediksi ketersediaan lahan dan produksi buah kelapa.

Hasil: Hasil dari penelitian menunjukkan bahwa penggunaan limbah sabut kelapa sebagai pakan memiliki potensi yang dapat dikembangkan menggunakan strategi (S-O), Strategi (S-T), Strategi (W-O) dan Srategi (W-T) pada analisis SWOT. Pengembangan lahan berdasarkan analisis Locationt Quotient (LQ) sebagai basis yaitu berada di Kabupaten Rembang, Pati dan Jepara. Produksi limbah sabut kelapa berdasarkan BK, PK dan TDN secara keseluruhan yaitu 9.537; 383.29 dan 2.678,4 ton/tahun dan untuk daya dukung limbah sabut kelapa secara keseluruhan berdasarkan BK, PK dan TDN yaitu 31.794; 944,32 dan 8.926 ST/tahun.
Kesimpulan: Kesimpulan dari penelitian yaitu peninjauan dalam produksi dan sediaan lahan dalam peningkatan tanaman kelapa menggunakan analisis Trend yang nantinya berpotensi menyediakan bahan baku yaitu berada pada Kabupaten Rembang.
Increasing Nurse Knowledge Using a Formal Lung Transplant Education Program
Authors: Stoddard Amy , Lynch-Smith Donna , Wrammert Kate Carlson , Bellflower Bobby
Published: December 2020

This quality improvement project was completed to show that a formal lung transplant education course for nurses caring for lung transplant patients increased their knowledge. An eight-hour education course was developed by experts in the field of lung transplantation. A pretest was administered before the education course. A posttest was administered to determine if knowledge was improved. A three-month follow-up test was administered to determine knowledge retention. Based on the data analysis, nurse knowledge improved after formal education. Item analysis determined what areas of educational content need to be the focus of quarterly education. The education course was adopted as formal training for transplant nurses.
PROBLEMS RELATED TO FIRST AID EQUIPMENT: ORGANIZATIONAL AND LEGAL ASPECT
Authors:   Federal Research Institute for Health Organization and Informatics of Ministry of Public Health of Russian Federation, Moscow, Dezhurny L.I. , Zakurdaeva A.Yu. ,   Federal Research Institute for Health Organization and Informatics of Ministry of Public Health of Russian Federation, Moscow
Published: December 2020

The article examines organizational and legal problems related to state registration, production, procurement and use of medical devices for first aid. The study significance is accounted for by the need to find solutions to problems related to equipping first aid activities with medical devices, which is becoming extremely important for the modern Russian society. Moreover, a comprehensive study of these issues has not been undertaken so far. The purpose of the study is to develop a set of proposals of an organizational and legal nature to improve quality of medical devices for first aid and equipping all potential participants of first aid delivery with such devices. To eliminate the problem of low equipment of potential participants of first aid delivery with the means of delivery, the composition of first-aid kits, packs, sets, and packages for all categories of participants have to be approval by the Ministry of Health of the Russian Federation. The authors also propose organizational and legal measures to improve interdepartmental and intradepartmental cooperation in this direction with the Russian Ministry of Health playing the coordinating role. The authors have also identified the need for improving the procedure for state registration of the production of first aid devices either though amending the Federal Law "On the Basics of Public Health Protection in the Russian Federation" regarding the provision that first-aid kits, packs, sets, and packages equipped with medical devices registered in the prescribed manner are not subject to state registration. As an alternative, the authors propose amendments and additions to the Rules of the state registration of medical devices, providing for a simplified state registration of first-aid kits, packs, sets, and packages. In addition, the authors name arguments in favor of improving the clinical trial procedure for first aid medical devices and propose changes to Article 38 of the Federal Law “On the Basics of Public Health Protection in the Russian Federation” in terms of eliminating the problems of legal techniques in the definition of the term “medical device” regarding first aid. Keywords: First aid; first aid kits; first aid equipment; medical devices.
CLUSTER ANALYSIS OF CIS COUNTRIES REGARDING DEVELOPMENT OF MEDICAL TOURISM IN KAZAKHSTAN
Authors:   Medical University of Karaganda, Kazakhstan, Baymenova A.S. , Zhakenova S.R. ,   Medical University of Karaganda, Kazakhstan, Аydaraliev A.A. ,   International University of Kyrgyzstan, Bishkek, Kyrgyzstan
Published: December 2020

Lack of highly qualified specialists or modern medical equipment, lack of financial resources, waiting in line in their own country encourages the majority of citizens to seek timely and high-quality medical care in another country. All conditions have been created in Kazakhstan to provide health care to foreign citizens. However, there are gaps in marketing strategies to promote medical tourism. The purpose of this study was to conduct a cluster analysis of the CIS countries on healthcare organization and morbidity for the subsequent determination of marketing policy to engage potential patients into medical tourism in Kazakhstan. Methods used: quantitative, qualitative and cluster analysis using Statistica v.8 software (StatSoftInc., USA). Because of unavailability of the necessary data, Uzbekistan and Turkmenistan were not included in the analysis. Since Kazakhstan is considered as a point of destination in this study, its indicators were excluded as well. The results of the study showed that within the CIS territory countries have different disease incidence rates regarding major classes of diseases, levels of healthcare organization, as well as significant differences in transport infrastructure, tourist services, information and communication technologies. This also plays an important role in shaping the marketing strategy of medical tourism. As a result of the analysis, 2 large and 4 small clusters of the CIS countries were developed. The formed clusters show similarities not only in healthcare, but also in cultural and racial characteristics. Each cluster was given a characteristic that, in current realities, can be used in targeted marketing tools. Thus, the obtained data can be used as one of the methods to eliminate major barriers slowing down the development of medical tourism, announced by the Concept for devloping medical tourism in Kazakhstan. Keywords: medical tourism; cluster analysis; export of medical services; CIS countries.
ОЦЕНКА ФАКТОРОВ, ВЛИЯЮЩИХ НА ЧАСТОТУ КОНТАКТОВ И ВТОРИЧНЫХ СЛУЧАЕВ COVID-19
Authors: Пшеничная Наталья , Лизинфельд Ирина , Журавлев Григорий
Published: December 2020

Резюме: Проведена оценка частоты контактов и вторичных случаев заболевания при различной локализации контактов с пациентами COVID-19. Оценка выполнена на основе отдельных данных мониторинга, проводимого Роспотребнадзором в январе–июне 2020. Полученные результаты демонстрируют высокий риск передачи инфекции в бытовых очагах во всех возрастных группах, что способствует распространению COVID-19 в популяции.
Association between Allelic Variations of -174G/C Polymorphism of Interleukin-6 Gene and Chronic Kidney Disease-Mineral and Bone Disorder in Iraqi Patients
Authors: Radeef Mohanad
Published: December 2020

This study designed to examine association between-174G/C polymorphism of interleukin-6 gene and phosphate, calcium, vitamin D3, and parathyroid hormone levels in Iraqi patient with chronic kidney disease on maintenance hemodialysis. Seventy chronic renal failure patients (patients group) and 20 healthy subjects (control group) were genotyped for interleukin-6 polymorphism and genotyping was performed by conventional polymerase chain reaction-restriction fragment length polymorphism. No significant differences in phosphate levels were observed in patients and control with different interleukin-6 genotypes. Control had non-significant differences in calcium levels, while patients with GG and CG genotypes displayed significant elevation with time. Conversely, control and patients with GG and CC genotypes had significant elevation in vitamin D3 levels with time. Regarding parathyroid hormone, control had non-significant differences, while patients with GG and CC genotypes displayed significant elevation with time.

Patients with GG genotype displayed significant changes in calcium, vitamin D3 and parathyroid hormone levels with time.
Partial Sums of Some Fractional Operators of Bounded Turning
Authors: Abdulnaby Zainab Esa
Published: December 2020

In this paper, several conditions are put in order to compose the sequence of partial sums ,  and  of the fractional operators of analytic univalent functions ,  and   of bounded turning which are bounded turning too.
Experimental Study on GPR Detection of Voids inside and behind Tunnel Linings
Authors: Qin Hui , Xie Xiongyao , Tang Yu , Wang Zhengzheng
Published: December 2020

Ground penetrating radar (GPR) is considered an effective tool to detect tunnel lining voids. In this paper, an experimental study was carried out using a physical tunnel lining model to evaluate the performances of different antenna frequencies. We built a 4.2 m–long, 4.2 m–wide, and 2.0 m–high experimental model to simulate the secondary lining, initial lining, and surrounding rock of a tunnel structure. In the model, we created four categories of voids, which are voids in secondary and initial linings, a delamination between the secondary and initial linings, a delamination between the initial lining and sand, and a void buried in the sand, to simulate real cases in tunnel engineering. The GPR wave velocities in the sand and concrete of the model were measured using the reflection method for the calibration of void depth. We employed a commercial GPR system equipped with antennae of different centre frequencies to detect the voids. GPR data were processed using a conventional data processing flow, and the performances of different frequencies were examined. The results show that the 1000 MHz centre frequency GPR is capable of characterizing shallow buried voids in the secondary lining but is not able to penetrate into the initial lining. The 250 MHz centre frequency GPR system is not advised to detect voids in or behind tunnel linings due to its low resolving power for voids of centimetre sizes. The 500 MHz centre frequency GPR system is optimal for void detection because it demonstrated a balanced performance of resolving ability and investigation depth. The findings of this work could be useful references for antenna selection and data processing in real GPR applications.
The Application of Ground-airborne TEM Systems for Underground Cavity Detection in China
Authors: Xue Guo-qiang , Li Xiu , Yu Sheng-bao , Chen Wei-ying , Ji Yan-ju
Published: December 2020

Ground-based, electrical-source, and UAV-borne receiver TEM configurations have previously been used to map mines in Jiangsu Province, China. In this study, the EM responses of air-filled mine tunnels were simulated by using a three-dimensional (3D) vector finite element method. A new apparent resistivity formula has been proposed for the ground-airborne TEM configuration. In the study area, field measurements were carried out along 36 profiles for the ground-airborne TEM and 16 profiles for ground TEM. The ground-airborne TEM results were determined to be in good agreement with the ground TEM survey results using a surface central loop, and were also consistent with the known geologic conditions. The experiment was successful and showed that a ground-ground-airborne TEM method could potentially become a novel alternative for both future civilian and military applications.

[Figure: see text]
Identifying Deep Saturated Coal Bed Zones in China through the Use of Large Loop TEM
Authors: Xue Guo-qiang , Chen Wei-ying , Ma Zhen-jun , Hou Dong-yang
Published: December 2020

Most of the shallow mineral deposits of China have already been mined because of the country's fast-growing social and economic development. Consequently, the exploration and mining of deep-seated coal deposits have become alternative ways to satisfy the energy needs for both domestic and industrial use. To ensure safe mining practices and avoid the intrusion of water from the bases of coal deposits, it has become essential to investigate the distribution of deep-seated coal deposits using appropriate and cost-effective geophysical methods. For example, a coal mine located in the southern part of China's Shanxi Province is characterized by a roof of dry rocks, whereas the coal beds in this area are saturated. A new technique which uses a large loop transient electromagnetic method (hereafter referred to as a modified central loop TEM) to detect geological targets located at deeper levels in the subsurface was successfully developed and applied in this study. The detection abilities of this technique, such as the time-domain responses and depth of investigation, as well as its sensitivity to deep targets, were analyzed. This new method was successfully employed to detect the floor of a 900 m deep coal seam at the location of the saturated coal beds in Shanxi Province. Wells were drilled to confirm the results, showing that the proposed method is both applicable and convenient for future exploration purposes. TEM could potentially be used to detect geological materials located at greater depths with higher detection accuracy.

[Figure: see text]
First Evidence of the Detection of an Underground Nuclear Magnetic Resonance Signal in a Tunnel
Authors: Lin Tingting , Yang Yujing , Yi Xiaofeng , Jiang Chuandong , Fan Tiehu
Published: December 2020

During the excavation of underground tunnels and ore mining, accidents related to sudden water inflows often occur. As the only technique used for the direct detection of groundwater, nuclear magnetic resonance (NMR) has advantages for the detection of disaster-inducing water flows. However, NMR has commonly been applied only at the ground surface using large-size loop with several turns (typically tens of meters). For the first time, we demonstrate that the water signal in a tunnel can be directly detected using an underground nuclear magnetic resonance (UNMR) experiment. Specifically, we describe the design of a six-meter multi-turn transmitting coil and receiving coil. By conducting UNMR measurements in the Dadushan Tunnel, located in southwestern China, we not only verified the ability to detect the UNMR signal, but also matched the observed data using a 1D inverse model.

[Figure: see text]
Joint Inversion of Seismic and Audio Magnetotelluric Data with Structural Constraint for Metallic Deposit
Authors: Feng Xuan , Nilot Enhedelihai , Liu Cai , Zhang Minghe , Yu Hailong , Zhao Jianyu , Sun Chengcheng
Published: December 2020

Audio magnetotelluric (AMT) and seismic methods are widely used to detect metallic deposits. However, each geophysical method only provides partial information of the underground target. Besides, individual methods have inherent limitations and ambiguity which leads to non-uniqueness when solving the inverse problem. To obtain a more robust and consistent ore deposit model, it is best to integrate different geophysical methods and data types. Towards this effort, we propose a joint inversion algorithm using cross-gradient constraint to build a connection between seismic and AMT data, and simultaneously invert for a resistivity and P-wave velocity model. Compared with separate AMT Gauss–Newton inversion and seismic Full waveform inversion (FWI) method, we can get more detailed and robust inversion results. In addition, frequency domain FWI with the Limited-Memory-Broyden–Fletcher–Goldfarb–Shanno (L-BFGS) algorithm provides an effective way to reduce computer memory usage and improve convergence speed. This joint inversion algorithm has been tested using simple synthetic models with two cross targets. The results obtained with separate inversions were compared with those obtained with joint inversion. Then, we applied the algorithm to geophysical models of the Jinchuan sulfide deposit. The AMT results obtained with joint inversion of seismic data were better than those obtained with separate AMT inversion. The joint inversion approach appears more robust than the traditional separate FWI inversion and it is recommended that the proposed algorithm be considered in future projects of real field data.
Data Analysis Protocol for Using Resistivity Array as an Early-Warning Wastewater Pond Leak Detector
Authors: Woodbury Bryan L. , Eigenberg Roger A. , Minns H. Gordon , Ndegwa Pius M.
Published: December 2020

Mineral and organic salts from beef manure in runoff alter the resistivity properties of soil and water. Typically, holding ponds are used to control runoff from concentrated animal feeding operations. The integrity of these holding ponds has come under increased scrutiny since subsurface leakage has the potential to affect soil and groundwater quality. Traditionally, leaks from holding ponds are detected by installing a series of monitoring wells at strategic locations near the pond to intercept any contaminants that reach groundwater. Monitoring wells are expensive to install, costly to sample, generate information that is difficult to interpret and can only warn of a leak after contamination of groundwater has already occurred. A method was developed to continually measure the soil quality around the perimeter of holding ponds. When a change is detected, a message can be sent to facility managers to alert them of potential problems. However, the analysis of the data generated by this new method can be difficult to interpret. A protocol was developed that has 1) a site-calibration method to tailor analysis for most geologic and geographic settings, 2) establishes statistical-based thresholds for detecting changes in soil and groundwater quality, 3) allows for detection sensitivity to be scaled, 4) provides a filter for reducing false-positive leak detections and 5) provides a consistent framework for regulatory reporting. The protocol is designed to be incorporated into automated software that can immediately notify pond managers of potential problems using currently available telecommunication technology.
Design of Analog Front-end Circuit for Audio-frequency Magnetotelluric Instrument
Authors: Zhang Yinglu , Xi Zhenzhu , Chen Xingpeng , Wei Honglan , Huang Long , Xiao Wei
Published: December 2020

High-performance audio-frequency magnetotelluric (AMT) instrument is one means of obtaining high-quality electromagnetic (EM) data. To improve the ability of AMT system to obtain high-quality data, this paper presents a design for a high-performance analog front-end circuit for AMT instrument. It mainly consists of the input protection, preamplifier, passive high pass filter, power frequency notch filter, programmable amplifier, and active low pass filter. In addition, this paper proposes a design of low-noise, high-performance preamplifier, which improves the common-mode rejection ratio (CMRR) of analog front-end circuit and effectively enhances the signal-to-noise ratio (SNR) of the circuit. The front-end circuit utilized two-stage twin-T notch filter to effectively suppress the strong interference of fundamental component of power frequency. Also, it used signal relays to control circuit gain and selection of cutoff frequency of anti-aliasing filter, resulting in the improvement of the capability of the analog-to-digital Converter (ADC) to distinguish weak EM signal.

The measured results of the electric field and magnetic field channel showed that: 1) The circuit works in frequency range of 1 Hz∼100 kHz; 2) The CMRR values of the preamplifier of electric field channel at low frequencies (1 Hz∼1 kHz) are 111 dB and 97 dB when the gains are 20 dB and 6 dB respectively; 3) The maximum attenuation fundamental power frequency can reach −39.46 dB and −39.04 dB respectively; 4) The total harmonic distortion rate at 1 kHz is 0.022% and 0.029% respectively; 5) The input noise levels of electric field channel are 12.67nV / [Formula: see text] @10Hz and 8.15V / [Formula: see text] @1kHz, while the input noise levels of magnetic field channel are 8.97nV / [Formula: see text] @10Hz and 6.16V / [Formula: see text] @1kHz; and 6) In conclusion, the analog front-end circuit is superior to meet the requirements of the AMT methods, and provides a useful reference for the development of AMT instrument.
Exploring the Japan Cave in Taman Hutan Raya Djuanda, Bandung Using GPR
Authors: Widodo Widodo , Azimmah Azizatun , Santoso Djoko
Published: December 2020

Investigating underground cavities is vital due to their potential for subsidence and total collapse. One of the proven geophysical methods for locating underground cavities at a shallow depth is ground penetrating radar (GPR). GPR uses contrasting dielectric permittivity, resistivity, and magnetic permeability to map the subsurface. The aim of this research is to prove that GPR can be applied to detect underground cavities in the Japan Cave of Taman Hutan Raya Djuanda, in Bandung, Indonesia. Forward modeling was performed first using three representative synthetic models before field data were acquired. The data acquisition was then conducted using a 100 MHz GPR shielded antenna with three lines of 80 m and one additional line 10 m long. The result showed a region of different reflection amplitude, which was proven to be the air-filled cavities.
Automated Data Extraction from Synthetic and Real Radargrams of Complex Structures
Authors: Bugarinović Željko , Meschino Simone , Vrtunski Milan , Pajewski Lara , Ristić Aleksandar , Derobert Xavier , Govedarica Miro
Published: December 2020

This paper presents a comparative study of two algorithms for detecting and analyzing the characteristic shapes of reflection obtained as a result of Ground-Penetrating Radar (GPR) scanning technology. The first algorithm is a sub-array processing method that uses direction-of-arrival algorithms and the matched filter technique; this approach is implemented in SPOT-GPR (release 1.0), a new freeware tool for the detection and localization of targets in radargrams. The second algorithm, APEX, is based on machine learning and pattern recognition techniques and it allows finding the coordinates of apexes and further characteristic points of hyperbolas in radargrams. Both software solutions are implemented in MATLAB environment. As a first step, we compare the accuracy of our algorithms when applied to synthetic data, calculated by using the open-source finite-difference time-domain simulator gprMax; the scenarios are two concrete cells hosting different metallic and dielectric targets. Then, we compare the accuracy of our algorithms when applied to experimental data, recorded over district heating pipes in a trench, with known geometry and depth of the pipes. For the latter scenario, we have also generated a gprMax radargram, matching the geometry and scanning settings of the real one; both algorithms are tested on this synthetic radargram, as well. Overall, both algorithms perform well and rather uniformly in localizing the targets. The accuracy of the algorithms is at centimeter level, which is sufficient in most applications.
Application of Cross-borehole Integrated Geophysical Methods for the Detailed Investigation of Karst in Urban Metro Construction
Authors: Zhang Jun , Liu Shengdong , Chen Qinghua , Wang Bo , Ren Chuan
Published: December 2020

With the significant development of China's metro construction, the development of urban underground karst poses a serious threat to related tunnel construction and public safety, with frequent occurrences of mud and water inrushes during tunnel construction and urban ground subsidence events. Because of the complex, urban, and shallow geological conditions and construction environments, conventional geophysical methods cannot meet the requirements for high-precision detection of small-scale and inhomogeneous complex geological bodies. Based on numerical simulation, herein we comprehensively applied both cross-borehole electrical resistivity tomography (ERT) and cross-borehole seismic computed tomography (CT) to urban underground karst surveys of the Hangzhou-Fuyang intercity railway. The results showed that: 1) under limited urban construction conditions, the use of advanced geophysical monitoring equipment greatly improved construction efficiency; 2) utilizing drilling geological results to calibrate the abnormal geophysical field attribute parameters (including wave velocity and resistivity) improved the accuracy of karst exploration and reduce defective geophysical multi-explanation effects; 3) applying the joint comparative explanation of both velocity and resistivity profiles can distinguish and explain karst and fracture development zones; 4) 550 pairs of velocity and resistivity profiles were obtained which revealed 258 karst cave anomalies and 5 fracture development zones which integrated detection accuracy exceeded the 1 m level. Thus, the high-precision joint cross-borehole tomography technology was shown to be useful for guiding intercity railway construction.
Application of the Fisher Optimal Segmentation Method in MT Interpretation: A Case Study from Qiangtang Basin, Qinghai -Tibet Plateau
Authors: Zhu Chuanqing , Yang Shujiang , Zhao Huixia , Wang Caifu , Lin Cunguo , Jiang Zhongcheng , Luo Xinqing
Published: December 2020

The development and construction of thrust faults in mountain front areas are quite complicated, causing interpretation difficulties with electrical resistivity. To address these difficulties, an optimal stratification method involving magnetotellurics (MT) was applied, based on Fisher's clustering method for continuous data. The feasibility and effectiveness of this method are verified by applying it to the MT exploration data in Qiangtang Basin, Qinghai-Tibet Plateau, China. The results show that the optimal stratification method can improve the resolution of the resistivity model effectively in areas with complex structures. The MT inversion section after optimal stratification reflects the stratum interface, fault and structure style more directly and can be used for comparison with seismic data. The Fisher segmentation method can be applied to the interpretation of the MT data as a supplementary method, especially in the complicated structural belts, areas in which the geological structure and deformation information cannot be recognized effectively by conventional methods.
Evaluation of Unknown Bridge Foundations Using Borehole-based Nondestructive Testing Methods: A Case Study in Urban Settings
Authors: Coe Joseph Thomas , Kermani Behnoud , Nyquist Jonathan
Published: December 2020

There are a significant number of bridges for which information regarding the foundation is missing or incomplete. It is extremely challenging to evaluate the performance of such unknown foundation bridges (UFB), particularly against scour or when their foundations are reused. For critical UFB, it is often necessary to estimate performance by developing an appropriate working model of subsurface foundation conditions. Typically, nondestructive testing (NDT) has served as the most viable alternative due to the costs and risk associated with excavation, coring, and probing. NDT can be quite difficult to perform and their results can contain significant uncertainty in highly urban settings. The primary objective of this study was therefore to compare performance of borehole NDT methods when evaluating the depth of two in-service unknown foundations (concrete-filled steel pipe piles and H-piles) in highly urban settings. The borehole magnetic, parallel seismic, borehole sonic, and borehole radar methods were implemented to determine the foundation bottom locations. Though uncertainty was present in all measurements, the borehole magnetometer and radar results proved the most conclusive. Parallel seismic testing did not yield any evidence of foundations due to issues with background noise and lack of direct access to the foundation. Likewise, borehole sonic testing was generally inconclusive due to issues with sensor directivity and attenuation. Borehole magnetometer estimated the depth to the foundation bottom as 8.6 m and 9.2 m at the two sites. Borehole radar estimates for the depth to foundation bottom compared favorably at 9.8 m and 8.0 m for the two sites. Given the borehole construction and depth to competent rock at the sites, these results for borehole magnetometer and radar were likely a minimum estimate for the location of the foundation bottoms. Such information can help evaluate long-term performance of this system as part of rehabilitation and reuse efforts.
OMWS Method for Weak Signal Processing of GPR and Its Application in the Identification of Concrete Microcracks
Authors: Ling Tonghua , Zhang Liang , Liu Haoran , Gu Danping , Yu Bin , Zhang Sheng
Published: December 2020

To reduce the impact of attenuation and dispersion in ground penetrating radar (GPR) detection and to effectively improve GPR profile recording and to identify a weak detection target, a high-resolution processing method based on orthogonal matching pursuit and wavelet spectrum whitening (the OMWS method) is presented. First, according to the matching pursuit algorithm and the strong reflection-forming mechanism and based on sparse representation theory, a sparse dictionary suitable for the characteristics of a strong reflection signal was selected, and the signal was decomposed, which displayed the weak target signal well. Second, wavelet analysis was used to decompose the processed GPR signal into time-domain subsignals in different frequency bands, and each subsignal was whitened by a whitening filter. Then, the processed subsignals were reconstructed. The final results were compared with the results of conventional spectrum whitening method and showed that the OMWS method can accurately weaken the effect of the strong impedance interface and effectively enhance the local information of microcrack-reflected signals in both the time and frequency domains. The resolution of the processed GPR image is greatly improved, and the reflected signal of the hidden microcrack is easily visible. The method is clearer and more intuitive in the expression of the weak signals of hidden microcrack than the conventional spectrum whitening method, and the compensation for the high-frequency of the signals is more obvious.
Gaussian Processes for Hydrocarbon Depth Estimation in Forward Modeling of Seabed Logging
Authors: Aris Muhammad Naeim Mohd , Daud Hanita , Dass Sarat Chandra , Noh Khairul Arifin Mohd
Published: December 2020

Seabed logging (SBL) is an application of the marine controlled-source electromagnetic (CSEM) technique to discover offshore hydrocarbon reservoirs underneath the seabed. This application is based on electrical resistivity contrast between hydrocarbon and its surroundings. In this paper, simulation and forward modeling were performed to estimate the hydrocarbon depths in one-dimensional (1-D) SBL data. 1-D data, consisted offset distance (input) and magnitude of electric field (output), were acquired from SBL models developed using computer simulation technology (CST) software. The computer simulated outputs were observed at various depths of hydrocarbon reservoir (250 m–2,750 m with an increment of 250 m) with frequency of 0.125 Hz. Gaussian processes (GP) was employed in the forward modeling by utilizing prior information which is electric field (E-field) at all observed inputs to provide E-field profile at unobserved/untried inputs with uncertainty quantification in terms of variance. The concept was extended for two-dimensional (2-D) model. All observations of E-field were then investigated with the 2-D forward GP model. Root mean square error (RMSE) and coefficient of variation (CV) were utilized to compare the acquired and modeled data at random untried hydrocarbon depths at 400 m, 950 m, 1,450 m, 2,100 m and 2,600 m. Small RMSE and CV values have indicated that developed model can fit well the SBL data at untried hydrocarbon depths. The measured variances of the untried inputs revealed that the data points (true values) were very close to the estimated values, which was 0.003 (in average). RMSEs obtained were very small as an average of 0.049, and CVs found as very reliable percentages, an average of 0.914%, which implied well fitting of the GP model. Hence, the 2-D forward GP model is believed to be capable of predicting unobserved hydrocarbon depths.
Geophysical Interpretation of a Subsurface Landslide in the Southern Qinshui Basin
Authors: Chen Qiang , Zhang Sheng , Chang Suoliang , Liu Bo , Liu Jun , Long Jianhui
Published: December 2020

A subsurface landslide is the key problem to a large affordable home program in the southern Qinshui Basin, China. A geophysical survey integrated with seismic refraction tomography (SRT), seismic scattered wave imaging (SSI), and electrical resistivity tomography (ERT) was performed along five profiles over the landslide body. The bedrock surface was a crucial interface, represented by a relatively high velocity, high density, and high resistivity in contrast to the unconsolidated soil and landslide material above it. Based on the most comparable geophysical features, several problems were uncovered such as a “sandwich velocity structure” in the SRT results, velocity trap in the SSI results, and rapid variations in the local topography in all three methods. Aiming to improve the comprehensive interpretation of the ERT, SRT, SSI data, the vertical gradient extremum in the ERT and SRT data and tracing the target wave group according to the velocity sensitivity in the SSI data were analyzed. Moreover, a joint interpretation of the three geophysical survey datasets as well as 32 geological wells and 73 geotechnical boreholes helped to determine one undulating bedrock surface, delineate two types of failure surface geometry (landslide surface and collapse surface), and identify three external shapes in the ex situ body (ancient river channel, landslide body and collapse body). The results showed that the integrated geophysical survey not only provided detailed evidence for the existing of landslide but also presented meaningful evidence for the sliding mechanism. These results were difficult to fully describe and to apply to understanding landslide processes. Furthermore, for near-surface landslide events, the joint interpretation of geologic, geotechnical and geophysical data was necessary to reduce problems with any single geophysical survey.
Using Geophysics to Investigate Texture and Salinity of Agricultural Soils and Their Impact on Crop Growth in El Paso County, Texas
Authors: Doser Diane I. , Ornelas Marc A. , Martinez Isaac , Jin Lixin , Ortiz Anna , Kaip Galen M.
Published: December 2020

Soil properties within the Rio Grande valley near El Paso are strongly linked to the types of fluvial deposits that serve as parent material. We used four geophysical techniques (DC resistivity, ground conductivity, capacitively coupled resistivity and magnetics) to distinguish between soil units in an alfalfa field. We combined these observations with geochemical characterization and particle size analysis in order to determine how these soils and irrigation practices influence salt buildup and water availability, and thus crop growth. Soils mapped at the site were derived from crevasse splay and flood plain deposits. Results of our investigation showed that the alfalfa grew better in soils with a 1.25 m thick unit of 40-70% sand that fined into a silty-clay (<20% sand) at greater depths. Poorer growth occurred in soils where a 0.8 m thick silty-clay (<20% sand) was underlain by a less than 2 m thick sand unit (>90% sand) we interpret as an abandoned river channel. The DC resistivity, capacitively coupled resistivity and conductivity surveys were all responsive to the major grain size changes in the upper 3 meters of soil and were able to distinguish the buried river channel. The magnetics survey was not as successful at detecting the channel, but was able to characterize near-surface grain size variability and hence distinguish between the major soil units found at the site. We believe that similar geophysical techniques could be used to rapidly evaluate soil characteristics in other regions where soils are derived from fluvial parent material.
Unplugging Standalone Sand-Control Screens Using High-Power Shock Waves
Authors: Habibi Ali , Fensky Charles E. , Perri Mike , Roostaei Morteza , Mahmoudi Mahdi , Fattahpour Vahidoddin , Zeng Hongbo , Sadrzadeh Mohtada
Published: December 2020

Previous studies showed that different parameters influence the plugging of completion tools. These parameters include rock mineralogy, reservoir-fluid properties, and type of completion tools. Although different methods have been used for unplugging these tools, there is still debate regarding the performance of these methods on damage removal. In this study, we assessed the performance of high-power shock waves generated from an electrohydraulic-stimulation (EHS) tool on cleaning completion tools plugged during oil production. These devices were extracted from different wells in Canada, Europe, and the US. First, we quantified the extent of cleaning for the plugged slotted liners using the EHS tool at the laboratory scale. Next, we analyzed the mineral composition of the plugging materials removed after the treatment by conducting scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS), inductively coupled plasma mass spectroscopy (ICP-MS), colorimetric, and dry-combustion analyses. Finally, we reviewed the pulsing-stimulation-treatment results applied to several field case studies. The results of unplugging slotted liners at the laboratory scale showed that up to 28.5% of the plugged slots are cleaned after 120 pulses of shock waves. The mineral-characterization results showed that the main plugging materials are calcite, silicates, and iron-based components (corrosion products). The cleaning performance (CP) of the EHS tool increases by increasing the number of pulses and the output energy (OE) applied to the tool. The CP parameter is high at (i) high concentrations of carbonates, barium (Ba)-based components, and organic matter, and (ii) low concentrations of corrosion products and sulfates. The results of field case studies showed that the cleaning of the EHS tool is not limited to the sand-control devices and it can clean other tools that are less accessible for other techniques, such as subsurface safety valves. This paper provides a better understanding of the performance of shock waves on damage removal from plugged completion tools. The results could open new insight into the applications of shock waves for cleaning the completion tools.
Characteristics of retinal detachment associated with atopic dermatitis
Authors: Lee Youlim , Park Woo-kyung , Kim Rae-Young , Kim Mirinae , Park Young-Gun , Park Young-Hoon
Published: December 2020

Purpose: To examine the characteristics of rhegmatous retinal detachment(RRD) associated with atopic dermatitis.Study design: retrospective case-control studyMethodThe study was conducted between 2008 and 2018, whereby 2257 patients underwent RD surgery at this clinic. Among them, 61 patients who have been diagnosed as atopy were treated as experimental group, and 100 patients who didn’t have atopy were randomly selected as control group. MAIN OUTCOME MEASURES: In this study, demographics, characteristics of detachment, initial operative method, and prognosis after surgery were investigated. Additionally, in pseudophakic RD patients, the period between the cataract surgery and onset of RD was measured.Result: In atopy group, postoperative VA and prognosis were significantly worse and bilateral involvement of RD was more common than control group. However, it is notable that there was no difference of mean preoperative VA and refractive index between two groups. There was a difference in characteristics of retinal breaks in two groups. Additionally, it was noted that in pseudophakic patients, the risk of developing RD within 1 year after cataract surgery was significantly higher in atopic group than in control group.Conclusion: Generally speaking, RD in atopy occurs at a young age and has different characteristics noted than with non-atopic patients. In this context, atopic RD has poor visual prognosis, and for this reason it requires careful management. Furthermore, the risk of developing RD within 1 year after cataract surgery is higher in atopy, and thus we suggest regular and extensive check-up after cataract surgery especially in atopic patients.