bluuebunny/crossref_metadata_2025 huggingface dataset:
NESS2.0: An Updated Version of the Worldwide Dataset for Calibrating and Adjusting Ground-Motion Models in Near Source
Authors: Sgobba Sara , Felicetta Chiara , Lanzano Giovanni , Ramadan Fadel , D’Amico Maria , Pacor Francesca
Published: June 2021

We present an extended and updated version of the worldwide NEar-Source Strong-motion (NESS) flat file, which includes an increased number of moderate-to-strong earthquakes recorded in epicentral area, new source metadata and intensity measures, comprising spectral displacements and fling-step amplitudes retrieved from the extended baseline correction processing of velocity time series. The resulting dataset consists of 81 events with moment magnitude≥5.5 and hypocentral depth shallower than 40 km, corresponding to 1189 three-component waveforms, which are selected to have a maximum source-to-site distance within one fault length. Details on the flat files, metadata, and ground-motion parameters, processing scheme, and statistical findings are presented and discussed. The analysis of these data allows recognizing the presence of distinctive features (such as pulse-like waveforms, large vertical components, and hanging-wall effects) that can be exploited to assess their impact on near-source seismic motion. As an example, we use the NESS2.0 dataset for calibrating an empirical correction factor of a regional ground-motion model (GMM) mainly based on far-field records. In this way, we can adjust the median predictions to account for near-source effects not fully captured by the reference model. The final goal of this work is to promote the use of the NESS2 flat file as a tool to disseminate qualified and referenced near-source data and metadata in the light of improving the constraints of GMMs (both empirical and physics-based) close to the source.
Subsurface Characterization of the Quaternary Active Cheraw Fault in Southeastern Colorado Based on Seismic Imaging
Authors: Zellman Mark S. , Ostenaa Dean A. , Brown Morgan P.
Published: June 2021

The subsurface structure of the late Quaternary active Cheraw fault is relatively unstudied. Vertical displacement estimates of faulted bedrock horizons, characteristics of bedrock structure (e.g., dip), potential association with dissolution of underlying Permian evaporite strata, and whether or not a postulated northeast extension of the topographic scarp is associated with Quaternary faulting have remained open questions. In this study, we assess six 2D seismic reflection profiles that cross the Cheraw fault scarp, demonstrate how Quaternary normal faulting has reactivated pre-existing structures along the northwest flank of the Las Animas arch, and provide new constraints for seismic hazard characterization. We map the fault to depths of at least 1.5–1.8 km into lower Paleozoic strata in which the continuity of the fault through Permian evaporite indicates that dissolution of those stratigraphic intervals has no role in Quaternary surface faulting. Interpretation of the seismic data reveals an ∼75°±5° northwest-dipping fault with ∼24–30  m vertical displacement of upper Cretaceous strata, which coincides with Quaternary scarps at the surface.
Preliminary analysis of meteorological and seasonal influences on crustal gas emission relevant to earthquake prediction
Authors: Klusman Ronald W. , Webster James D.
Published: June 2021

abstract

The emission of gas from the Earth's crust is a complex process influenced by meteorological and seasonal parameters. The use of gas emission as a tool in earthquake prediction will require an understanding of these influences. Radon emanation has been integrated over weekly intervals and free mercury vapor emission over 212 hour intervals at a low seismic risk site in Colorado.

Radon measured by the Track Etch® technique ranged from 136 to 1750 tracks/mm2 (81 to 1040 pC/liter) over the 1-yr period of the experiment. There was a strong correlation of radon emanation with: instrument vault temperature, barometric pressure, outside temperature, soil temperature, and whether or not the surface soil was frozen. Seasonal influences on radon emanation are important with 94 per cent of the variance being accounted for by the measured meteorological and seasonal parameters.

Mercury concentrations in the instrument vault ranged from <1 to 53 ng/m3 over the 1 yr. Mercury emission correlates with vault temperature, vault relative humidity, outside temperature, barometric pressure, soil temperature and moisture, and the soil freeze-thaw cycle. Diurnal cycles are common but do not occur on all days. Other short-term noise in mercury emission is also important and phase shift or phase lag effects are important. Only 32 per cent of the variance in mercury emission can be accounted for by the measured meteorological and seasonal parameters. The short-term noise coupled with phase lags are important factors in mercury emission rates.
Effects of temporal variations in seismicity on seismic hazard
Authors: McGuire Robin K. , Barnhard Theodore P.
Published: June 2021

abstract

The accuracy of stationary mathematical models of seismicity for calculating probabilities of damaging shaking is examined using the history of earthquakes in China from 1350 A.D. to 1949 A.D. During this time, rates of seismic activity varied periodically by a factor of 10. Probabilities of damaging shaking are calculated in 62 cities in North China using 50 yr of earthquake data to estimate seismicity parameters; the probabilities are compared to statistics of damaging shaking in the same cities for 50 yr following the data window. These comparisons indicate that the seismic hazard analysis is accurate if: (1) the maximum possible earthquake size in each seismogenic zone is determined from the entire seismic history rather than from a short-time window; and (2) the future seismic activity can be estimated accurately. The first condition emphasizes the importance of realistically estimating the maximum possible size of earthquakes on faults. The second indicates the need to understand possible trends in seismic activity where these exist, or to develop an earthquake prediction capability with which to estimate future activity. Without the capability of estimating future seismicity, stationary models provide less accurate but generally conservative indications of seismic ground-shaking hazard.

In the United States, the available earthquake history is brief but gives no indication of changing rates of activity. The rate of seismic strain release in the Central and Eastern United States has been constant over the last 180 yr, and the geological record of earthquakes on the southern San Andreas Fault indicates no temporal trend for large shocks over the last 15 centuries. Both observations imply that seismic activity is either stationary or of such a long period that it may be treated as stationary for seismic hazard analyses in the United States.
P-wave spectra forML5 foreshocks, aftershocks, and isolated earthquakes near Parkfield, California
Authors: Bakun Willian H. , McEvilly Thomas V.
Published: June 2021

abstract

Wood-Anderson seismograms recorded at Mount Hamilton (MHC, 185 km, 327°), Santa Barbara (SBC, 180 km, 158°), and Tinemaha (TIN, 240 km, 56°) provide data for comparing P-wave spectra for two immediate (17-min) foreshocks, one early (55-hr) foreshock, two aftershocks, and two “isolated” Parkfield earthquakes. All are ML 5.0 shocks with epicenters within 7 km of the common epicenter of the 1934 and 1966 Parkfield main shocks. The set of events is well suited for testing the hypothesis that foreshocks are high-stress-drop sources. Calculated stress drops are controlled by source directivity at azimuths aligned with the fault break (at MHC and SBC). P-wave radiation from the three foreshocks is focused along one fault trace azimuth, suggesting that foreshock sources are characterized by pronounced unilateral rupture expansion. At TIN, broadside to the fault where directivity has minimum effect on calculated relative stress drop, the two immediate foreshocks are higher stress-drop sources. The early foreshock is a low-to-average stress-drop source, indicating the possibility that stress concentration is a rapidly occurring phenomenon in rupture nucleation. Alternatively, the stress field is highly variable on the scale of 2 to 3 km in the focal region of an impending earthquake with a rupture length of 20 to 30 km.
The purpose and effects of earthquake codes
Authors: Zsutty Theodore C. , Shah Haresh C.
Published: June 2021

abstract

When large earthquakes occur and there is significant damage and destruction of building structures, an almost universal response is the demand for better (and usually bigger) building codes. This paper examines the effects of this public outcry for protection with respect to the economic consequences, the actual process of seismic code formulation, and the technical adequacy of our present knowledge and design procedures. Some general directions are suggested such that new codes can be: better understood with respect to their intended design objectives; economically feasible; and practically enforceable.
Dynamic inelastic analyses of a bridge structure
Authors: Gillies A. G. , Shepherd R.
Published: June 2021

abstract

The necessity for framed structures to be capable of dissipating significant amounts of energy inelastically under severe earthquake excitation is generally acknowledged. Bridge structures differ from buildings in their seismic lateral resistance mechanism in so far as they generally possess a small number of clearly identifiable potential zones in which plastic yield can occur and consequently tend to be amenable to postelastic studies. This paper presents the application of an analysis technique in which the response time history of a bridge structure, treated as a three-dimensional frame, is determined by direct integration of the equations of motion with allowances incorporated for inelastic member behavior. Aspects studied include the differences in responses predicted using a nonlinear three-dimensional model rather than a planar frame idealization and the effect of unequal span lengths or torsional vibrations.
Effects of fault finiteness on near-source ground motion
Authors: Archuleta Ralph J. , Hartzell Stephen H.
Published: June 2021

abstract

Near-source ground motion at four azimuths but constant epicentral range is computed from a buried circular strike-slip fault in a half-space. Particle acceleration, velocity, and displacement at each station on the free surface is computed in the frequency band 0.0 to 5.0 Hz. The assumed dislocation is derived from the Kostrov (1964) displacement function for a continuously propagating stress relaxation. The azimuthal variations in the amplitudes and waveforms directly result from spatially varying slip on the fault, spatially varying radiation pattern over the fault, and the magnitude and direction of the rupture velocity. The near-source ground motions are dominated by the rupture in the direction of the receiver.

Using a 100-bar effective stress (initial stress minus sliding friction) in a Poisson solid with β = 3.0 km/sec the shear wave speed, and shear modulus μ = 3.0 × 1011 dyne/cm2, the simulated earthquake has a moment Mo = 4.5 × 1025 dyne-cm. Using a rupture velocity of 0.9β, the peak acceleration is 1195 cm/sec2 and velocity 104 cm/sec for the receiver directly on strike. For a receiver 30° off strike, the maximum acceleration 236 cm/sec2 occurs on the vertical component.
A simple method to calculate Green's functions for elastic layered media
Authors: Bouchon Michel
Published: June 2021

abstract

Green's functions for an elastic layered medium can be expressed as a double integral over frequency and horizontal wavenumber. We show that, for any time window, the wavenumber integral can be exactly represented by a discrete summation. This discretization is achieved by adding to the particular point source an infinite set of specified circular sources centered around the point source and distributed at equal radial interval. Choice of this interval is dependent on the length of time desired for the point source response and determines the discretized set of horizontal wavenumbers which contribute to the solution. Comparisons of the results obtained with those derived using the two-dimensional discretization method (Bouchon, 1979) are presented. They show the great accuracy of the two methods.
Broadband time domain modeling of earthquakes from Friuli, Italy
Authors: Cipar John
Published: June 2021

abstract

Short-period (SP) and long-period (LP) seismograms written by the main shock and two principal aftershocks of the 1976 Friuli, Italy, earthquake sequence are modeled in the time domain using synthetic seismograms. The main shock occurred on 6 May 1976 (20h 00m, Ms = 6.5) and both aftershocks on 15 September 1976 (03h 15m, Ms = 6.0 and 09h 21m, Ms = 5.9). Source models were determined initially by trial and error and then refined using a waveform inversion program. Two point sources of radiation are required to adequately model the aftershock short-period records. For the 09h 21m aftershock, the model derived from short-period records also produces good fits to the long-period data. The seismic moment of this earthquake is found to be 0.8 to 1.0 × 1025 dyne-cm. The SP model for the 03h 15m aftershock, on the other hand, predicts long-period synthetics which do not agree with the observations. In particular, the SP moment (0.37 × 1025 dyne-cm) is about 212 times smaller than the LP moment (1 × 1025 dyne-cm). Adding a long-period component to the SP model considerably improves LP waveform and moment agreement. In the case of the main shock, a reasonable fit to the observed SP data is obtained using three point sources of radiation. However, LP synthetics computed using this model do not agree with the observations, and the SP moment (0.65 × 1025 dyne-cm) is a small fraction of the LP moment (3 to 5 × 1025 dyne-cm). Time function durations indicate that the individual events inferred from the SP records are radiated from patches of the fault having radii of 2 to 4 km and stress drops in the range 35 to 276 bars. In comparison, stress drops estimated from LP data are found to be 12 bars (main shock) and 24 bars (09h 21m aftershock). These observations suggest that the short-period instruments are sensitive to the high-frequency radiation emitted from small, high-stress drop areas on the fault plane whereas the long-period instruments record the overall motion during the earthquake.
Sample Size Determination and Optimal Design of Randomized/Non-equivalent Pretest-posttest Control-group Designs
Authors: BULUS Metin
Published: June 2021

A recent systematic review of experimental studies conducted in Turkey between 2010 and 2020 reported that small sample sizes had been a significant drawback (Bulus & Koyuncu, 2021). A small chunk of the studies in the review were randomized pretest-posttest control-group designs. In contrast, the overwhelming majority of them were non-equivalent pretest-posttest control-group designs (no randomization). They had an average sample size below 70 for different domains and outcomes. Designing experimental studies with such small sample sizes implies a strong (and perhaps an erroneous) assumption about the minimum relevant effect size (MRES) of an intervention; that is, a standardized treatment effect of Cohen’s d < 0.50 is not relevant to education policy or practice. Thus, an introduction to sample size determination for randomized/non-equivalent pretest-posttest control group designs is warranted. This study describes nuts and bolts of sample size determination (or power analysis). It also derives expressions for optimal design under differential cost per treatment and control units, and implements these expressions in an Excel workbook. Finally, this study provides convenient tables to guide sample size decisions for MRES values between 0.20 ≤ Cohen’s d ≤ 0.50.
BACTERIAL TRANSLOCATION: MICROBIOTA-INTESTINE-LUNG AXIS AND PRO-INFLAMMATORY STATUS IN THE SEVERITY OF COVID-19
Authors:   Carrera de Laboratorio Clínico, Facultad de Ciencias de la Salud, Universidad Estatal del Sur de Manabí, Jipijapa, Ecuador, Valero-Cedeño Nereida , Álava Danna ,   Carrera de Laboratorio Clínico, Facultad de Ciencias de la Salud, Universidad Estatal del Sur de Manabí, Jipijapa, Ecuador, Rodríguez Ronny ,   Carrera de Laboratorio Clínico, Facultad de Ciencias de la Salud, Universidad Estatal del Sur de Manabí, Jipijapa, Ecuador, Chacín Maricarmen ,   Universidad Simón Bolívar, Facultad de Ciencias de la Salud, Barranquilla, Colombia, Cabrera-Hernández Maritza ,   Centro de Investigación de Estudios Avanzados del Maule (CIEAM), Vicerrectoría de Investigación y Postgrado, Universidad Católica del Maule, Chile, Véliz-Castro Teresa ,   Carrera de Laboratorio Clínico, Facultad de Ciencias de la Salud, Universidad Estatal del Sur de Manabí, Jipijapa, Ecuador, Carrero Yenddy ,   Carrera de Medicina, Facultad de Ciencias de la Salud, Universidad Técnica de Ambato, Ambato, Ecuador, Bermúdez Valmore ,   Universidad Simón Bolívar, Facultad de Ciencias de la Salud, Barranquilla, Colombia, Rodriguez-Morales Alfonso J. ,   Grupo de Investigación Biomedicina, Faculty of Medicine, Fundación Universitaria Autónoma de las Américas, Pereira, Colombia, Dhawan Manish ,   Department of Microbiology, Punjab Agricultural University, Ludhiana-141004, India,   The Trafford Group of Colleges, Manchester-WA14 5PQ, United Kingdom, Tiwari Ruchi ,   Department of Veterinary Microbiology and Immunology, College of Veterinary Sciences, Uttar Pradesh Pandit Deen Dayal Upadhyaya Pashu Chikitsa Vigyan Vishwavidyalaya Evam Go Anusandhan Sansthan (DUVASU), Mathura-281 001, India, Dhama Kuldeep ,   Division of Pathology, ICAR-Indian Veterinary Research Institute, Bareilly, Izatnagar, Uttar Pradesh-243122, India
Published: June 2021

Although severe acute respiratory syndrome coronavirus – 2 (SARS-CoV-2), causing coronavirus disease 2019 (COVID-19) pandemic, is primarily associated with a respiratory infection, it has also been linked to multisystem involvement that includes the digestive tract. Gastrointestinal (GI) manifestations are common in patients with COVID-19 due to the high viral load lodged in the small intestine's mucosa. As a result, it causes an increase in the permeability of the intestinal barrier that favours the passage and translocation of bacteria, from the lumen of the intestine, towards the internal environment, with the appearance of sepsis, with evidence that SARS-CoV-2 has been found in faeces. This article highlights epidemiology, clinical symptoms, and mechanisms related to manifestations of disease in the GI tract and its pathogenesis in patients with COVID-19. It highlights bacterial translocation and COVID-19, mechanisms that control bacterial translocation, intestinal infection and feco-oral transmission, defense
Sports tourism events and socio-economic well-being of the host communities: Motivations and benefits from an emerging destination
Authors: Wanyonyi Lilian , Njoroge Joseph , Juma Richard
Published: June 2021

Travel and tourism industry has been considered as a major catalyst for local community development. As an alternative way of involving the host community in tourism activities directly, sports tourism aims to enable the hosts to earn income. Host community is an important stakeholder in tourism, their wellbeing is directly proportional to sustainable tourism. Nairobi city has hosted several sports tourism events for decades, but little has been documented on how such events promote the socio-economic wellbeing of the host community. This research sought to put sports tourism events into limelight by looking at the perceived motivational factors behind hosting of sports tourism events and to assess the socio-economic benefits of hosting sports tourism events. A cross-sectional research design was used in the study with a total of 404 respondents. Questionnaires and interviews were used to collect data from informants in three stadia. Descriptive, thematic analysis and inferential statistics were used for data analysis. The major motivating factors for hosting sports tourism event were good infrastructure, expected benefits and availability of accommodation facilities. The main benefits of hosting sports tourism events were identified as employment opportunities and increased trade for local businesses. A number of recommendations were made.
Large Event Security - A Case Study of Spokane Events, WA
Authors: Senter Angela , Beattie Mark , Deng Demi
Published: June 2021

Large event security has become increasingly complex over the past 20 years. Security incidents have included headline tragedies such as the Las Vegas shooting in 2017 and the Boston Marathon bombing in 2013. Spokane, Washington, has been no exception to the need to enhance guest security for large-scale events, as evidenced by the Hoopfest gang-related shooting in 2010 and the Martin Luther King Jr. Day bombing attempt in 2011. Balancing the interests of stakeholders has become challenging for event management professionals in both planning and operations phases. Security strategies and trainings designed for security and guest service staff are critical for the success of new protocols. Transparent communication to the public is crucial for the event's success and the guarantee of guest satisfaction. This case study aims to document the leadership decisions made to enhance security for large-scale events held in Downtown Spokane and the Spokane Arena. Focusing on several tipping points, the leadership decisions and implementation are chronicled as a case study, along with the decisions and protocols that continue to influence large event security in the Spokane area. This study will benefit other event planners and venues as they face security system upgrades, protocols, and implementation.
Determination of Cholesterol and Triglyceride Concentrations in Serum Extracellular Vesicles Using Commercial Kits
Authors: Yakovlev A.A. , Antonov V.D. , Druzhkova T.A. , Guekht A.B. , Gulyaeva N.V.
Published: June 2021

Exosomes and microvesicles, collectively referred to as small extracellular vesicles (sEV) are vesicles with an average size of about 100-150 nm. Currently, the role of sEV in various aspects of signaling in the body is being actively investigated; in addition, sEV can often serve as markers of various pathologies. The active study of the sEV composition is continuing. In this study we have demonstrated that in sEV it is possible to determine cholesterol and triglycerides concentration by using commercial kits designed for serum. The technique was tested on sEV from the blood of patients diagnosed with depression and on healthy volunteers. No differences were found in the concentration of cholesterol and triglycerides in mEV from the blood serum of depressed patients and the control group. The concentration of cholesterol and triglycerides in the samples is several times higher than the sensitivity threshold of the methods set by the manufacturer of the kits.
Predictive Models for Agricultural Management
Authors:   Identification laboratory, V.A. Trapeznikov Institute of Control Sciences of Russian Academy of Sciences, Moscow, Russia, Bakhtadze Natalia N. , Maximov Evgeny M. , Maximova Natalia E. , Kozlovskaya Lamara N.
Published: June 2021

This paper is devoted to the development of predictive models for decision support systems applied in precision farming. Application of predictive models makes it possible to use resources effectively, which reduces the cost of production and increases the efficiency of agricultural production. In addition, the forecast makes it possible to reach a long-term agronomic and ecological effect due to more careful tillage and reduced use of fertilizers. The algorithms using knowledge base for creating models of grain yield are described and the results of applying these models are presented.
Tactile Scratch Electronic Block System: Expanding Opportunities for Younger Children to Learn Programming
Authors:   Sin-mook Elementary School, Republic of Korea, Jo Yunju , Chun Seok-Ju , Ryoo Jungwoo
Published: June 2021

This paper introduces our work on the development of a novel system for applying MIT’s Scratch to teaching classes of four to eight-years-old students. Scratch is a visual, block-based programming language designed for anybody to create a computer program without the worry of syntax errors by assembling icon-like command blocks. However, four to eight-year-old students have trouble using a computer mouse or keyboard and face difficulties when trying Scratch programming. This research developed a tactile, electronic block system that allows students to manipulate physical objects in a tangible way to conduct their programming tasks. The system consists of a Scratch simulator and physical, electronic blocks embodying the Scratch user interface shapes. We taught programming to the classes of second-grade elementary school students (eight-years-old) using our system. The results are encouraging. Our subjects’ interest in programming improved from 3.23 to 4.0 out of the scale of 5, and fifteen students out of twenty five were able to solve nine questions on sequence, loop, and control structure successfully, which are fundamental concepts of programming.
Effects of Students’ Home Environment, Tools, and Technology Used on Online Learning Experience in a Civil Engineering Program
Authors:   Prince Mohammad Bin Fahd University (PMU), Al Khobar, Saudi Arabia, Ayadat Tahar , Khasawneh Mohammad Ali , Chowdhury Saidur Rahman , Nayeemuddin Mohammed , Ahmed Danish , Asiz Andi
Published: June 2021

The COVID-19 pandemic has caused major disruptions in every sector of human activity around the world. The education sector is no exception. Due to physical restrictions in accessing campus infrastructures, students and instructors at academic institutions have forcibly adapted to the new norm of virtual learning with mixed expectations and outcomes. There have been several studies conducted by educational practitioners since the pandemic began, which mostly focused on how academic constituents quickly adapt to virtual learning in a general sense. The main objective of this study is to examine the effects of virtual learning infrastructure and environment on student learning, specific to the civil engineering program at Prince Mohammad Bin Fahd University (PMU). A survey was distributed to civil engineering students at PMU at the end of the fall 2020 term to gather perceptions about virtual learning and check the adequacy of online learning tools and associated environments. Student performance during virtual learning in terms of grade achievement was also investigated and compared with a normal situation. In general, it was found that students are satisfied with the current technology used to facilitate virtual learning. The anticipated outcomes of this study, including online technology readiness, curriculum adjustment, and teaching styles or methods, are to be used for virtual learning improvement should the current pandemic restriction extend to the end of the 2020–21 academic year and possibly far beyond.
The Impact of e-Learning Quality on Student Satisfaction and Continuance Usage Intentions during COVID-19
Authors:   Chulalongkorn Business School, Chulalongkorn University, Bangkok, 10330, Thailand, Puriwat Wilert , Tripopsakul Suchart
Published: June 2021

The COVID-19 pandemic has severely affected people’s lives, changing the ways of working, living, playing, and learning. With this pandemic, classroom learning has been suspended due to infection concerns, and e-learning has emerged, becoming an important mechanism for educational institutions to continue their teaching and learning activities. However, there have been only a few empirical studies providing insight into the factors affecting students’ e-learning satisfaction and usage behaviors during the COVID-19 outbreak. Thus, this study aims to investigate the impact of e-learning quality on student satisfaction and continuance usage intentions among higher education students in Thailand during the pandemic. Based on empirical research with 185 higher education students, the results revealed that e-learning quality was a second-order construct comprised of three elements, namely, course content and design, administrative and technical support, and instructor and learner characteristics. Course content and design was the most important dimension of overall e-learning quality. Furthermore, overall e-learning quality had a significant positive impact on student satisfaction and continuance usage intentions toward e-learning platforms. Mediation analysis indicated that student satisfaction partly mediated the relationship between e-learning quality and continuance usage intentions.
Research and Practice of Data Structure Curriculum Reform Based on Outcome-Based Education and Chaoxing Platform
Authors:   College of Computational Science, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China, Wu Dongqing , Guo Pengfei , Zhang Chaolong , Hou Chaojun , Wang Qian , Yang Zhiwei
Published: June 2021

In view of the problem of the data structure course being difficult to learn and teach, this paper analyses the characteristics and pain points of the course. We implement the concept of 'student-centered' education, combine outcome-based education and heuristic teaching, take students' learning effect as guidance and construct the curriculum according to the requirement of the industry. Combining students' autonomous learning, teachers' blackboard writing and on-site programming, we practice the educational concept of students as the main body and teachers as the auxiliary part. Finally, we highlight the significance and prospects of the results of this research and conclude that the research results are effective.
CS1 Student Grade Prediction: Unconscious Optimism vs Insecurity?
Authors:   REMIT, Universidade Portucalense, Porto, Portugal, Sobral Sónia Rolland
Published: June 2021

The difficulties of many students in introductory programming courses and the consequent failure and drop out make it necessary to look for motivation strategies for them to be successful. One of the strategies that is touted in the literature is self-assessment to compromise and motivate students. As we had doubts about the possibility of this strategy, we did an experiment and asked the students to predict the grades of the two tests and the two projects during a semester. Even knowing the correction grid and exercises that involve programming languages, which shows the result to the programmer, we found that the students' forecasts were not very accurate. In the first test we found that the worst students said they were going to get reasonable grades and much better than reality, while the best students thought they had worse grades than they actually had. The other moments of evaluation did not have as severe results, but forecasts continued to be inaccurate. We did tests by gender, by age, for being a freshman or not, for having taken a computer course in high school and for previous knowledge of programming languages: none of these variables proved to be as significant as the students' grades and their corresponding insecurity-fear or optimism-unconscious.
E-Services in Sudan During the Covid-19 Pandemic as a Model: a Case Study of University of Bahri-Sudan
Authors: Ibrahim Adil Hassan
Published: June 2021

The study aims to explore the barriers of online learning in Sudan. The achievement of the research purpose requires an approach which is not only describes the relations between variables, but also the experience of the stakeholders, therefore, the study adopted mixed mothed approach. To collect data, the study used two sources; secondary, and primary data sources.  The secondary sources included peer-review international journals from recognized publishers, books, newspapers and reports. The primary sources included questionnaires and interviews. 132 participants were surveyed. Two professors were interviewed. SPSS was used to analyze the data. The findings indicate that there are five unique barriers to e-learning adoption in Sudan including; poor network infrastructure, lack of bandwidth in rural areas, electricity outages, lack of electricity in rural areas, and stakeholder’s deficiency of e-skills. Furthermore, the study showed that some professors are old, and they resist the adoption of e-learning. Likewise, the study found that 67% of respondents were not able to access the internet in their areas during Covid19 lockdown, 25% of respondents do not possess computers, 35% of respondents did not receive training for gaining E-skills, and 74% of respondents prefer learning in classrooms. The study concluded that, E-learning to be adopted in Sudan, several steps can be taken such as e-skills intensive training for stakeholders, support of stakeholders, electricity and internet networks connection to whole parts of Sudan, poverty combat, and stimulation of students to accept e-learning.
Vaginal preparation with povidone iodine solution before caesarean section and its impact on the post-operative infectious morbidity
Authors: Chandra Savita , Singh Vandana
Published: June 2021

Background: A prospective randomized control trial (RCT) was conducted in the department of obstetrics and gynecology. The aim of the study was to evaluate the effect of pre-operative vaginal preparation with 1% povidone iodine solution on the post-operative caesarean infectious morbidity.Methods: 72 women were enrolled in the experimental group who received 1% povidone iodine vaginal wash and 72 in the control group who did not receive any vaginal wash. The investigators were blinded to the computer-generated random number table and to the allocation group. The clinical data was recorded and after its completion, the allocation group was revealed to the investigator. The data was tabulated and statistically analyzed using SPSS 21.Results: Age, parity, BMI, gestational age, blood loss, and operative time between the two groups was comparable. Pre-operative povidone iodine vaginal wash was more effective when membranes were intact versus ruptured. With intact membranes, statistical significance was reached for postoperative fever, seroma, endometritis, gaped incisional site, and foul discharge with p value 0.012, 0.012, 0.013, 0.027 and 0.012 respectively, between group A and B. The overall infectious morbidity in the 144 subjects showed statistical significance for endometritis, and foul-smelling lochia with p value 0.049 and 0.024 respectively; urinary tract infection, hospital stay duration, and incisional wound dehiscence were higher in group B versus group A, the difference in these parameters did not reach statistical significance.Conclusions: Pre-operative vaginal cleansing with 1% povidone iodine reduced post-operative infectious morbidity more effectively in those with intact membranes than ruptured membranes.
Psychological impact of COVID-19 on obstetrics and gynaecology residents in India
Authors: Prasad Shail , Mahato Chandrashekhar , Magon Navneet
Published: June 2021

Background: New emerging coronavirus strains are responsible for the rampant spread of COVID-19. This pandemic is not only associated with detrimental health but also with low socio-economic and adverse psychological consequences among healthcare workers, especially those working in emergency departments.Methods: Cross-sectional survey with purposive sampling was conducted. In this report, 96 obstetrics and gynaecology residents from India took part. The participants filled out a 61 item questionnaire to determine the psychological effect of COVID-19 on obstetrics and gynaecology residents in an online survey.Results: 22.9% of residents were tested RT-PCR positive to SARS-CoV2. 52.1% were reported they received an adequate quantity of personal protective equipment (PPE). 71.9% and 68.8% of residents have claimed that the number of elective cases/procedures and average OPD footfall per month respectively have decreased during this pandemic. 72.9% of residents have reported a reduction in teaching and academic activities. Of all the participants 66.7% had stress, 68.7% had anxiety while 61.5% had symptoms of depression. According to the Kessler distress scale, 37.5% of residents are likely to have a serious mental disorder. 42.7% of respondents were reported to suffer from moderate to severe clinical insomnia. The FCV-19 scale mean score was 18.79±6.782 suggesting a mild to moderate level of fear of the ongoing pandemic. Anxiety, depression, fear, psychological distress and insomnia were all strongly correlated to stress (p<0.001).Conclusions: The study highlights the urgency in dealing with the psychological wellbeing of healthcare professionals, especially in overburdened emergency services departments like obstetrics and gynaecology in such an overwhelming pandemic scenario.
Case report on peripartum cardiomyopathy in a patient with Schmidt syndrome with twin pregnancy for emergency lower segment cesarean section
Authors: Ramanathan Lakshmi , Khalilullah Shibli , Mathew Gisha V. , Zahir Lamtai , Noureddine Korichi
Published: June 2021

Peripartum and autoimmune cardiomyopathy is an uncommon rare disorder associated with pregnancy. When it occurs association with autoimmune thyroid disorder and autoimmune adrenal insufficiency, it is eponymously referred to as Schmidt syndrome or autoimmune polyendocrine syndrome type 2 (APS type 2). Peripartum cardiomyopathy (PPCM) can be difficult to diagnose as the symptoms can be masked or misinterpreted due to the normal physiological changes during pregnancy, as the symptoms of heart failure can mimic those of pregnancy. PPCM is associated with considerable morbidity and mortality and so should not be underestimated. In this report, we are discussing the management of 32-years-old female with hypothyroidism and Addison’s disease (polyglandular syndrome type 2- Schmidt syndrome) who came for emergency lower segment cesarean section (LSCS) due to twin pregnancy (abnormal doppler of the second twin) and during the period developed pulmonary edema and was diagnosed as peripartum cardiomyopathy.
Uterine artery embolization for uterine arterio-venous malformation
Authors: Sagili Haritha , Krishnan Nagarajan , Keepanasseril Anish , Priya Sathiya , Devaraj Sunilkumar
Published: June 2021

Uterine arteriovenous malformations (AVM) as a cause of abnormal uterine bleeding are listed under “not otherwise classified” in Palm-Coein classification, is an abnormal communication between an artery and vein without an intervening capillary bed resulting in increased pressure and high velocity in the venous system. We report the case of heavy menstrual bleeding in a thirty-five-year-old primiparous lady for five years with fourteen weeks sized uterus and six gm hemoglobin. Ultrasound revealed an enlarged uterus with tubular spaces and color doppler showed tubular anechoic structures, both within the myometrium, with low resistance and high-velocity pattern suggestive of uterine arteriovenous malformations. Because of nonresponse to medical management, uterine artery embolization was carried out following which she had significant reduction in menstrual bleeding emphasizing it as a differential diagnosis in all cases presenting with heavy menses. Uterine artery embolization appears to be an effective modality of treatment especially in women whose wish to preserve fertility.
Bilateral benign cystic teratoma of ovary concomitant with an occult gall bladder carcinoma in a post-menopausal woman
Authors: Mandrelle Kavita , Bhatti Sahir
Published: June 2021

Mature cystic teratomas are the most common benign germ cell tumours, and commonly seen in the reproductive age group. It rarely occurs in postmenopausal women. We report a case of bilateral dermoid cyst with cholelithiasis and occult gall bladder carcinoma in a postmenopausal woman.
Study of socio-demographic, behavioural and clinical risk factors of diabetic foot in a tertiary care centre
Authors: Sachin Idoor D. , Manasa Megaravalli R. , Subhashree P.
Published: June 2021

Background: Diabetic foot is the most devastating complication of diabetes. Diabetic foot infection is a potential limb threatening condition. Several socio-demographic, behavioural and clinical factors are responsible for higher risk of diabetic foot. Hence this study was planned with the objective to assess association between socio-demographic, behavioural and clinical risk factors and diabetic foot and response of patients to various treatment modalities.Methods: 50 patients of diabetic foot were studied over a six-month period. The diabetic foot ulcers were classified according to Wagner’s classification. Data about various socio-demographic, behavioural and clinical factors was collected. Radiological investigations, neurological examination and culture and sensitivity of ulcer discharge was done. The patients were managed by conservative or surgical management. Results: Common age group of presentation was 51-60 years. Males were more commonly affected. All participants were of low socio-economic status and majority were unskilled labourers. Tobacco (40%) and alcohol (32%) use and lack of physical activity (92%) were seen. All had diabetes of >10 years and elevated BMI. Grade 4 ulcer were the most frequent and toes were commonly involved. S. aureus was the commonest organism. Wound debridement was done in 76% patients and 34% required amputation.Conclusions: Factors like advancing age, low socio-economic status, lack of family support, occupations involving risk of trauma to foot, tobacco use, sedentary life style, and clinical factors like longer duration of diabetes, higher BMI, uncontrolled diabetes are risk factors for diabetic foot. Hence it is essential to educate the diabetic patients about these risk factors.
Management and outcomes of carcinoma stomach in Central India: a prospective cross-sectional study
Authors: Katiyar Vipin , Bansod Prasad Y. , Gupta Brajesh B.
Published: June 2021

Background: Adenocarcinoma of the stomach is one of the leading causes of cancer-related deaths worldwide. Cancer rates in India are rising with increase in life expectancy and changes in lifestyles. Although the incidence of gastric cancer has decreased, number of newly diagnosed cases of proximal gastric and esophago-gastric junction adenocarcinomas has increased markedly. It is necessary to identify the population and risk factors along with malignancy characteristics in Central India.Methods: A prospective observational study of 84 histopathological proven cases of gastric malignancy were analysed and evaluated. Treatment for the same was categorised after staging. Surgical resection, therapeutic and palliative chemotherapy was employed in the treatment protocols. A follow-up of 6 months was taken to observe the early complications.Results: Eighty-four patients were analysed and evaluated. The mean age was 54.1 year with male predominance (1.54:1). Hypertension was commonest comorbidity, while smoking was commonest associated risk factor observed. Majority (56%) of patients underwent palliative chemotherapy while 34% underwent curative surgery. Subtotal gastrectomy with Billiroth II gastrojejunostomy was commonest performed operation (34%). Postoperative wound infection was commonest complication. Mean follow-up period of 11.3 months was observed where one patient expired of ARDS and one was readmitted for anastomotic site stricture.Conclusions: There was high incidence of gastric malignancy patients presenting in stage IV in 5th decade of life with weight loss as main feature. Palliative chemotherapy is commonly followed because of advanced disease. The rates of inoperability are high and unfavourable histopathological variety occur frequently in older patients.
A study to compare the effect of topical phenytoin dressing and conventional saline dressing in chronic non-healing ulcers
Authors: V. Manoj V. , Stephen Biju
Published: June 2021

Background: Chronic non-healing ulcers; particularly diabetic and venous ulcers impose a major healthcare burden and affect quality of living. Efficacy of conventional strategies used for treatment of chronic non-healing ulcers is limited due to factors like microbial infection, necrotic tissues, tissue hypoxia, and other prevailing co-morbidities. The aim of the study was to compare efficiency of topical phenytoin-based dressings to conventional saline-based dressings for treatment of chronic non-healing wound ulcers.Methods: A prospective observational study was conducted on 60 patients who were divided in two groups. First group received conventional saline dressing-based treatment and second received topical phenytoin dressing based treatment for chronic non-healing ulcers. Efficiency of the treatment strategy was determined by statistically comparing parameters like duration of hospital stay, nature of discharge, appearance of healthy granulation tissue, and pus culture evaluation upon admission and post one and two weeks of treatment.Results: Diabetes and trauma were observed to be two major causes of chronic non-healing ulcers. No cases of venous impairment and osteomyelitis were observed in participating patients. Topical phenytoin dressing based treatment significantly reduced the duration of hospital stay and number of patients with serous discharge and aided in rapid formation of healthy granulation tissue in comparison to conventional saline based dressings. Topical phenytoin dressings also prevented microbial infection and colonization on chronic non-healing ulcers.Conclusions: Topical phenytoin-based dressing was concluded to efficiently and rapidly heal chronic ulcers while preventing microbial infection in comparison to conventional saline-based dressings.
The emerging role of laparoscopic nephrectomy in the operative management of renal trauma: is less really more?
Authors: Bokhari Akram A. , McDowall Jared , Gaibie Zakiyah , Sinha Sunil , Moeng Maeyane S. , Mutambirwa Shingai , Laher Abdullah E. , Adam Ahmed
Published: June 2021

The role of laparoscopic nephrectomy (LN) is well established in the operative armamentarium of renal surgery and has also extended to the resection of benign and malignant renal neoplasms. Despite growing evidence advocating conservative management of renal trauma, the role of LN in the management of renal trauma is not well defined. Thus, a systematic review was conducted to better define the role of LN in the subgroup of renal trauma patients requiring operative nephrectomy. In accordance with the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines, a comprehensive literature search was performed (March 2020), using the following databases: Cochrane library of systematic reviews, EMBASE, PubMed, Scopus, and web of science. Included studies were further assessed for relevance and quality using the Oxford 2010 critical appraisal skills program (CASP). A total of 620 studies were identified, non-relevant and non-English articles were excluded which resulted in 4 relevant articles being included. Due to a relative lack of data, case reports and case series were also included. The role of LN is a viable option in a select group of cases when operative intervention is already planned for advanced renal injury. The special considerations and relative contraindications to laparoscopy must be adhered to when selecting this modality in the setting of renal trauma. Future prospective studies are required to better define this relationship.
Case presentation on a rare cause of small bowel obstruction- trichobezoar: a case report
Authors: Swami Ganesh Ashok , Binorkar Ashwini Babanrao , Asawa Ganesh Radhesham , Halnikar Chandrashekhar S.
Published: June 2021

Trichobezoars are concretions of swallowed hairs retained within the digestive tract, most commonly stomach. Most common in young females and with psychiatric illness. Trichobezoar may be a cause of acute abdomen when it is complicated with acute obstruction or perforation. In this report we present a case of young girl who presented as an acute obstruction due to two large ileal trichobezoars.